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HomeMy WebLinkAbout2017-0925 PECFAWN OF VA10 PLANNING AND ENVIRONMENTAL COMMISSION September 25, 2017, 1:00 PM Vail Town Council Chambers 75 S. Frontage Road -Vail, Colorado, 81657 Call to Order Present: Pam Hopkins, Ludwig Kurz, John -Ryan Lockman, John Rediker, and Brian Stockmar, Brian Gillette Absent: Karen Perez 2. Main Agenda 3. Staff requests that the report out to the Planning and Environmental Commission be tabled to December 11, 2017 to address design considerations. A report to the Planning and Environmental Commission on the Administrator's approval of an amendment to an existing Conditional Use Permit, pursuant to Section 12-16-10, Amendment Procedures, Vail Town Code, to allow for a steel - frame tensile fabric shelter at the softball fields spectator plaza area, located at 580 South Frontage Road East (Ford Park)/U n platted, and setting forth details in regard thereto. (PEC17- 0032) Applicant: Town of Vail Planner: Jonathan Spence Motion: Table to December 11, 2017 First: Kurz Second: Stockmar Vote: 5-0-0 4. A request for a recommendation to the Vail Town Council of an application establishing Special Development District No. 42 (Vail Mountain View Residences), pursuant to Section 12-9(A), Special Development Districts, Vail Town Code, to allow for the development of a mixed use building consisting of 12 dwelling units with 15 attached accommodation units (lock -offs), 19 accommodation units and 10 employee housing units, and related uses and improvements, located at 430 and 434 South Frontage Road (Vail Mountain View Residences on Gore Creek)/ Lot 1, Vail Village Filing 5, formerly known as part of Lot 1, a Resubdivision of Tract D, Vail Village Filing 5, and setting forth details in regard thereto. (PEC17-0006) Applicant: Lunar Vail LLC, represented by Mauriello Planning Group Planner: Jonathan Spence Motion: Table to October 9, 2017 First: Stockmar Second: Kurz Vote: 6-0-0 5. A request for review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for a subdivision of a parcel of land located at 3700 North Frontage Road East/Unplatted, and setting forth details in regard thereto. (PEC17-0041) Applicant: Mauriello Planning Group Planner: Chris Neubecker Motion: Approve with Condition(s) First: Stockmar Second: Kurz Vote: 5-1-0 (Rediker opposed) Conditions of Approval: 1. Approval of this plat shall expire on December 29, 2017, unless the final plat is recorded with the Eagle County Clerk and Recorder. 2. This subdivision approval shall be contingent upon the applicant receiving approval of the pending rezoning of the property for the Housing (H) district on the western 5.4 acres of the property, and the Natural Area Preservation (NAP) district on the eastern 17.9 acres of the property. Planner Neubecker introduced the project. Neubecker spoke to the related rezoning application. Neubecker spoke to the applicable criteria for approval and the staff's recommendation. Kurz- Has the town attorney reviewed the application? Neubecker-No, but it has been reviewed by staff including the Town's Engineer Stockmar- Has anything changed related to the rezoning? Neubecker-No Rediker-What is the status of the rezoning and are they interdependent? Stockmar - Asked if the applicant would be OK with a contingency that the subdivision does not go into effect unless the Town Council approves the associated rezoning application. Mauriello indicated "yes". Mauriello, representing the applicant, provided a short PowerPoint and referenced that the criteria for approval is very similar to the rezoning. Public Comment - None Stockmar-1St step in a complex project. Supports the process. Gillette -Agrees with staff Hopkins -agrees with staff Kurz -Agrees with staff Lockman -Agrees with staff Rediker-Agrees with staff but has reservations about the applicability of the criteria at this stage in the process when the project and future development plan is unclear. Would like Town Council to address this. We should not have to make a decision without knowing what will be built here. 6. A request for a recommendation to the Vail Town Council for a Prescribed Regulations Amendment, pursuant to Section 12-3-7, Amendment, Vail Town Code, to amend Section 12-2-2, Definitions of Words and Terms, Vail Town Code, to amend and clarify the definitions of Commercial Ski Storage, Ski Club, First Floor or Street Level, and Basement or Garden Level; to create a new definition for Ski Storage Lockers; to amend Section 12-14-21 Outdoor Display of Goods concerning ski racks, and setting forth details in regard thereto. (PEC17-0042) Applicant: Town of Vail Planner: Chris Neubecker Motion: Table to October 9, 2017 First: Gillette Second: Hopkins Vote: 6-0-0 Planner Neubecker brought the commission up to speed on status of the project and some of the challenges between the regulations and guest expectations. Neubecker spoke to proposed language and questions where feedback from the PEC and the Town Council would be helpful. He spoke in general to these remaining questions. Commissioners Rediker and Gillette offered ideas on how to proceed. Neubecker discussed how we ended up where we are. Gillette asked about the genesis of the apparent problems. Rediker spoke to his understanding of the original regulations and horizontal zoning. He asked about the intersection of the definitions and operating characteristics. Neubecker used the Four Seasons operation on Wall Street to illustrate the challenges with the existing language. Stockmar spoke to a need for a clear understanding of the problem. Gillette asked for a clarification on what is occurring at the Four Seasons. Neubecker explained the different levels of the structure used by the Four Seasons. Rediker returned the discussion to the 5 questions included in the staff memorandum. Rediker spoke to the question of pedestrian easements. Neubecker spoke to the situation arising from pedestrian easements, and how many properties in the commercial core areas are surrounded by easements. Rediker spoke to his feeling that any encroachment into the easement is an impediment and that long term encroachments can be problematic. Kurz spoke to conflicting interests and overarching goals including safety, respecting business investments and aesthetics; he feels that wholesale changes are not warranted. Rediker spoke to the definitions discussion in the staff memo. A brief discussion concerning what is and is not taxed in relation to ski stores and ski storage. Hopkins asked for further clarifications regarding the Four Seasons building. Lockman asked about what other communities are doing. Neubecker spoke to other resort communities including Aspen and Breckenridge. Rediker asked about how ski shops and ski stores are related to this. Neubecker pointed to the challenges associated with the current regulations and ski store operations. Public Comment Mike Brumbaugh, Venture Sports (Base Camp) -Spoke to the Four Seasons operation, the basement situation and the easement situation. What is legal and what is not illegal? Rediker asked how the current regulations impact his operation. Mike Brumbaugh spoke to what their operation is and the gray areas. Tom Higgins, American Ski Exchange - Very difficult. Everyone has self -interests on the task force. Want more bars and not more private clubs. Need to be concerned with vitality. This issue is getting more complicated, not less. We have a short season. Is ski storage a service or an amenity? Changing the rules penalizes those that have played by the rules. Rediker asked Tom Higgins to describe his operation. Tom Higgins described his business operation. Marco Valenti, Vail Resorts Retail - Spoke to the evolution of the discussions within the task force. Spoke to mobile ski storage as opposed to ski clubs. Felt that certain retail aspects are outside the purview of the task force. Spoke to guest expectations. Rediker asked which ski clubs Vail Resorts operates Marco Valenti spoke to the clubs and their operations. Supports adding clarity. Concerned about easements and its affects on business operations. Zach Meyers, General Manager of the Arrabelle, spoke to the Arrabelle operation and how it was designed with the regulations in mind. Sean Filiault, Pepi's Sports - Spoke about his operation. Was not a part of the task force (out of town). Does not support wheeling lots of racks out onto the street. Brent Martin, Four Seasons - Discussed the model that they run. Reminded the task force and the PEC that they are not competing with each other, but with other destination resorts (i.e. Jackson Hole). Spoke to the need for a location closer to the hill which was what started the partnership with the Gorsuch. He described what occurs on what level of the "Hong Kong" building on Wall Street. Does not see why ski clubs on the second floor are a problem; they drive more traffic than office. Spoke to the ski rack issue. Jeff Evans, Christie Sports - Spoke to the changes in the economics of the ski industry. Greatest growth will be with rentals. Rediker asked about storage of skis. Evans spoke about the 60 racks that store the rental skis. Neubecker spoke to pedestrian easements in the vicinity of Christie Sports. Tommy Neyens, Ski Valet in Lionshead - Greatest concern is equity. Would like to keep things the way they are. No ski clubs on the second floor. Has concerns about ski storage on the first floor. Supports horizontal zoning. Outdoor storage on private property is OK. Hours may be too generous. Commissioner Lockman- Still confused. Clarity? Operations all over the place. What has been proposed will not necessarily help. Does not see the answers. Can some 7 91 of these issues be handled on a case by case basis? Commissioner Hopkins- Understands the complexity of the issue. Sees it as old school vs. new services. Understands the concerns with black holes (spaces that are not used in summer) and ski clubs. Not ready to take action. Commissioner Kurz- Not ready to act. Recognizes lack of agreement and feels that pressure to act may result in more unintended consequences. Commissioner Gillette- More than one issue. Bulk ski storage vs. skis for sale. How many ski racks to we want to see? Bulk Ski Storage may be different than ski clubs. Commissioner Stockmar- Understands the problem better, but not fully. Issues about commercial vibrancy are present. Concern with just being a storage area. Have not reached an answer. It's more than about ski storage. This is the tip of the iceberg concerning vitality. Commissioner Rediker-Appreciated the public's input. Horizontal zoning still valid and important. What is ski storage? Maybe looking at what a rental shop does. Impractical for ski rental shops to store skis in the basement. Don't want rental shops to be fronts for hotels. Concerned with 2nd floor ski clubs. Spoke to pedestrian easements. Not sure what the answer is. Case by case analysis of easements may be necessary. Approval of Minutes September 11, 2017 PEC Meeting Results Motion: Approve First: Kurz Second: Stockmar Vote: 5-0-1 (Gillette Abstained) Adjournment The applications and information about the proposals are available for public inspection during regular office hours at the Town of Vail Community Development Department, 75 South Frontage Road. The public is invited to attend the project orientation and the site visits that precede the public hearing in the Town of Vail Community Development Department. Times and order of items are approximate, subject to change, and cannot be relied upon to determine at what time the Planning and Environmental Commission will consider an item. Please call (970) 479-2138 for additional information. Please call 711 for sign language interpretation 48 hour prior to meeting time. Community Development Department TOWN OF VA10 VAI L TOWN PLANNING AND ENVIRONMENTAL AGENDA MEMO MEETING DATE: September 25, 2017 ITEM/TOPIC: A request for review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for the platting and subdivision of a parcel of land in the South 1/2, Southeast 1/4, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East, and setting forth details in regard thereto. (PEC17-0041) ATTACHMENTS: File Name Description PEC17- PEC17-0041 East Vail Subdivision - Staff 0041_Staff Memo East Vail_Employee_Housing_Subdivision.pdf Memo A_Vicinity_Map_-_Vail_Resorts East Vail_Housing.pdf B_Legal_Description_of_Vail_Resorts Rezoning.pdf C_Applicant_Narrative_Vail_Resorts East Vail_Subdivision.pdf D_East Vail_Workforce_Housing_Subdivision_Plat.pdf E Attachment E_Rockfall_Hazard_Study_Part1.pdf E Attachment E_Rockfall_Hazard_Study_Part2.pdf E Attachment E_Rockfall_Hazard_Study_Part3.pdf F_Attachment F_W ildlife Assessment.pdf PEC17-0041 East Vail Subdivision - Attachment A - Vicinity Map PEC17-0041 East Vail Subdivision - Attachment B - Legal Description PEC17-0041 East Vail Subdivision - Attachment C - Applicant Narrative PEC17-0041 East Vail Subdivision - Attachment D - Final Plat PEC17-0041 East Vail Subdivision - Attachment E - Rock -fall Hazard Study Part 1 of 3 PEC17-0041 East Vail Subdivision - Attachment E - Rock -fall Hazard Study Part 2 of 3 PEC17-0041 East Vail Subdivision - Attachment E - Rock -fall Hazard Study Part 3 of 3 PEC17-0041 East Vail Subdivision - Attachment F - Wildlife Assessment rowN of vain Memorandum TO: Planning and Environmental Commission FROM: Community Development Department DATE: September 25, 2017 SUBJECT: A request for review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for the platting and subdivision of a parcel of land in the South 1/2, Southeast 114, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East, and setting forth details in regard thereto. (PEC17-0041) (Please see Attachment 8 for the full legal description of the property.) Applicant: The Vail Corporation (aka Vail Resorts), represented by Mauriello Planning Group Planner: Chris Neubecker SUMMARY The applicant, the Vail Corporation (aka Vail Resorts), represented by Mauriello Planning Group, is requesting the review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for platting and subdivision of an unplatted parcel of land in the South 1/2, Southeast 114, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East. The purpose of this application to subdivide the parcel of land in order to create a legal description, and to delineate the boundary between two new zone districts that are being reviewed under a separate Zone District Boundary Amendment application. (Pease see Attachment 8 for a full legal description). Based upon Staff's review of the criteria outlined in Section VII of this memorandum and the evidence and testimony presented, the Community Development Department recommends approval of this application, subject to the findings noted in Section VIII of this memorandum. A vicinity map (Attachment A), the legal description of the current property (Attachment B), Applicant's narrative (Attachment C), and proposed plat (Attachment D) are attached for review. II. DESCRIPTION OF REQUEST The applicant, the Vail Corporation (aka Vail Resorts), represented by Mauriello Planning Group, is requesting the review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for platting and subdivision of an unplatted parcel of land in the South 1/2, Southeast 114, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East. The purpose of the application is to subdivide the vacant, undeveloped, unplatted property to create two lots, one of which will be used for future development of employee housing units (EHUs), and the other lot which will remain undeveloped. The proposed property line between the two new lots will also become the boundary for a proposed rezoning of the property, which is currently under review through a separate rezoning application, PEC17-0039. Please see the proposed Final Plat, Attachment D. The graphic below shows the location of the new lots with this subdivision. (See Attachment D for a detailed Final Plat). Aupust17.2017 III. BACKGROUND On November 5, 1974 the subject property was annexed into the Town of Vail, via Ordinance No. 20, Series of 1974. This annexation included most of east Vail, and the Katsos Ranch area. The property has not been developed, and remains void of any buildings. The western portion of the lot contains evidence of an old road cut through the property. This old road area is void of trees in a straight line, about 8-10 feet wide. There is no pavement in this area, and it is unclear when or why the road may have been originally built. However, there are utility manholes for electric power along this old road. On September 11, 2017, the Planning and Environmental Commission reviewed an application for a rezoning of this property. The current zoning on the property is Two Family Residential (R) District. The application was to rezone the western 5.4 acres of the property to Housing (H) District, and rezone the eastern portion of the property to Natural Area Preservation (NAP) District. The PEC voted 6-0 to recommend approval to the Vail Town Council for this rezoning application. On September 19, 2017, the Vail Town Council held the first reading of Ordinance No. 13, Series of 2017, to rezone this property. The Town Council voted 5-2 to approve the first reading of the ordinance. IV. APPLICABLE PLANNING DOCUMENTS Staff believes that following provisions of the Vail Town Code are applicable to this request: TITLE 12: ZONING REGULATIONS, VAIL TOWN CODE CHAPTER 12-2-2: DEFINITIONS OF WORDS AND TERMS (in part) TITLE 13: SUBDIVISION REGULATIONS, VAIL TOWN CODE (in part) Chapter 4, Minor Subdivision, Title 13, Subdivision Regulations, of the Vail Town Code prescribe the review criteria for a request for a minor subdivision. Pursuant to Section 13-4-2, Procedure, Vail Town Code, the criteria for reviewing the final plat shall be as contained in Section 13-3-4, Commission Review of Application; Criteria and Necessary Findings, Subdivision Regulations, Vail Town Code. According to Section 13-4-2C, Review and Action on Plat, "The Planning and Environmental Commission shall review the plat and associated materials and shall approve, approve with modifications or 1IF/ disapprove the plat within twenty one (2 1) days of the first public hearing on the minor subdivision or the minor subdivision will be deemed approved. A longer time period for rendering a decision may be granted subject to mutual agreement between the Planning and Environmental Commission and subdivider". According to Section 13-3-4, Commission Review of Application; Criteria and Necessary Findings, Subdivision Regulations, Vail Town Code, (in part) "The burden of proof shall rest with the applicant to show that the application is in compliance with the intent and purposes of this chapter, the zoning ordinance and other pertinent regulations that the planning and environmental commission deems applicable. Due consideration shall be given to the recommendations made by public agencies, utility companies and other agencies consulted under subsection 13-3-3C of this chapter. " SITE ANALYSIS Address: Legal Description: description) Zoning: Land Use Plan Designation Current Land Use: Geological Hazards: 3700 N. Frontage Road East Unplatted (See Attachment 8 for legal Two -Family Residential (R) District Open Space Undeveloped High Severity Rockfall Standard Allowed / Required in Housing (H) District Existing (tinplated Parcel) Proposed Site Area Determined by PEC 1,015,470 sq. ft. 235,093 sq. ft. Setbacks Front — 20' Side — 20' Rear — 20' Undeveloped No change Height Determined by PEC None No change Density Determined by PEC None No change GRFA Determined by PEC None No change Site Coverage Max. 55% of site area None No change Parking/Loading Per Title 12, Chapter 10 None No change Landscaping Min. 30% of site area 100% No change Standard Allowed / Required in Natural Area Preservation (NAP) District Existing (Unplatted Parcel) Proposed Site Area No minimum 1,015,470 sq. ft. 780,377 sq. ft. Setbacks N/A N/A No change Height N/A N/A No change Density N/A N/A No change GRFA N/A N/A No change Site Coverage N/A N/A No change Parking/Loading Determined by PEC No change No change Landscaping N/A N/A No change VI. SURROUNDING LAND USES AND ZONING Existing Use Zoning District North: U.S. Forest Service None South: 1-70 Interchange / Multifamily None / Residential Cluster Residential East: U.S. Forest Service None West: Vail Memorial Park Natural Area Preservation VII. REVIEW CRITERIA The following are the review criteria for a minor subdivision, as outlined in Section 13-3-4, Vail Town Code: 1. The extent to which the proposed subdivision is consistent with all the applicable elements of the adopted goals, objectives and policies outlined in the Vail comprehensive plan and is compatible with the development objectives of the town; and Staff finds the proposed subdivision is consistent with all applicable elements of the adopted goals, objectives and policies outlined in the Vail Comprehensive Plan and is compatible with the development objectives of the Town. Specifically, the subdivision will help to ensure a site for future employee housing development, which is a goal identified in the Vail Housing 2027 Plan, and the Vail 20/20 Strategic Action Plan. This subdivision will also facilitate the creation of a large tract for nature preserves. Some of the goals that this subdivision will help to advance include: Vail 20/20 Focus on the Future — Strategic Action Plan (in part) LAND USE Goal #2: Land use and development decisions will address environmental sustainability as a priority of the community. • Work with public and non-profit partners to ensure that environmental issues within the town and region are being addressed. • Educate developers and applicants on how to incorporate environmental sustainability into projects. Goal #4: Provide for enough deed -restricted housing for at least 30 percent of the workforce through policies, regulations and publicly initiated development. • Address the zoning regulations to provide more incentives for developers to build employee housing units. ENVIRONMENTAL SUSTAINABILITY Goal #2: Energy Management in Buildings and Transportation: Reduce the town's 2007 baseline green house gas emissions. • Support employee housing initiatives in order to reduce trips into Vail. Goal #3: Ecosystem: Improve the health and diversity of the forest and mountain ecosystem while recognizing the interdependence of the wildland urban interface (WUI) corridor within Vail. • Work with non-profit organizations and the Colorado Department of Wildlife to improve wildlife conditions. HOUSING Goal: The Town of Vail recognizes the need for housing as infrastructure that promotes community, reduces transit needs and keeps more employees living in the town, and will provide for enough deed -restricted housing for at least 30 percent of the workforce through policies, regulations and publicly initiated development. • Conduct inventory of all sites with development potential and pursue opportunities for acquiring undeveloped or underdeveloped properties. • Update the Vail Land Use Plan and identify more areas for employee housing. ECONOMY Goal #3: Maintain a town -wide workforce in which at least 30 percent of people who work in Vail also live in Vail. • Support the local economy by working with the business community to address future workforce housing needs as they relate to business in Vail. The Land Use Plan recommends this site for open space. Staff believes that this designation was an error, and that open space use was recommended at a time when this property was believed to be owned by the Colorado Department of Transportation (CDOT), and was not known to be owned privately or have development rights. The property is currently zoned Two -Family Residential (R), and the zoning will be used to determine any allowed land use or development for the property. 2. The extent to which the proposed subdivision complies with all of the standards of this title, as well as, but not limited to, title 12, "Zoning Regulations", of this code, and other pertinent regulations that the planning and environmental commission deems applicable; Staff finds the proposed subdivision is in compliance with all standards of Title 13, Subdivision Regulations, and Title 12, Zoning Regulations, Vail Town Code. The resulting new Lot 1 meets the existing development standards for the anticipated zoning of Housing (H) District, which does not have a minimum lot area or minimum lot dimensions. The new Tract A for Natural Area Preservation (NAP) also meets the required subdivision standards, and other relevant standards for this zoning district. There are no minimum lot area or lot dimensions required for the Natural Area Preservation (NAP) district. 3. The extent to which the proposed subdivision presents a harmonious, convenient, workable relationship among land uses consistent with municipal development objectives; Staff finds the proposed subdivision presents a harmonious, convenient, workable relationship among land uses that is consistent with municipal development objectives. The subdivision will allow for a future development of employee housing, a future nature preserve, and will also facilitate the legal descriptions for the proposed rezoning of this land. These uses are compatible with the adjacent residential uses, and with U.S. Forest Service property. 4. The extent of the effects on the future development of the surrounding area; Staff finds the proposed subdivision will have no negative impacts on the future development of the surrounding area. At this time, there is no specific development plan for this property, and no current plans to install roads or utilities. As a result, this subdivision will have no direct impact on the future development of the surrounding area. Effects on the future development of the surrounding area will be reviewed with future subdivisions, and also with any future development plan for the construction of employee housing units. 5. The extent to which the proposed subdivision is located and designed to avoid creating spatial patterns that cause inefficiencies in the delivery of public services, or require duplication or premature extension of public facilities, or result in a "leapfrog" pattern of development; This property is already served by local roads and utilities, and other necessary infrastructure to serve future development on Lot 1. There is no need to extend utilities to the property. The property is also served by existing transit and the bus stop for the Town of Vail free bus system is directly in front of this property. The property is located near other residential development, including the adjacent property to the southeast, Pitkin Creek Townhomes. The property is within the current boundary of the Town of Vail. Staff finds the proposed subdivision will not cause any inefficiency in the delivery of public services and will not require duplication or premature extension of public services, and will not result in a leapfrog pattern of development. 6. The extent to which the utility lines are sized to serve the planned ultimate population of the service area to avoid future land disruption to upgrade undersized lines; Staff finds the utility lines are sized to serve a complete build -out of the site, which does not change with the subdivision of the property. It is not known at this time what the planned ultimate population of the service area will be, as no development plan has been created or submitted for review. The Eagle River Water and Sanitation District (ERWSD) has indicated that the applicant will be required to dedicate water rights or pay a cash -in -lieu of water rights, if accepted by the ERWSD board, as a condition of their providing servicer. ERWSD has also indicated that they may need to create a loop in the water lines in this area through any future development to connect to the water line near Pitkin Creek Townhomes, in order to improve hydraulics (water flow) in this area. The determination of the size and location of water and sewer lines can not be determined until a site specific development plan is created for this property. 7. The extent to which the proposed subdivision provides for the growth of an orderly viable community and serves the best interests of the community as a whole; Staff finds that the proposed subdivision provides for the growth of an orderly viable community and serves the best interests of the community as a whole since the subdivision allows for the proposed Lot 1 to be developed for deed restricted employee housing, and for Tract A to provide a site or nature preserves. The proposed subdivision will help to advance the goals in the Vail Town Council Action Plan, 2015-2017: "Grow a vibrant, diverse economy and community and preserve our surrounding natural environment, providing our citizens and guests with exceptional services and an abundance of premier recreational, cultural and educational opportunities. " 8. The extent to which the proposed subdivision results in adverse or beneficial impacts on the natural environment, including, but not limited to, water quality, air quality, noise, vegetation, riparian corridors, hillsides and other desirable natural features; Staff finds the proposed subdivision will not result in any adverse impacts on the natural environment, including, water quality, air quality, noise, vegetation, riparian corridors, hillsides and other desirable natural features. The property is within the existing Town of Vail boundary, and is not sprawl. The subdivision will facilitate the future development of employee housing clustered on a small portion of the property, while preserving a large portion of the property for natural areas and preservation of vegetation and wildlife habitat. This property is within a mapped rockfall hazard area. Development on steep slopes and in hazard areas is discouraged, but not prohibited in all areas. Development in rockfall areas is allowed, with proper mitigation. The future developer of this property will be required to mitigate the rockfall hazards as part of any future development of employee housing on Lot 1. The geological investigation provided by the applicant's professional geologist recommends the construction of a rockfall barrier at least 12 feet in height. The final design of the barrier will require further study, and will be required as part of the development plan for Lot 1. The development plan is required to be reviewed by the Planning and Environmental Commission at a public hearing. At the time of an application for a development plan, an environmental impact report will also be required. VIII. STAFF RECOMMENDATION The Community Development Department recommends approval with conditions of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for the platting and subdivision of a parcel of land in the South 1/2, Southeast 114, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East, and setting forth details in regard thereto. (PEC17-0041). This recommendation is based upon the review of the criteria outlined in Section VII of this memorandum and the evidence and testimony presented. Should the Planning and Environmental Commission choose to approve this request, the Community Development Department recommends the Commission pass the following motion: "The Planning and Environmental Commission approves the applicants' request for a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for the platting and subdivision of a parcel of land in the South %, Southeast %, of Section 2, Township 5, Range 80 West 6th Principal Meridian, located at 3700 N. Frontage Road East, and setting forth details in regard thereto. (PEC 17-0041). " Should the Planning and Environmental Commission choose to approve this minor subdivision, the Community Development Department recommends the Commission makes the following findings: 'Based upon a review of Section Vll of the September 25, 2017 staff memorandum to the Planning and Environmental Commission, and the evidence and testimony presented, the Planning and Environmental Commission finds.- 1. inds: 1. That the subdivision is in compliance with the criteria listed in Section 13-4 Minor Subdivision Vail Town Code; and 2. That the subdivision is consistent with the adopted goals, objectives and policies outlined in the Vail comprehensive plan and compatible with the development objectives of the town; and 3. That the subdivision is compatible with and suitable to adjacent uses and appropriate for the surrounding areas,- and reas;and 4. That the subdivision promotes the health, safety, morals, and general welfare of the town and promotes the coordinated and harmonious development of the town in a manner that conserves and enhances its natural environment and its established character as a resort and residential community of the highest quality. " The Community Development Department requests that the PEC add the following condition of approval: 1. Approval of this plat shall expire on December 29, 2017, unless the final plat is recorded with the Eagle County Clerk and Recorder. IX. ATTACHMENTS A. Vicinity Map B. Legal Description C. Applicant Narrative, August 28, 2017 D. Final Plat — East Vail Workforce Housing Subdivision, August 28, 2017 E. Rockfall Hazard Study, June 19, 2017 F. Wildlife Assessment, August 10, 2017 �k.,V/ ATTACHMENT B - LEGAL DESCRIPTION Legal Description of Vail Resorts Rezoning 3700 N. Frontage Road East Vail, Colorado 81657 A PART OF TRACT II OF BOOK 166, PAGE 61 NOW BEING ALL THAT PART OF THE SOUTH 1/2 SOUTHEAST 1/4 OF SECTION 2, TOWNSHIP 5 SOUTH, RANGE 80 WEST, 6TH P.M. LYING NORTH OF 1-70 AND PITKIN CREEK TOWNHOUSES RECEPTION NO. 190521. BEING MORE PARTICULARLY DESCRIBED AS FOLLOWS: COMMENCING AT THE SOUTHEAST CORNER OF SAID SECTION 2, FROM WHENCE THE EAST 1/16 OF SECTION 2 AND SECTION 11 BEARS N89041'53"W, 1325.07' SAID LINE FORMING THE BASIS OF BEARINGS FOR THIS DESCRIPTION. THENCE N01 °51'14"E ALONG THE EAST LINE OF SAID SOUTH 1/2 OF THE SOUTHEAST 1/4 OF SECTION 2 A DISTANCE OF 398.97' TO THE TRUE POINT OF BEGINNING; THENCE ALONG THE NORTHERLY LINE OF SAID PITKIN CREEK TOWN HOUSES THE FOLLOWING TWO (2) COURSES; 1) N 60000'00" W A DISTANCE OF 420.00'; 2) N 90000'00" W A DISTANCE OF 339.75'; THENCE ALONG THE NORTHERLY RIGHT OF WAY OF SAID INTERSTATE HIGHWAY 70 THE FOLLOWING FIVE (5) COURSES; 1) N 02032'29" W A DISTANCE OF 2.90'; 2) N 59059'34" W A DISTANCE OF 478.70'; 3) N 65042'12" W A DISTANCE OF 301.50'; 4) N 72013'06" W A DISTANCE OF 613.90'; 5) N 55043'36" W A DISTANCE OF 297.66' TO A POINT INTERSECTING THE NORTH LINE OF S1/2 SOUTHEAST 1/4 OF SECTION 2; THENCE S 88009'34" E ALONG SAID NORTH LINE OF THE SOUTH 1/2 OF THE SOUTHEAST 1/4 OF SECTION 2 A DISTANCE OF 2253.37' TO A B.L.M. MONUMENT FOUND IN PLACE AT THE SOUTH 1/16 CORNER OF SECTIONS 1 AND 2; THENCE S 01°56'08" E ALONG THE EAST LINE OF SAID SOUTH 1/2 OF THE SOUTHEAST 1/4 OF SECTION 2 A DISTANCE OF 637.05' TO A B.L.M. MONUMENT FOUND IN PLACE AT THE ANGLE POINT OF SECTIONS 1 AND 2; THENCE S 01 051'14" W CONTINUING ALONG SAID EAST LINE OF SAID SOUTH 1/2 OF THE SOUTHEAST 1/4 OF SECTION 2 A DISTANCE OF 222.52' TO THE TRUE POINT OF BEGINNING. BEING 23.3 ACRES MORE OR LESS. ATTACHMENT C - APPLICANT NARRATIVE East Vail Workforce Housing Parcel Minor Subdivision IVUI Mauriello Planning Group Submitted to the Town of Vail: August 28, 2017 VAILRESORTS' EXPERiENCL OF a LIFETIME Introduction Vail Resorts, represented by Mauriello Planning Group, is requesting a minor subdivision for the property located just to the north of the East Vail 1-70 interchange. The existing zoning of the property is Two -Family Residential (R) zone district. The property is proposed to be zoned Housing Zone District (H) on the western 5.4 acres of the site, and Natural Area Preservation District (NAP) on the eastern 17.9 acres of the site. The proposed subdivision is proposed for the sole purposes of providing a legal description to unplatted property and to facilitate the zone district boundaries to follow platted lot lines. No development plans for any workforce housing project have been developed at this time. Once the boundaries of the parcels are approved and the zoning is established, any development plan submitted to the Town will need to stand on its own and comply with the Town's regulations, including the submittal of an environmental impact report. A geohazard report, completed by Cesare, Inc., and a wildlife report, completed by Rick Thompson of Western Ecosystems, Inc., have been included with this submittal. Photo of a portion of the property 2of13 Site Analysis Property: Unplatted Parcel. Located just to the north of the East Vail interchange Lot Area: 23.3 acres Zoning: Two -Family Residential Proposed Zoning: Housing Zone District (5.4 acres) / Natural Area Preservation District (17.9 acres) Hazards: High Severity Rockfall, Some Slopes in Excess of 40% As indicated in the Rockfall Hazard Study that was completed by Cesare, Inc., the report recommends rockfall remediation, stating: Based on the CRSP [Colorado Rockfall Simulation Program] analysis results and existing rockfall mitigation structures on the neighboring site to the west, a rockfall barrier or wall at last 12 feet in height is recommended. Based on site conditions, including such aspects as slope angle and property boundaries, a rigid wall system would be more ideal than a flexible fence or berm/basin. In reviewing any landslide considerations for the property, the report states: Based on the lack of evidence of recent landslide movement... Cesare does not recommend monitoring of the landslide at this time. Slope stability should be a primary consideration if ground modifications and development are planned in or near the landslide mass. The geohazard report also recommends that debris flow hazard potential be considered in future development stages. Rockfall Map :f;+:*y �* f - *�': �i � �''t a��`i�a�+Y� LC ..f.,`rs: x'.J'_:: 'x .�. .r •y-•~,r�J �' ��•_ �• �' a j ray T i{,:.. j" "t' yr• 41 ..a•` y }w KSlopes >40% i. �'� Slopes 30%-40% 41. Criteria for Review: Minor Subdivision Section 13-3-4: COMMISSION REVIEW OF APPLICATION; CRITERIA AND NECESSARY FINDINGS, of the Vail Town Code provides the criteria for review of a minor subdivision. The following section includes the criteria, along with an analysis of the compliance of the proposal with the criteria: (1) The extent to which the proposed subdivision is consistent with all the applicable elements of the adopted goals, objectives and policies outlined in the Vail comprehensive plan and is compatible with the development objectives of the town; and Applicant Analysis: The property is governed by the Vail Land Use Plan. In addition, there is specific discussion of this property in the Comprehensive Open Lands Plan. Other applicable plans include the Vail 20/20 Plan and the Housing Strategic Plan, all of which are described below: • Vail Land Use Plan The adopted map of the Vail Land Use Plan shows a designation of "Open Space" for the property. The Open Space designation is defined as follows: 0 LAND USE DESIGNATIONS HillsiCP. Rp,,&nrlal 1 ra-isitim Area Low Density Rusioentiai Publiosemi-Pub is MR.dihim 11 -unity I ZP.RIdPntial Sk Ease - Hi-gh Density Res dei&il Park Rescrl Acconmadaticns and Services Open Space C Urrri nun i ty orr L; e Not De sionated Villagc rdnstcr Plan yI Ski Petal LionsHead Redeueiopment Ieas:er Plan Gore Creek �CommunityCDmnercialf Town Eoundary Passive recreation areas such as greenbelts, stream corridors and drainage ways are the types of areas in this category. Hillsides which were classified as undevelopable due to high hazards and slopes over 40% are also included in this area. These hillside areas would still be allowed types of development permitted by existing zoning, such as one unit per 35 acres, for areas in agricultural zoning. Also, permitted in this area would be institutional /public uses. 5of13 This property was likely included in this category due to the confusion regarding ownership, in addition to steep slopes and high rockfall hazard. At the time of the adoption of the Vail Land Use Plan the zoning and private ownership status of the property was not clear and there was no detailed analysis performed to determine the slopes on the property. The applicant believes the designation to be erroneous and the result of incomplete or inaccurate information. The subdivision proposal implements the zoning of Housing Zone District on the more buildable portion of the property (slopes less than 40%), while the remainder of the site which is generally slopes in excess of 40% will be zoned Natural Area Preservation, which precludes development. This would be in keeping with the intent of the land use designation, while providing a developable site for employee housing under the Housing Zone District in an area that is currently impacted by the presence of 1-70 and the North Frontage Road. • Comprehensive Open Lands Plan At the time of adoption of the Comprehensive Open Lands Plan, the applicant believes this property was thought to be owned by CDOT. It is identified as Parcel 36. The plan indicates that the existing zoning of the property is Two - Family Residential, and its open space objective is "environmental protection" with a proposed use of "open space" and as a "high" priority. The map designation is shown below: With the steeper portions of the site proposed to be zoned NAP, and only the flatter, more developable areas proposed to be zoned H, the intent of the Comprehensive Open Lands Plan is met, while simultaneously helping to meet the Town's goals of providing more employee housing within the Town boundaries. Clearly had the property been known to be in private ownership, the recommendations of this plan would have been different to avoid the taking of private development rights. • Vail 20/20 Plan The Vail 20/20 Plan provides the following goals: Parml 35- Parcels C: -Z CI -3. 6-4 and G-5 Lpw priority LOA parcels: T(YSi "Art, from U.S, Forest Scrvicc. Thcn TOV should trade these parcels to C:L7C)Tfof parcel 36 [which iS now owned by Caan. 'T= e 13 & X111 VJ at ,Land Nortlt of Fast Vail InWOO&ee Filth priority; Tt]V acquire development rights for open spere use or trade parcels) 35 for parcel 36. Has potential for dcfvelopment. Provide for enough deed -restricted housing for at least 30 percent of the workforce through policies, regulations and publicly initiated development. The Town of Vail recognizes the need for housing as infrastructure that promotes community, reduces transit needs and keeps more employees living in the town, and will provide for 6of13 enough deed -restricted housing for at least 30 percent of the workforce through policies, regulations and publicly initiated development. The proposed zoning of Housing on the buildable area of the site helps to further the goal of the Town of Vail to provide deed -restricted housing for 30% of the workforce. This property creates an exciting opportunity to create new workforce housing stock, while still protecting the steeper hillside from development by zoning the steep portions NAP. • Employee Housing Strategic Plan The Employee Housing Strategic Plan outlines the Town of Vail's goals and policies to ensure employee housing. It provides the following objectives: •;• Actively address affordable housing for Vail workers to ensure that the community remains competitive in economic terms. •;• Increase and maintain deed -restricted housing within the Town to encourage the efficient use of resources by placing employees closer to their place of work. The proposed subdivision and zoning will allow for the creation of new deed -restricted employee housing units within the Town of Vail, allowing the Town of Vail to remain economically competitive in attracting and maintaining a quality workforce. The subdivision proposal is consistent with the goals and objectives of the various Town of Vail planning documents and helps to further one of Vail's critical needs: creating employee housing within the Town of Vail boundaries to ensure that Vail remains economically competitive while simultaneously preserving the majority of the site as open space, another identified goal of the Town of Vail. That these two objectives can be met on privately -owned property within the Town of Vail boundaries furthers the goals and objectives of the various Town of Vail planning documents. (2) The extent to which the proposed subdivision complies with all of the standards of this title, as well as, but not limited to, title 12, "Zoning Regulations", of this code, and other pertinent regulations that the planning and environmental commission deems applicable; and Applicant Analysis: The proposed subdivision is to facilitate the zoning of the property from Two -Family Residential to Housing on the western portion of the property (Lot 1) and Natural Area Preservation on the eastern portion of the property (Tract A). The map below indicates the proposed zoning which has been submitted under a separate application. Section 12-61-1 provides the purpose of the H zone district: 7of13 The housing district is intended to provide adequate sites for employee housing which, because of the nature and characteristics of employee housing, cannot be adequately regulated by the development standards prescribed for other residential zone districts. It is necessary in this zone district to provide development standards specifically prescribed for each development proposal or project to achieve the purposes prescribed in section 12-1-2 of this title and to provide for the public welfare. Certain nonresidential uses are allowed as conditional uses, which are intended to be incidental and secondary to the residential uses of the district. The housing district is intended to ensure that employee housing permitted in the zone district is appropriately located and designed to meet the needs of residents of Vail, to harmonize with surrounding uses, and to ensure adequate light, air, open spaces, and other amenities appropriate to the allowed types of uses. Proposed Zoning r Fwnu S.sC P 1 IE 3, 5' x568' VWE 18.16' I S Fl Cl T C[RNf,F Zr.pRa��RT T � aROR[Rr= rOEA CF TOK Fn Pwn .325' FI Y AI IM IMIU CA' The H zone district allows the Planning and Environmental Commission (PEC) to set most development standards, creating flexibility to create a housing project that is suitable to the individual site. As a result, the proposed subdivision facilitating the zone district amendment is consistent with the H zone district. There is no preconceived notion about densities, building layouts, or building height associated with the proposed subdivision and zoning of the property. The PEC will evaluate any development proposal, its impacts, and apply the review criteria in determining the final outcome. Section 12-8C-1 provides the purpose of the NAP zone district: 8of13 N-4 I IN! 51j2 SCI j/ SE2'ION 2 1711N05_N LUI 1 P NSING- IRC w H OU1151NG ;F C71 5TP.ILT I ^+ iRnCT A A'a 1Y; 17.d ACRES +I- PRpPnSFn /rp Nn NARFML MEA PRESERVATION IN N S� V5- FORE5T 5=R4CE —FOUND 175 A1111i CAP 3W +091_AP NO2'32'2rW_ N8C'CD' M-ia • FFC TON HOOFS !p 'n a #I NCL 190621' . • [9r 1N' BR95 OF EEJVRIRG6 eUn --- u n_MlruWL LN' FIN 3.25" ALUANVM CRP The H zone district allows the Planning and Environmental Commission (PEC) to set most development standards, creating flexibility to create a housing project that is suitable to the individual site. As a result, the proposed subdivision facilitating the zone district amendment is consistent with the H zone district. There is no preconceived notion about densities, building layouts, or building height associated with the proposed subdivision and zoning of the property. The PEC will evaluate any development proposal, its impacts, and apply the review criteria in determining the final outcome. Section 12-8C-1 provides the purpose of the NAP zone district: 8of13 The natural area preservation district is designed to provide areas which, because of their environmentally sensitive nature or natural beauty, shall be protected from encroachment by any building or other improvement, other than those listed in section 12-8C-2 of this article. The natural area preservation district is intended to ensure that designated lands remain in their natural state, including reclaimed areas, by protecting such areas from development and preserving open space. The natural area preservation district includes lands having valuable wildlife habitat, exceptional aesthetic or flood control value, wetlands, riparian areas and areas with significant environmental constraints. Protecting sensitive natural areas is important for maintaining water quality and aquatic habitat, preserving wildlife habitat, flood control, protecting view corridors, minimizing the risk from hazard areas, and protecting the natural character of Vail which is so vital to the town's tourist economy. The intent shall not preclude improvement of the natural environment by the removal of noxious weeds, deadfall where necessary to protect public safety or similar compatible improvements. The majority of the site, including the areas of 40% slopes, will be zoned NAP. This allows for the land area that is environmentally sensitive to be preserved as open space with no development to occur in this area. This helps to preserve wildlife habitat and protects the natural character of Vail. As a result, the proposed subdivision, facilitating the rezoning, is consistent with the NAP zone district. Plans for the development of the housing site have not been initiated at this time, and any development plan will comply with all applicable zoning regulations. (3) The extent to which the proposed subdivision presents a harmonious, convenient, workable relationship among land uses consistent with municipal development objectives; and Applicant Analysis: The proposal to subdivide and rezone the property to H and NAP furthers two major development objectives: Provision of employee housing Protection of environmentally sensitive land It is rare that these two often-times competing objectives can come together in one project. The proposal creates an opportunity for employee housing on a small portion of the developable portion of the property, while protecting the remainder by precluding development. That these two objectives can meet on this privately -owned property within Town of Vail boundaries, creates a unique opportunity to create a harmonious relationship among land uses. The subdivision is being proposed to generate a legal description for a current unplatted parcel of land. The parcel could be zoned and developed without the need for a subdivision, but the applicant believes its in the public interest to establish a formal boundary for the property. The property is also somewhat removed and isolated from other developed residential areas, reducing the impacts of any 9of13 future development on neighboring developed properties thus ensuring a harmonious relationship. As a result, the proposal is consistent with this criterion. (4) The extent of the effects on the future development of the surrounding area; and Applicant Analysis: Though the site is visible from the East Vail 1-70 interchange, it is relatively isolated from other uses in the vicinity. The only directly adjacent residential property is the Falls at Vail (formerly Pitkin Creek Townhomes). The Falls at Vail is zoned Residential Cluster and the land use designation is "Medium Density Residential." The Falls at Vail consists of 23 townhouses constructed in the early 1980s and three of the units are deed -restricted as employee housing units, based on the Town of Vail GIS data. Permitted uses allowed by the RC zone district are primarily residential uses, including EHUs, multiple - family, single family and duplex units. Some limited commercial uses are allowed by conditional use in the RC zone district. These residential uses are separated from any developable areas by the large tract proposed for NAP zoning. 10 of 13 The uses allowed by the H zone district are similar to those listed in RC, though EHUs are the only permitted residential use in the H zone district. Free-market dwelling units are allowed by conditional use and are limited to 30% of the GRFA constructed on the site. Similarly, limited commercial uses are allowed by conditional use, but generally only to serve the residential uses of the site. The property to the north is outside Town boundaries and is United States Forest Service land, and Town of Vail open space is located across the Interstate and Frontage Roads. There are a few residential properties far to the south of the property, across the Interstate and Frontage Roads, within the Bighorn/East Vail neighborhoods. The Booth Falls neighborhood is located relatively far to the west of the property. Any future development of Lot 1 as proposed in this subdivision will not preclude or inhibit development on any adjacent parcel of land and the proposed subdivision will not impact the future development of the surrounding area. (5) The extent to which the proposed subdivision is located and designed to avoid creating spatial patterns that cause inefficiencies in the delivery of public services, or require duplication or premature extension of public facilities, or result in a "leapfrog" pattern of development; and Applicant Analysis: The proposed subdivision is located within the Town of Vail boundaries, adjacent to a transit stop, and adjacent to existing residential development (The Falls at Vail). Public services are readily available to the Proposed Lot 1 and there will be no duplication or premature extension of public facilities. The proposed subdivision of this infill lot does not qualify as a leapfrog development pattern since it is currently zoned for development and is located in close proximity to other residentially developed properties, and all utilities and public services can be provided to the site. The proposal is to generate a legal description for the property and create an open space tract. No extension of infrastructure is being proposed with this subdivision. The property could be developed today with or without this proposed subdivision. The proposed subdivision complies with this criterion. (6) The extent to which the utility lines are sized to serve the planned ultimate population of the service area to avoid future land disruption to upgrade undersized lines; and Applicant Analysis: Utilities are available in the general vicinity, and while some extension of services or upgrades to aging utility lines may be required, they will ultimately serve the future development of the project. The applicant of the future housing project will work with all utility providers prior to obtaining approval of any development proposal. 11 of 13 (7) The extent to which the proposed subdivision provides for the growth of an orderly viable community and serves the best interests of the community as a whole; and The proposed subdivision provides for the growth of an orderly viable community by establishing a site for employee housing within the Town of Vail boundaries, close to existing services and transportation, while simultaneously protecting the environmentally sensitive portion of the site. Employee housing is key to ensuring that the Town of Vail remain economically viable and competitive, while protecting the environmentally sensitive lands that have created a place worth living in. This does not constitute spot zoning, as both zone districts help further these goals and because the entire property is already zoned for residential uses. As a result, the proposed amendment serves the best interest of the community. (8) The extent to which the proposed subdivision results in adverse or beneficial impacts on the natural environment, including, but not limited to, water quality, air quality, noise, vegetation, riparian corridors, hillsides and other desirable natural features; and Applicant Analysis: The proposed subdivision and rezoning allows for the future development of the portion of the site that is buildable, while protecting the majority of the site in its natural state as undevelopable and protected. This allows for a project that can protect the natural environment, including the steep hillsides in excess of 40%. As part of this submittal, a wildlife report and geohazard report have been included. The wildlife report, by Rick Thompson of Western Ecosystems, Inc., evaluated the potential development site (portion zoned H) to analysis the impacts to local wildlife populations. The report identifies that based on CPW mapping, bighorn sheep and elk are of specific concern for the site. With regard to bighorn sheep, the report states: The relatively small potential East Peak [this East Vail property] development would result in a further loss of winter range, but its location in an area whose habitat effectiveness has been reduced by existing human disturbance and development should not result in any measurable change in habitat use or herd size. In the review of the impacts on the elk population, the report states: Similar to sheep, the relatively small potential East Peak [this East Vail property] development would result in a further loss of winter range, but its location in an area whose habitat effectiveness has been reduced by existing human disturbance and development should not result in any measurable change in habitat use or herd size. Approximately 75% of the parcel would remain available for continued elk use. The geohazard report was completed by Cesare, Inc, and was prepared in accordance with the Town of Vail hazard regulations and mapping. The report focuses on rockfall and landslide hazards on the 12 of 13 site. Recognizing that there is evidence of rockfall events on the property, the report does recommend rockfall remediation, stating: Based on the CRSP analysis results and existing rockfall mitigation structures on the neighboring site to the west, a rockfall barrier or wall at least12 feet in height is recommended. Based on site conditions, including such aspects as slope angle and property boundaries, a rigid wall system would be more ideal than a flexible fence or berm/basin. In reviewing any landslide considerations for the property (the east portion of the site), the report states: Based on the lack of evidence of recent landslide movement... Cesare does not recommend monitoring of the landslide at this time. Slope stability should be a primary consideration if ground modifications and development are planned in or near the landslide mass. The geohazard report also recommends that debris flow hazard potential be considered in future development stages. Booth Falls rockfall mitigation berm Because the entirety of the site is currently zoned for residential development, the proposed subdivision and zoning would limit future development to the eastern portion of the site, with the majority of the property zoned to preclude development, and as a result the proposed subdivision results in a net beneficial impact to the natural environment and complies with this criterion. (9) Such other factors and criteria as the commission and/or council deem applicable to the proposed subdivision. Applicant Analysis: Any other factors can be addressed as necessary. 13 of 13 a 0- cn -2 T Ett, n-0 Cf] C/I C/I 1 1 mill 44 C/I C/I C/I U) 0 < co a- U) z Z U) LL O -17 F- W Z c) Of 0 ILL 0 O � s M,eo ss.�os O .8£'6ZZ m P O M„b 1, IS.IOS �h a� 3 do �� �/ �/ M //� OO �i m� vl ® z � � � 1 (y�(� r�r,��, ��� 3a h � � � 2y � r�r��, vl 4 N ® = M 6�S F[Z Sti6ti 16ryf. Zob<� � � � \� Q W � 3 ry ry � s Soo d e �� ��® `o _ hM � e �O ®�o� ��� ��hp?pp _, �a� �� �� ^� � tCC� � C� 11 3� r1rq �1 � � � S� Q r� �1 �T ^�6 ti 3 M hh 0 x ATTACHMENT E - ROCKFALL HAZARD STUDY, PART 1 OF 3 ESARE, INC. Geotechnical Engineers & Construction Materials Consultants ROCKFALL HAZARD STUDY East Vail Parcel Vail, Colorado ,.� � � •tom 77, Report Prepared for: Mr. Kevin Hopkins Vail Resorts Development Company PO Box 959 Avon, CO 81620 Project No. 17.5029 June 19, 2017 7108 South Alton Way, Building B Centennial, Colorado 80112 www.cesareinc.com Phone 303-220-0300 1 Fax 303-220-0442 C"4ESARE, INC. Geotechnical Engineers & Construction Materials Consultants ROCKFALL HAZARD STUDY East Vail Parcel Vail, Colorado Report Prepared for: Mr. Kevin Hopkins Vail Resorts Development Company PO Box 959 Avon, CO 81620 Project No. 17.5029 June 19, 2017 Report Prepared by: Julia M. Frazier, P.G. Senior Geologist 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 CESARE, INC. TABLE OF CONTENTS 1. INTRODUCTION......................................................................................................................... 3 2. SCOPE OF WORK........................................................................................................................ 3 3. SITE CONDITIONS..................................................................................................................... 3 4. GEOLOGIC SETTING................................................................................................................ 11 4.1 REGIONAL GEOLOGY............................................................................................................... 11 4.2 SITE GEOLOGY........................................................................................................................ 12 4.2.1 ARTIFICIAL FILL (AF)....................................................................................................... 12 4.2.2 COLLUVIUM (QC)............................................................................................................. 12 4.2.3 LANDSLIDE DEPOSITS(QLS)............................................................................................. 12 4.2.4 PINEDALE TILL (QTP)....................................................................................................... 12 Robinson Limestone Member (Pmr)....................................................................................... 13 LowerMember (Pml)............................................................................................................ 13 5. GEOLOGIC HAZARDS............................................................................................................... 14 5.1 ROCKFALL............................................................................................................................... 16 5.2 LANDSLIDE............................................................................................................................. 16 6. ROCKFALL ANALYSIS............................................................................................................... 18 6.1 ROCKFALL STUDY SECTION...................................................................................................... 18 6.2 ROCKFALL MODELING - CRSP ANALYSIS.................................................................................... 24 6.3 ROCKFALL ANALYSIS RESULTS................................................................................................. 26 6.4 DISCUSSION OF ROCKFALL ANALYSIS RESULTS......................................................................... 26 7. LANDSLIDE HAZARD MAPPING............................................................................................... 27 8. CONCLUSIONS AND RECOMMENDATIONS.............................................................................. 28 8.1 ROCKFALL CONSIDERATIONS................................................................................................... 28 8.1.1 PLACEMENT OF THE ROCKFALL CATCHMENT STRUCTURE ................................................... 28 8.2 LANDSLIDE CONSIDERATIONS................................................................................................. 29 8.3 DEBRIS FLOW CONSIDERATIONS.............................................................................................. 30 9. LIMITATIONS.......................................................................................................................... 30 TABLES AND DIAGRAMS DIAGRAM 1. Cross Section D-D'.................................................................................................. 14 TABLE 1. CRSP Simulation Parameters....................................................................................... 25 TABLE 2. Slope Profile Parameters.............................................................................................. 25 TABLE 3. Summary of Rockfall Analysis Results......................................................................... 26 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 1 CESARE, INC. FIGURES SITE LOCATION MAP........................................................................................................ FIGURE 1 TOPOGRAPHIC MAP.......................................................................................................... FIGURE 2 OFFICIAL ROCKFALL HAZARD MAP, TOWN OF VAIL, COLORADO .................................... FIGURE 3 OFFICIAL DEBRIS FLOW HAZARD MAP, TOWN OF VAIL, COLORADO .............................. FIGURE 4 GEOLOGICMAP................................................................................................................. FIGURE 5 LEGEND FOR FIGURE 5 GEOLOGIC MAP........................................................................... FIGURE 6 LANDSLIDE EXTENTS MAP................................................................................................ FIGURE 7 STUDY SECTIONS MAP..................................................................................................... FIGURE 8 ROCKFALL STUDY SECTION.............................................................................................. FIGURE 9 LANDSLIDE STUDY SECTION.......................................................................................... FIGURE 10 SLOPEMAP..................................................................................................................... FIGURE 11 APPENDIX REFERENCES.................................................................................................................APPENDIX A ROCKFALL HAZARD ASSESSMENT AT BOOTH FALLS CONDOMINIUMS AND PROPOSED MITIGATION (COLORADO GEOLOGICAL SURVEY).......................................................APPENDIX B 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 CESARE, INC. 1. INTRODUCTION This report presents the results of a rockfall hazard study for an undeveloped lot located on the east side of Vail, Colorado and owned by the Vail Resorts Development Company (Vail Resorts). It is Cesare, Inc.'s (Cesare's) understanding that a preliminary rockfall hazard analysis is desired prior to potential development of the western portion of this site, along with other geologic hazards which may have a significant impact on the proposed development. The site is located directly north of the I-70 East Vail interchange. Geologic hazards, such as rockfall, debris flow, and avalanche are recognized by the Town of Vail and delineated in the project area. The rockfall hazard has been identified and addressed on the neighboring development to the west (Booth Falls Mountain Homes), with multiple existing catchment structures. 2. SCOPE OF WORK The scope of services for this rockfall hazard study generally included: 1. Review of available information, including published geologic maps, aerial photography, and readily available studies performed on nearby sites. 2. Site reconnaissance to verify geologic and geologic hazard conditions on and upslope from the subject site, with a focus on rockfall. This involved mapping the geology and geologic hazards by traversing the site on foot, and through photography and video of the site using an unmanned aircraft system (drone). 3. Modeling of the rockfall hazard potential using a critical cross section through the project site and input into the Colorado Rockfall Simulation Program (CRSP). 4. Preparation of this report presenting our findings and preliminary recommendations relative to the rockfall hazards potentially impacting the site, including conceptual techniques that might be used to remediate and reduce the rockfall hazard. Also included in this report are applicable figures, tables, and cross sections. 3. SITE CONDITIONS The project site is located directly north of the I-70 East Vail interchange on the north side of Fall Line Drive (Figure 1). Pitkin Creek Townhomes (formerly named Falls at Vail) is located immediately adjacent to the site in the southeast corner, and Booth Falls Mountain Homes (Booth Falls) and Vail Mountain School are located on a neighboring property to the west-northwest. The site is rectangular in shape and is located in the southeast 1/4 of Section 2, Township 4 South, Range 80 West of the 6th Principal Meridian in Eagle County, Colorado. The approximate center of the property is situated at latitude 390 3846" N and longitude -1060 18' 25" W. Cesare performed site reconnaissance to characterize and map the geologic and geologic hazard conditions during May 2017. The site is currently undeveloped with a variably sloping ground surface ranging from about 7 to over 45 degrees (Figure 2). The elevation ranges from about 8375 feet in the west side of the site to about 8940 feet in the northeast corner, an elevation change of about 565 feet across the site. The site is bound by undeveloped National Forest Service land to the north, northwest, and east. Fall Line Drive and the I-70 Frontage Road bound the site along the southern edge. Pitkin Creek forms a deeply incised drainage immediately to the east of the eastern site boundary. Booth Creek, also deeply incised, is located about 3,200 feet to the northwest of the site. Gore Creek is located on the opposite side of I-70, about 580 feet to the 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 3 CESARE, INC. south at closest approach. A retaining wall borders the site along Fall Line Drive near the East Vail I-70 off ramp in the area of the shuttle stop. Design or construction details for this retaining wall were not available at the time of this study. Based on site observations, this retaining wall is constructed of wood cribbage, with gravel placed directly behind the wood facing. The wall appears to generally be in good condition, with one exception near the east end where the wall has bulged out. An unpaved, single track road traverses the site along the edge that borders Fall Line Drive and is barely visible in some historic aerial photographs. Multiple utility service manholes were observed along this single track road and the manhole covers are labeled with Alelectric utility". Vegetative cover at the site includes grasses, shrubs, and aspen trees. The western part of the site and the area upslope of the western part of the site are incised with a network of drainages which contained flowing water at the time of our site visits. This western area is generally more densely vegetated with low shrubs and aspen trees than other parts of the site and upslope areas. Refer to Photographs 1 through 8 for views of these onsite features. Photograph 1. View of the project site. Photograph taken from the eastbound lane of I-70 looking east across the site. The photograph shows the relatively steep slope of the site and the rock outcrops present upslope from the site. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 4 Aft Photograph 1. View of the project site. Photograph taken from the eastbound lane of I-70 looking east across the site. The photograph shows the relatively steep slope of the site and the rock outcrops present upslope from the site. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 4 CESARE, INC. rw �y -t Photograph 2. View of 1 retaining wall located along edge of site that borders Fallr Line Drive. Town of Vail shuttle 1 i stop is visible in the left side of the photograph. w Photograph 3. View of distressed part of the retaining wall along the edge of the site that borders Fall Line Drive. The slope rises steeply upward to the north at the top of the wall. This photograph was taken near the east end of the wall. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 5 CESARE, INC. i 7 B Cp } Z• L O 0 -0 U) 0) 0) � � a 70 }' O O O Cl O a) N V C � O .� 0 N > Q � c1 i C O to -a ro N � Q O F 70 U) .U) O � L 0 � a a--+ _0O 0 0 4U- U) L � L i � 0 4- V a--+ (o -2=o 0 0 ro L U V V 'E a) L U) a-+ -0 0 " E 4.1 O L L +- � L L V O V O 5 0 Q �> s 0 o O 0 0 4- fl s '� o 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 6 CESARE, INC. Photograph 5. View of limestone boulders which have come to rest near the base of the slope in the western part of the site. Boulders are about 3 to 4 feet in longest dimension, embedded in the soil, surrounded by mature vegetation, and show lichen on the surface. - 12 =Mr Photograph 6. View of large sized limestone boulder located in the southern area of the site. Boulder measures about 21 feet long by 16 feet wide by 6 feet high. A survey marker has been placed on this boulder (Eagle County Survey Control, 1998). 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 7 CESARE, INC. Photograph 7. View of the western part of the site. Note the dense vegetative cover, flowing water, and exposed bedrock outcrops near the top of the slope. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 Photograph 8. View of flowing water in the western part of the site. CESARE, INC. Rock outcrops are present upslope from the site and are rockfall source zones which have the potential to impact the site and future planned development. Rockfall is a recognized hazard in the site area, as depicted on the "Official Rockfall Hazard Map" for the Town of Vail (Figure 3). A significantly sized rockfall catchment berm and basin, located about 1,300 feet to the northwest at closest approach, has been constructed to reduce the rockfall hazard above the Booth Falls development. It is Cesare's understanding that this consists of an earthen berm ranging in height from about 10 to 15 feet, and an upslope catchment area spanning about 20 feet where the natural slope has been laid back. An access road leading up to the catchment area begins at Fall Line Drive near the western point of the project site. Additional rockfall remediation structures are located upslope from Booth Falls Court and are visible in the aerial imagery. These rockfall remediation features are shown in Photographs 9 through 11. Debris flows are also a recognized geologic hazard for the area, as shown on the "Official Debris Flow Hazard Map" for the Town of Vail (Figure 4). As shown on Figure 4, the site is not within a debris flow hazard zone, although moderate and high hazard areas are delineated along Pitkin Creek to the east-southeast of the site. Photograph 9. Google Earth image of Booth Falls Mountain Homes to the west of the project site. Examples of existing rockfall remediation structures are labeled. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 9 CESARE, INC. "A a r1k' .et�+lR� yr� yr' ^;q � � ..yam►, y '. 7' ✓,Y •11s 1iJ�i1%�..SYi, '•y 5 .: . ` ry 1 �ilz c x KE" a -,T'�'1. � �k ♦�"' rya �Ar! �.k�SS -;,�'v � �' ��r - ?� �� � - f� /` ria\ �K • a:I tip_ tt�?r - ksie�s!?, -i� ADb�P �rr his r� 4� s yyF �i � � 4 t '� ]��Pr '-3x ����. � tn. � ���"'D syr r✓ m � � Photograph 10. View of rock -fall catchment berm and basin, upslope from Booth Falls Mountain Homes. View looking west toward Booth Creek. The berm is between 10 and 15 feet high, and the ditch is about 20 feet from crest of berm to backslope. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 10 CESARE, INC. ak^ �; a AV kn fir, .S ixi Photograph 11. View of rock -fall catchment berm and basin upslope from Booth Falls Subdivision. View looking east toward the project site. 4. GEOLOGIC SETTING 4.1 REGIONAL GEOLOGY The site is included in the Southern Rocky Mountain physiographic province in an alpine setting with elevations ranging from 8000 to 9000 feet. The site is located along the western flank of the Gore Range, a northwest -southeast trending mountain range situated in north -central Colorado. The Gore Range is separated from the Front Range Mountains to the east by the Blue River Valley and Williams Range thrust zone. The core of the Gore Range is comprised of crystalline basement rock uplifted during the Laramide mountain building event (orogeny) about 70 to 50 million years ago (Ma). The Laramide orogeny also uplifted thick sequences of sedimentary units deposited during the occupation of an inland sea in parts of Colorado. The sedimentary units are comprised of shale, claystone, siltstone, sandstone, conglomerate, and limestone. The Gore fault is located about 500 feet northeast of the site at closest approach and is not considered active (Figures 5 and 6). The Gore fault is characterized as a zone of high angle reverse faults. These faults have had at least five episodes of movement that span from Precambrian (older than 540 Ma) to late Oligocene and younger (about 28 Ma), although most of the displacement likely took place during the Laramide orogeny (Kellogg and others, 2011). A 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 11 CESARE, INC. gentle regional tilt of 5 to 15 degrees down to the south-southwest, characterizing the sedimentary bedrock in the site vicinity, is interrupted adjacent to the Gore fault. Beds of the Minturn Formation are steeply dipping and overturned where located close to the Gore fault, as is the case upslope and to the northeast of the site. 4.2 SITE GEOLOGY The site is underlain by surficial units comprised of artificial fill, colluvium, landslide deposits, and till of the Pinedale glaciation (Figure 5 Geologic Map). The bedrock underlying the site is mapped as Minturn Formation (Kellogg and others, 2003; Kellogg and others 2011). Artificial fill is associated with the construction of Fall Line Road along the southern border of the site and likely with the unpaved, single track road (with buried utilities) in the southwest part of the site. A wedge of colluvium is mapped mid -slope in the western half of the site, however, the colluvium was actually observed to completely cover the site and largely obscure bedrock outcrops. The eastern half of the site is predominantly landslide deposit and Pinedale Till underlies the southeastern corner of the site. Bedrock of the Minturn Formation underlies the surficial deposits at the site. Descriptions of these units are described below, from youngest to oldest. Refer to Diagram 1 for a geologic cross section near the site. 4.2.1 Artificial Fill (afi) Artificial fill is associated with the ground modifications that have occurred within and adjacent to the site boundaries. Based on site observations, artificial fill is likely associated with the single track utility road in the southwestern part of the site, construction of Fall Line Drive, and construction of the shuttle stop and retaining wall in the southeast part of the site. 4.2.2 Colluvium (Qc) Colluvial deposits (Holocene and upper Pleistocene; 126,000 years ago to present) cover most of the slope in the site area based on site observations. Colluvium is characterized as unconsolidated, generally non -stratified deposits mantling slopes less than 50 degrees. Colluvial deposits are comprised of pebble, cobble, and boulder sized rock and fine grained material mixed together by downslope movement. Colluvium is typically less than about 30 to 45 feet thick. 4.2.3 Landslide Deposits (Qls) Landslide deposits (Holocene and upper Pleistocene; 126,000 years ago to present) underlie most of the eastern half of the site. Kellogg and others (2003) characterize these mapped deposits as a range of chaotically arranged debris to intact slump blocks of bedrock. The middle member of the Minturn formation (Pmm) is notably susceptible to landsliding, although slope failures can occur in most sedimentary units where over steepening of the ground surface has destabilized slopes. Largescale landslide deposits may be up to about 120 feet thick. 4.2.4 Pinedale Till (Qtp) Glacial till of Pinedale age (upper Pleistocene; 126,000 to 11,000 years ago) underlies the southeast corner of the site and also a majority of the slopes to the east-southeast, and the area upslope to the north of the site (in part). Pinedale Till is characterized as unsorted, unstratified, and boulder. It tends to form hummocky topography with common depressions and small ponds. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 12 CESARE, INC. Till deposits were observed upslope from the site and were bouldery (sedimentary and igneous composition) and poorly sorted. This unit has been mapped as high as 900 feet above the present elevation of Gore Creek, with thickness up to about 90 feet. 4.2.5 Minturn Formation The Minturn Formation (middle Pennsylvanian; 315 to 307 Ma) underlies the entire site and general vicinity. This unit is generally comprised of conglomerate, sandstone, siltstone, claystone, shale, and stratigraphically distinct layers of limestone and dolomite. The Minturn Formation is divided into multiple units, two of which directly underlie the site: Robinson Limestone Member (Pmr) Marine limestone and dolomitic limestone, gray to yellow gray, fine to medium grained, and locally contains fossils. Comprised of four separate sequences (each about 60 feet thick) of limestone interbedded with pinkish tan, light tan, cross bedded, mica rich sandstone and grayish pink sandy siltstone and shale. The sandstone, siltstone, and shale layers weather in rounded forms, and the limestone and dolomite beds weather in relatively angular forms. Outcrops of the Robinson Limestone member are visible in the steep cliffs northwest and are also exposed directly upslope from the site. One large boulder dislocated from upslope and came to rest near the base of the slope along Fall Line Drive is sandstone containing purple gray coral, possibly representative of a reef facies within the Robinson Limestone member. The Robinson Limestone member is about 360 feet thick north of Gore Creek. Lower Member (Pml) Conglomerate, sandstone, siltstone, and shale, pinkish gray, gray brown, gray green, mottled maroon, and gray green. The Lower member may contain clasts of Proterozoic age granite (2,500 to 541 Ma). This unit is generally obscured by vegetation onsite and outcrops were not identified during our site visits. The Lower member of the Minturn Formation can be up to about 1,200 feet. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 13 CESARE, INC. DIAGRAM 1. Cross Section D -D' D D, FEET FEET 12.000 approximate downslope approximate upslope tz.voo Ppm extent of site extent of site 11,000 Q` Pmj GORE FAULT SYSTEM 11.000 --- ---- --------------- - - - 10,000 X9 ml % 9.000 i1 9.000 Xu 7,000 Some thin s0iciel cepon% not sham 700o Qa Alluvium (Holocene) 0c . Colluvium (Holocene and upper Pleistocene) otp Pinedale Till (upper Pleistocene) atb Bull Lake Till (middle Pleistocene) F'iPui Manxm Formation (Lower Vermian to Middle Pennsylvanian) �m Minlurn Forrrtatinn, smdi(feranlialed (Midd3e Pennsylvanian) Pm( Jacque Mountain Limestone Member Lipper sandstone and conglomerate member �mwq While Quail Limksiune Member �rnm Middle member X01111 Individual Iinurstone bed Prnr Robinson Limestone Member rl Individual limestone bed Lower member 4�mis Individual limestone IMI Xg I Cross Creek Granite Cross section D -D' excerpted from the Geologic Map of the Vail East Quadrangle (Kellogg and others, 2003). This cross section is located immediately east of the project site and schematically depicts the surface and subsurface geologic conditions in the site area. S. GEOLOGIC HAZARDS The current study focused on the geologic hazard related specifically to slope stability, including rockfall and landslides in particular. Rockfall was analyzed using the Colorado Rockfall Simulation Program (CRSP) for one study section located on the west side of the site where development is most likely (per client communication). The landslide hazard was characterized primarily through review of published maps and site reconnaissance to verify the nature, extents and evidence of recent movement. Debris flows are a significant potential hazard in the site vicinity, although debris flow susceptibility has not been determined for Vail or Summit County to date. The site is not included in the Official Debris Flow Hazard Map for the Town of Vail, although Pitkin Creek located near the southeast corner of the site is considered to have moderate to high hazard potential. One debris flow located on the east -facing slope of Booth Creek (about 3,700 feet from the western site boundary) and visible from the site is shown in Photograph 12. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 14 CESARE, INC. Photograph 12. View looking west toward Booth Creek. The project site is located beyond the trees in the right side of the photograph. Features are labeled. Debris flows and rockfalls have damaged buildings in the Gore Creek area since development increased in the 1960's. Debris flows can be triggered by intense summer rainstorms or rapid melting of deep snowpack. Debris flows generally form on fan deposits, such as those composed of glacial till. Freeze -thaw cycles in the spring tend to pry rocks loose, resulting in rockfalls of varying magnitude and runout distance. The rockfall hazard is also related to a combination of weak shale beds between harder sandstone and limestone beds, joints, and a regional bedrock dip toward the valley. Large boulders from cliffs comprised of the Robinson Limestone member of the Minturn Formation fell and damaged several residences in the Booth Falls subdivision in the 1980's. As a result, the homeowners and Town of Vail created a Geologic Hazards Abatement District (GHAD) which aided in construction of a rockfall catchment ditch and berm that has generally proven to be an effective protection measure (shown in Photographs 9 through 12). The exception would include the event in 1997 when a large scale rockfall skirted around the western end of the catchment structure, rolling downslope, and damaging structures below. This event resulted in the construction of mechanically stabilized earth (MSE) walls to add protection for the downslope condominiums (some of which were not included in the original GHAD). A report issued by the Colorado Geological Survey (CGS; undated) summarizes the event: 'At 11:20 p.m., a ledge of Minturn Formation limestone at the highest exposed outcrop of the upper cliff, just below the exposure of glacial t111, failed similarly to that shown in Figure 3 of Appendix A. The ledge dimensions that detached and toppled is roughly 20' x 8' x 8: As it fell, it impacted and broke additional rock blocks from outcrops below. The rock mass broke apart as it tumbled down the cliff. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 15 CESARE, INC. As it fell down the slope, the rock fragments randomly fanned out such that the ,Hath of the rockfall formed a swath more than 500 feet across where they came to rest. [..] Approximately one third of the swath of rolling rocks were retained by the ditch and berm. [..] The remaining two-thirds of the event came to rest, scattered around the condominiums " 5.1 ROCKFALL Rockfall is a potential hazard for the site and poses a risk to the property. Rockfall is the fastest category of slope movement and is common in mountainous terrain near cliffs of broken, jointed, or faulted rock, on steep slopes comprised of rocky material, or where cliff ledges are undercut by erosion or human activity. Stability of a rock mass is generally influenced by the underlying support provided to that rock mass and the structural nature of the rock, including the orientation and spacing of discontinuities. After a rock dislocates from a rock mass, the controlling factors for how far that rock will travel downslope include characteristics of the falling rock (composition, size, and shape), characteristics of the slope (form, length, and angle), the presence or absence of obstructions on the slope, and the height of the initial fall. The rocks exposed upslope from the project site are comprised of the Robinson Limestone member of the Minturn Formation. The rock exposures contain fractures and thin layers of siltstone and shale. As time passes, cracks can be enlarged by weathering of the rock, accumulation of soil or vegetation growth, and the forces associated with freezing -thawing of moisture within the cracks. 5.2 LANDSLIDE Landslide deposits in the area occur on unstable slopes typically underlain by Minturn Formation shale, siltstone, claystone, or glacial till, and are largely considered inactive. The extents of a large landslide onsite were mapped during field visits, and the published boundaries were verified and refined using available light detection and ranging data (LiDAR). Refer to Figure 7 for the approximate landslide extents mapped for this study. Geomorphic features across the landslide have been masked by heavy vegetative cover, and obscured and smoothed by natural processes. The block sliding mechanism responsible for parts of the landslide mass enable large, relatively intact bedrock masses to slide downslope. These masses may appear to be in-place, when in fact they have moved downslope from their original position. Based on the high level of detail offered by the LiDAR view, Cesare has confidence in the mapped extents of the landslide as depicted in Figure 7. The toe of the mapped landslide deposit is abruptly cut off by Fall Line Drive. The downslope extents and western flank of the landslide are steep and form a recognizable break in slope shown on the topographic map (Figure 2) and on the LiDAR (Figure 7). Photograph 13 is a view of the landslide toe and western flank, looking eastward. The retaining wall built near the Town of Vail shuttle stop is about 10 feet high and the slope above the top of wall is relatively steep (30 degrees or greater). According to Kellogg and others (2011), a large landslide was activated on the north side of I-70 due to undercutting from highway construction. The landslide is located about 1.5 miles west of the project site on I-70, involves the Minturn Formation (same unit that 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 16 CESARE, INC. underlies the subject site), and is failing by combination of shallow earth sliding and deep rotational movement. y� ZS My !Y ~ tip y _ Photograph 13. View looking eastward from the western flank of the landslide toe. The ground surface is relatively steep along the toe and flanks of the slide mass, visible in the photograph. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 17 CESARE, INC. 6. ROCKFALL ANALYSIS 6.1 ROCKFALL STUDY SECTION Cesare analyzed one rockfall study section through the west part of the site (Figure 8). The location of this rockfall study section is representative of the slope on the west side and passes through the area of the project site most likely to be developed in the future. The rockfall study section is considered a reasonable representation of the slope in the western part of the site. The section profile was derived from topographic maps available through the USGS, the Town of Vail, and a topographic map for a portion of the western part of the site provided by the client. The rockfall study section is depicted on Figure 9 and shown in Photographs 14 and 15. Photograph 14. View looking upslope along the rockfall study section. Notable features include the limestone bedrock exposures visible at the top of the slope and the dense vegetation on the slope. The limestone bedrock forming the cliffs at the top of the slope are considered the primary rockfall source zone. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 18 CESARE, INC. Y y ` = law Photograph 15. View looking downslope along the rockfall study section. Notable features include the rock exposures visible at the top of the slope, the steepness of the slope, and the density of the vegetation. Fall Line Drive, I-70, and East Vail are visible in the background. The rockfall study section begins upslope above the primary rockfall source area exposed in the cliff comprised of Robinson Limestone and extends southward to Fall Line Drive, with a total elevation change of about 760 feet over a profile length of 1,530 feet. The analysis for the rockfall study section assumes the rockfall source zone is located in the exposed cliff face upslope from the site at an elevation of about 9040 to 9080 feet. Photographs 16 through 18 show the limestone bedrock exposed in the cliff face upslope from the site. Bedrock exposures (potential rockfall source zones) were not observed further upslope from this area, although the glacial till deposits above the primary rockfall source zone may be eroding and contributing to the rockfall hazard. The slope above the western part of the project site is incised with active drainages and covered in aspen trees, tall shrubs, and scattered boulders and outcrops. Rocks deposited along the rockfall study section slope are primarily blocky to slab shaped, and comprised of gray limestone interbedded with thin layers of sandstone, siltstone, and shale. Boulders comprised of sandstone were also observed. The rockfall study section appears to be an area of more recent rockfall events, compared to other areas of the site. A number of rocks in the rockfall study section area display a comparatively "fresh" appearance, relative lack of lichen or vegetative overgrowth, and some with minimal soil embedment. For other parts of the slope, a majority of the boulders are more deeply embedded in the soil and overgrown with lichen and vegetation (indicating much older rockfall events). Refer to Photographs 19 through 23 for examples of boulders observed on the ground surface in the area of the rockfall study section. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 19 CESARE, INC. Photograph 16. View of limestone bedrock exposure at the primary rock -fall source zone. Note the eroding shale partings and vertical fractures (spaced about 10 to 15 feet apart). r_— Photograph 17. Close-up view of ` primary rock -fall source zone bedrock. Gray, hard limestone interbedded with thin, weak shale layers. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 20 CESARE, INC. O 0 o U) fo ..F - �� rr-J O N 0 L a) - Cnfo cn 4-0 - - ! .lr — r� fo { - _ 21 E o to O O -0 _ p L C V -- —_ _ p • --'lL _ i_f ' -_ice - - ~ � - 2 � � iii i _ -. s : _ _ - _ _ i i•n . O O E # > O LL a�p3_ •' ti: f_� i O N T. "• r �a5a- ' — s 81 L 0 (n E 4- 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 21 CESARE, INC. Photograph 19. View of limestone boulder, embedded. Blocky, angular, and about 3 feet in diameter. Boulders like this one are common on the property and are either embedded in the soil (older, ancient rock -fall events) or are sitting on top of the soil with minimal soil embedment or vegetation overgrowth. Photograph 20. Limestone boulder, embedded, lichen growth. Blocky, angular, and about 4 foot by 3 foot by 2 foot. Photograph 21. Limestone boulder, minimal soil embedment. Blocky, angular, and about 3 feet in diameter. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 22 CESARE, INC. Photograph 22. View of large, angular, slab shaped boulders near the base of the slope within the area most likely to be developed in the future. Boulder sizes were observed to be at least (1) 12 foot by 8 foot by 5 foot, (2) 7 foot by 7 foot by 3 foot, and (3) 21 foot by 12 foot by 9 foot. These boulders are embedded in the soil and have been resting here for some time. ... �• . � ...� � ,�.�� - �� �s° -,_ � t .0`3�' ..` 4; �y is '- .�?� .'�'.?' '� ..' ry �, - - .d" iiiIL I Photograph 23. Aerial view of lower slope in western part of the site. North is toward the top of the photograph. Notice scattered boulders as large as about 7 to 8 feet in longest dimension and slab shaped. Most boulders are 3 feet or less in dimension and are embedded in the soil, representing older, ancient rock -fall events. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 23 CESARE, INC. 6.2 ROCKFALL MODELING - CRSP ANALYSIS Factors which influence the runout distance, mode of travel, speed, and energy of a rock traveling downslope include: • Type, size, and shape of the rock. • Type, length, height, and angle(s) of the slope. • Potential launch points along the slope. • Presence of obstructions on the slope (including trees, shrubs, and existing boulders). • Height of the initial fall. Based on site observations, the types of rocks traveling down the slope are comprised primarily of blocky to slab like limestone. Rocks are also comprised of sandstone to pebble conglomerate and a minor percentage of small, granite boulders (derived from the glacial till capping the slopes above the cliff -face rockfall source zone). Sizes generally range from about 2 to 6 feet in diameter, but can be as large as 20 to 30 feet in longest dimension. The larger dimension rocks are slab shaped, irregular, with angular corners. The falling mechanism for the slab shaped rocks would be primarily sliding after detachment from the source rock, although these rocks may roll downslope end -over -end along the shorter dimension. Based on our experience with similar conditions, site observations, and on opinions presented by the CGS for the rockfall hazard at Booth Falls to the west of the project site, the limestone rocks falling from the cliff source zone tend to break apart during their descent downslope. Cesare opines that some of the larger blocks on the scale of 20 to 30 feet in diameter may have been entrained in block slide movement of the landslide complex onsite. CRSP requires that the section analyzed be divided into regions (cells) based on areas with uniform slope and characteristics. Cell boundaries are determined based on characteristics, such as slope angle, material comprising the slope, and the presence of obstructions. Surface roughness was estimated with consideration for the size of the rock and the irregularity of the slope surface. The surface roughness (S) is defined as the perpendicular variation of the slope within a slope distance equal to the radius of the rock. This value varied based on rock size analyzed. Based on site observations and available topographic maps, there are no significant launch points below the rockfall source zone along the section. The tangential coefficient of frictional resistance (Rt) for the rock is the component of velocity parallel to the slope, which is slowed during impact. The tangential coefficient was chosen with consideration for the material which comprised the slope, as well as the amount of vegetation characteristic in each cell. Vegetation would tend to increase the frictional resistance in the direction parallel to the slope, thus decreasing the tangential coefficient. The normal coefficient of restitution (Rn) considers the change in velocity of the falling rock normal to the slope after impact, compared to the normal velocity before impact. For both the Rt and Rn coefficients for each cell, Cesare referred to the CRSP manual which provides ranges of suggested values based on different material types. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 24 CESARE, INC. Cesare calibrated the model using the current conditions of the slope (no rockfall barrier, native condition) and using rock sizes and shapes based on site observations. Simulation and slope profile parameters are listed in Tables 1 and 2, respectively. TABLE 1. CRSP Simulation Parameters Parameter Study Section A Length of section analyzed (ft) 1,530 Elevation difference across section (ft) 760 Total number of cells 6 Analysis Point 1 (x-coordinate) 1,000 Analysis Point 2 (x-coordinate) 1,200 Top starting zone (y-coordinate) 9,080 Base starting Zone (y-coordinate) 9,040 Number of rocks simulated 500 Starting velocity (x) 1 ft/sec Starting velocity (y) -1 ft/sec Material density of modeled rock 160 Ib/ft3 Rock shape Spherical Rock dimension (diameter) 10 Starting cell number 2 Ending cell number 6 TABLE 2. Slope Profile Parameters Rt: Tangential coefficient Rn: Normal coefficient Surface roughness varied based on rock size analyzed. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 25 Approx Cell Begin (x,y) Rt Rn Slope Angle Description of Slope Geologic Unit 0 1 0,9140 0.65 0.15 35 Vegetated slope above rock -fall Glacial till (Pinedale). source zone. 2 100,9080 0.85 0.20 Near Cliff face, rock -fall source zone, Robinson Limestone member vertical approximately 30 to 40 feet high. of the Minturn Fm. Vegetated slope below rock -fall Colluvium overlying 3 110,9040 0.70 0.15 30 source zone, runout accumulation Robinson Limestone/Lower zone. members of the Minturn Fm. 4 930,8540 0.60 0.15 20 Vegetated slope, accumulation Colluvium overlying Lower zone. member of Minturn Fm. 5 1180,8438 0.60 0.15 8 to 16 Vegetated slope, accumulation Colluvium overlying Lower zone. member of Minturn Fm. 6 1411,8382 0.90 0.60 Paved roadway Fall Line Drive, asphalt paved Not applicable. flat roadway. Rt: Tangential coefficient Rn: Normal coefficient Surface roughness varied based on rock size analyzed. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 25 CESARE, INC. 6.3 ROCKFALL ANALYSIS RESULTS The results of the analysis using the current condition of the slope are summarized in Table 3. Reported are results for common rock sizes observed at the site (3 feet diameter) and an estimated maximum case (10 feet diameter). Although boulders as long as 30 feet in longest dimension were observed embedded near the base area of the slope, these are considered more likely to have been placed during block sliding of the landslide mass. The rocks were modeled as spherical in order to represent the worst case scenario. Rocks which are spherical will tend to have longer runout distances and higher velocities and kinetic energies associated with them. Elongate, angular rocks will tend to lose momentum sooner than a rounded rock as they travel downslope. Analysis Point 1 was placed about 200 feet upslope from the property boundary and Analysis Point 2 was placed right at the upslope property boundary. Based on observed runout and accumulation zones and calibration analysis results, it is Cesare's opinion that the input values listed in Tables 1 and 2 adequately model the slope in question. Rockfall analysis results are listed in Table 3. TABLE 3. Summary of Rockfall Analysis Results AP = analysis point ft/sec = feet per second ft -Ib = foot-pounds 6.4 DISCUSSION OF ROCKFALL ANALYSIS RESULTS The CRSP analysis results show that a 10 foot diameter, spherical limestone boulder rolling downslope along the rockfall study section from a source zone between 9040 and 9080 feet elevation will have an estimated maximum kinetic energy of 1,846,786 foot-pounds (ft -Ib), an equivalent of about 2,500 kilojoules, at the upslope property boundary. The slope gradually 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 26 Number of Rocks Velocity (ft/sec) Bounce Height (ft) Kinetic Energy (ft -Ib) Kinetic Energy (kilojoules) P_TassiAP ng Max Avg Max Avg Max Avg Max Avg Rock Shape = spherical; Rock Size = 3 ft (2,262 pounds), API 492 37.6 19.2 4.3 0.7 65,545 18,906 90 26 AP2 21 16.9 8.0 0.3 0.1 13,957 3,649 19 5 Rock Shape = spherical; Rock Size = 10 ft (86,394 pounds) API 499 52.9 35.7 3.9 1.1 4,570,623 2,240,805 6,197 3,038 AP2 497 33.2 20.8 2.7 0.7 1,846,786 800,467 2,504 1,085 Rock Shape = discoidal; Rock Size = 12 ft diameter by 5 ft thick (90,478 pounds) API 499 46.7 37.6 3.4 1.0 4,112,846 2,861,685 5,588 3,880 AP2 499 33.8 24.7 2.6 0.8 2,243,475 1,270,950 3,042 1,723 AP = analysis point ft/sec = feet per second ft -Ib = foot-pounds 6.4 DISCUSSION OF ROCKFALL ANALYSIS RESULTS The CRSP analysis results show that a 10 foot diameter, spherical limestone boulder rolling downslope along the rockfall study section from a source zone between 9040 and 9080 feet elevation will have an estimated maximum kinetic energy of 1,846,786 foot-pounds (ft -Ib), an equivalent of about 2,500 kilojoules, at the upslope property boundary. The slope gradually 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 26 CESARE, INC. decreases between Analysis Point 1 and 2, resulting in a decrease in kinetic energy of a rolling rock between these points. The area of Cell Number 4 along the profile is a zonal transition from rockfall runout in Cell 3 to rockfall accumulation in Cell 5. For comparison, the worst case scenario considered in the CRSP analysis performed by the CGS for Booth Falls was a spherical boulder 7 feet in diameter with an impact force of 5,000,000 ft -Ib (about 6,800 kilojoules). This estimated energy is extreme when considering rockfall fences (flexible mesh barriers) currently on the market are rated for impacts up to a maximum of 8,000 kilojoules. The ground surface in the area of the slope analyzed at Booth Falls is generally steeper and vegetatively bare compared to the section analyzed for this study. CGS recommended the design height for the proposed rockfall mitigation structure be at least 12 feet, if placed at the analysis point located 30 feet upslope from the existing condominiums. An added option to mitigate for smaller rock fragments which tend to break from larger rockfalls, included adding a fence to the top of the berm or wall to be constructed. Cesare understands that for Booth Falls, a pair of soil walls reinforced with geotextiles and sized 8 feet high by 10 feet thick and 12 feet high and 12 feet thick were constructed after the 1997 rockfall event. The nature of the ground surface at the project site acts to dissipate rockfall energies compared to the slope above Booth Falls. The ground surface on the west side of the site is comparatively less steep, heavily vegetated with aspen trees and large shrubs, dotted with scattered, embedded boulders, with incised drainages that act to channel and slow rockfalls. Vegetation, incised drainages, and embedded boulders act to increase surface roughness of the slope, creating obstacles which decrease rockfall energies. Comparison of the ground surface characteristics and the CRSP results for both the project site and the neighboring Booth Falls indicates the rockfall hazard is higher for the Booth Falls area than for the project site. 7. LANDSLIDE HAZARD MAPPING The extents of a large landslide complex were mapped on the east side of the site (Figure 7). A landslide study section passes through the middle of the landslide, location shown on Figure 8 and profile shown on Figure 10. The landslide study section begins upslope above an exposed outcrop comprised of Robinson Limestone at about 8900 to 8920 feet elevation and extends southward to Fall Line Drive, with a total elevation change of about 588 over a profile length of 1,220 feet. The elevation of the Robinson Limestone bedrock exposure can be correlated to the rock exposures to the west which are the primary rockfall source zone for the Booth Falls subdivision, although the outcrop on the subject site is not as pronounced or as exposed as areas to the west. Based on the landslide morphology visible in the LiDAR image, this bedrock exposure at about elevation 8900 likely slid down from a higher elevation upslope. The LiDAR bare earth surface and the landslide study section both display a benched and hummocky pattern characteristic of landslide terrain. The flatter parts of the benched areas range from about 15 to 20 degrees, while the toe areas of the benches range from about 30 to 40 degrees. A slope map is shown on Figure 11 and depicts the range of slope angles across the site and surrounding area. 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 27 CESARE, INC. Cesare understands that the Pitkin Creek townhome development located southeast of the site and also at the toe of the mapped landslide extents has not reinforced the slope above the residences. It was beyond the scope of this study to research potential landslide movement causing distress to the Pitkin Creek development townhomes, and at this time Cesare is not aware of landslide movement or related structural distress in the southeast area of the site. Chen and Associates, Inc. (Chen) issued a soil and foundation investigation report for the proposed Pitkin Creek Townhomes (dated September 20, 1978) which included subsurface exploration using test pits to a maximum depth of 10 feet. The soils encountered were described as 1 to 3 feet of topsoil over dense, sandy gravel, with cobbles and boulders to the maximum depth explored. Groundwater was not encountered in the test pits. The Chen report mentions how the slope of the site rises steeply to the north and that several large boulders were observed on the ground surface, but does not discuss landslide or rockfall hazard or potential. 8. CONCLUSIONS AND RECOMMENDATIONS This report presents findings of a geologic hazard study specifically focused on rockfall. During the course of the study, a significant landslide hazard was identified and is discussed in this report. 8.1 ROCKFALL CONSIDERATIONS Based on the CRSP analysis results and existing rockfall mitigation structures on the neighboring site to the west, a rockfall barrier or wall at least 12 feet in height is recommended. Based on site conditions, including such aspects as slope angle and property boundaries, a rigid wall would be more ideal than a flexible fence or berm/basin. The flexible fence system would require a downslope buffer zone for flexure during rockfall events. A berm and basin system would require a significantly sized footprint on the slope, something this project site does not necessarily have flexibility towards. Cesare's CRSP model represents an estimate of rockfall energies at the analysis point placed at the upslope property boundary along the section line and is not representative of other locations on the slope. Changing the placement of the rockfall barrier will require changing the location of the analysis point. Rockfall energies were modeled to be significantly higher at Analysis Point 1 located 200 feet upslope from the property. A catchment zone large enough for accumulation of boulders and for equipment to access the area behind the barrier will be necessary, a width of at least 10 or more feet. It is the responsibility of the wall designer to provide criteria for a wall that will withstand impacts with the sizes and energies predicted by the CRSP analysis, and one which will allow for successful implementation of recommended maintenance requirements. For rigid rockfall walls similar to those constructed at the Booth Falls site, the height to width ratio is typically a 1:1 relationship. The rockfall catchment will be reducing the rockfall hazard for a potential residential development and should be designed with consideration for the nature of the structures (full-time occupancy). 8.1.1 Placement of the Rockfall Catchment Structure Factors which influence the placement of the catchment structure include the rockfall energies, sizes, shapes, and bounce heights estimated in the CRSP model for that analysis point on the slope. Other considerations include site topography, site boundaries, and the spatial footprint of the proposed rockfall catchment structure. The mitigation structure must provide an adequately 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 28 CESARE, INC. sized catchment zone behind the wall and a buffer zone in front of the wall. The catchment zone behind the wall must be sized to allow for accumulation of large boulders on the scale of 10 feet in diameter, as well as access for equipment to remove accumulated debris from behind the wall. Design considerations should include access for excavation equipment and adequate surface drainage. Based on topography, the west side of the property provides adequate access for a track mounted vehicle from Fall Line Drive and possibly a rubber tire vehicle (although access depends on actual site development/grading plans, not available at the time of this study). An adequately sized buffer zone in front of the wall is necessary in order to allow for a certain amount of potential outward deflection in the event of an impact. The amount of deflection depends on the type of wall to be constructed. The downslope buffer zone must be designed and maintained as an open, empty space. The type of catchment structure has not been decided, and may vary from a flexible barrier to a more rigid design, so it is important that this buffer zone is a consideration during design stages. A flexible catchment fence will require more consideration of outward deformation than a rigid wall, and will require a conservatively sized buffer zone. The intent of flexible barriers is to slow the velocity and decrease the energy of the falling rock, not necessarily to stop it completely. Rigid barriers have the limitation of being prone to damage during high energy events, but this is generally the case with most constructed rockfall barriers. The barrier should be designed to withstand the types of energies predicted by CRSP analysis results described in this report. The catchment structure will require periodic and routine cleaning of the accumulation areas to remove debris. The rockfall remediation should be designed, constructed, and maintained to ensure hazards impacting adjacent or downslope properties are not aggravated. In its current condition, the western half of the site is impacted by rockfall consisting of boulders the size of 10 feet or more. These boulders have historically rolled and slid down the slope from the steep cliff faces exposed upslope from the site. The vegetative cover on the slope above the project site acts to slow rockfall events in its current condition. If this vegetative cover were to be removed for some reason (e.g. clear cutting, wildfire), these obstacles would be removed and the rockfall hazard would increase. 8.2 LANDSLIDE CONSIDERATIONS Cesare did not observe evidence of recent landslide movement at the project site. The retaining wall for the Town of Vail shuttle stop which is located at the toe of the landslide, appears to be performing adequately. The landslide area displays benched and hummocky topography with over - steepened toe and flank areas, however, fresh landslide features, such as tension cracks, scarps, slumps, and other features, were not observed. Figure 7 shows the bare earth land surface and provides a convincing depiction of the landslide extents. Cesare is not aware of landslide movement causing distress to the townhomes in the Pitkin Creek subdivision notched into the toe near the southeast corner of the site. Based on the lack of evidence of recent landslide movement as observed onsite and through aerial photographs and LiDAR imagery, Cesare does not recommend monitoring of the landslide at this time. Slope stability should be a primary consideration if ground modifications and development 17.5029 Rockfall Hazard Study, East Vail Parcel 06.19.17 29 CESARE, INC. are planned in or near the landslide mass. The landslide has the potential to destabilize if the ground is disturbed or modified in adverse ways. Slope stability of the over -steepened toe and flank areas, as well as large-scale global stability should be considered. In addition, the bedrock is dipping gently out -of -slope, exacerbating the slope instability issue. 8.3 DEBRIS FLOW CONSIDERATIONS Although the site is not within the limits of the Town of Vail Debris Flow Hazard zone, there exists the potential for debris flows at the site. Material and debris which could mobilized in a debris flow event cover the slopes at and above the site, including glacial till capping the ridge above, and rock talus and colluvium on the slope above the site. Incised drainages actively flowing with water are present on the west side of the site, and ground surface patterns visible in the LiDAR imagery suggest erosive processes are underway in this area. A significant precipitation event has the potential to trigger or increase the probability of a debris flow event, additionally, ground modifications may alter or increase this debris flow hazard in some areas. Cesare recommends the debris flow hazard potential be considered in future development stages. 9. LIMITATIONS This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geologic and geotechnical engineering practices. No warranties, either expressed or implied, are intended or made. 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Geotechnical Engineers & Construction Materials Consultants APPENDIX A Documents and Drawings Reviewed References CESARE, INC. DOCUMENTS REVIEWED DOC1. Chen and Associates, Inc., Soil and Foundation Investigation for Proposed Pitkin Creek Townhouses Near Interstate Highway 70, East Vail, Eagle County, Colorado, Project No. 17,046, dated September 20, 1978. DOC2. Chen and Associates, Inc., Geologic Hazards Reconnaissance, Lot 11, Block 1, Vail Village 12th Filing, Vail, Colorado, Project No. 25,474, dated January 26, 1983. DOC3. Colorado Geological Survey, Rockfall Hazard Assessment at Booth Falls Condominiums, and Proposed Mitigation, prepared for the Town of Vail, Colorado, undated. DOC4. Nicolas Lampiris, letter re: Unit #13, Pitkin Creek Townhomes, prepared for Nedbo Construction Company, dated September 12, 1987. DRAWINGS REVIEWED DWG1. Topographic Map of a Portion of the South 1/2 of the Southeast 1/4 of Section 2, Township 5 South, Range 80 West, Town of Vail, Eagle County, Colorado, prepared by Peak Land Consultants, Inc., dated January 10, 2017. REFERENCES REFI. Kellogg, K.S., Bryant, B., Redsteer, M.H., 2003, Geologic Map of the Vail East Quadrangle, Eagle County, Colorado: U.S. Geological Survey Miscellaneous Field Studies Map MF -2375, Version 1.1. REF2. Kellogg, K.S., Shroba, R.R., Premo, W.R., Bryant, B., 2011, Geologic Map of the Eastern Half of Vail 30' x 60' Quadrangle, Eagle, Summit, and Grand Counties, Colorado: U.S. Geological Survey Scientific Investigations Map 3170. 17.5029 Rockfall Hazard Study, East Vail Parcel Documents and Drawings Reviewed, References, Appendix A SARE, INC. Geotechnical Engineers & Construction Materials Consultants APPENDIX B Rockfall Hazard Assessment at Booth Falls Condominiums and Proposed Mitigation (Colorado Geological Survey) 1 w r j L 1 L J ROCKFALL HAZARD ASSESSMENT AT BOOTH FALLS CONDOMINIUMS AND PROPOSED MMGATION prepared for The Town of Vail, Colorado by Jonathan L. White Colorado Geological, Survey 1313 Sherman Street, Room 715 Denver, CO 80203 ph. (303) 894-2167 fax (303) 894-2174 1 1 1 1 1 1 1 1 1 A 1 1 1 1 1 1 1 1 i 0 *Booth Creek Rockfall Report, Page i CONTENTS Page Introduction 2 March 26,1997 Rockfall Event 2 Hazard Assessment 4 Rockfall Mitigation Options �} Rockfall Analysis and Design Criteria t� Recommendations 7 Current and Future Actions 8 Appendix A. Booth Creek Rockfall Hazard Area by Bruce K. Stover Appendix B. Rockfall Mitigation by Jonathan L. White List of Figures and Photos: Figure #1 Site map and location of March 26, 1997 rockfall. 3 Figure #2 Screen dump of CRSP slope profile 7 Photo #1 Booth Creek rockfall source area 4 Photo #2 Top Cliff rockfall source area S Photo #3 Close-up of top cliff source area S Photo #4 Location of proposed mitigation at Condos 8 Photo #5 Lower cliff above district to be monitored 9 ' 0 Booth Palls Roclfall Report, Page 2 INTRODUCTION The Colorado Geological Survey has assisted the Town of Vail in assessment of the rockfall hazard at Booth Creek since May 1983, when a severe rockfall event occurred there. Since then the town and property owners in Vail Village Filing 12 formed a Geologic Hazard Abatement District (GRAD). The District has mitigated much of the hazard by the construction of a ditch and berm on the slope above the residential area As far as the Survey knows, the ditch and berm configuration has been 100% effective for rocks that continually fall from the cliffs of the Minturn Formation. On March 26, 1997, another very serious, potentially lethal, rockfall occurred that incurred substantial damage to the Booth Falls Condominiums that exists to the west of the GHAD and outside the protection envelope provided by the ditch and berm. Under the auspices of the Critical Geologic Hazards Response Program and our concerns expressed in earlier involvement, the CGS can assist the Town of Vail in assessment of the hazard that the condominiums bear, options for mitigation for that portion of slope west of the ditch and berm terminus, and design criteria for said mitigation systems. Included in this report are two appendices. Appendix A, Booth Creek Rockfall Hazard Area by Bruce Stover, is a report on the general geology, geomorphology, and the mechanism of rockfall for the Booth Creek site. Appendix B, Rockfall Mitigation, is a short paper on types of rockfall mitigation systems that are available. THE MARCH 26, 1997 ROCKFALL EVENT At 11:20 p.m., a ledge of Minturn Formation limestone at the highest exposed outcrop of the upper cliff, just below the exposure of glacial till, failed similarly to that shown in Figure 3 of Appendix A. The ledge dimensions that detached and toppled is roughly. 20'x 8'x 8'. As it fell, it impacted and broke additional rock blocks from outcrops below. The rock mass broke apart as it tumbled down the clif. As it fell down the slope, the rock fragments randomly fanned out such that the path of the rockfall formed a swath more than 500 feet across where they came to rest. See Figure #1 of this report. The location of the rockfall source is shown by arrow in Photo # 1 and #2 and the scar easily seen in Photo #3. Approximately one third of the swath of rolling rocks were retained by the ditch and berm. See Figure #1. The remaining two-thirds of the event came to rest, scattered around the condominiums. The condo structures received three rock impacts and several near misses_ Rock sizes ranged from 2 to 5+ feet in average diameter. Surrounding the condos several items were also damaged or destroyed, (i.e., small haul trailer, trampoline frarne, small wooden deck and chairs, wood walkway). Of the three impacts, one was minor and the other two major. The minor impact was from a -3 foot diameter rock that obviously had slowed almost to a stop upon impacting the westernmost condo structure. The rock came to rest, ominously so, next to a large boulder from an earlier rockfall. A major impact, also about 34 feet in diameter at high velocity, had just missed the ditch and berm catchment. The rock impacted and smashed the comer of the easternmost condo, snapped off the side balcony support, and destroyed a trampoline frame along its path before coming to rest in the subdivision below. The third and worst impact was a 5+ foot block that broadsided the easternmost condo. Sufficient rock velocity enabled the boulder to smash through the outside wall, interior walls, and the floor, finally being caught in the crawlspace below. Luckily the resident, whose bedroom this rock smashed through, was not home at the time of the rockfall. Booth Creek Rockfall Hazard Area - Vail, Colorado Areal extent of rockfall impacts from 11:20 pm, 3/26/97 event. 6+a9. _ 3 447 I i I. ss�o,s X caurt e3•t.2 e3•o.e x , K 13 -My B17e8 I X P1JMK a e1".1 �.0 figure 41. I Booth Creek Rockfall Report, Paa Rockfall Source: Limestone bed at highest point of upper cliff. See companion photos in report. Location not shown on town GIS map. one inch = 200 feet `0 The berm was 100% effective for that 1 portion of the ;/26/97 event that fell into iL o337.G LO k x x . � � # ■tta 5�� x y 1113.5 i 4a= t lA � 0 Booth Falls Rockfall Report_ Page 4 The CGS made an initial inspection of the site Thursday, March 27, 1997. Our preliminary assessment was that it appeared that the ledge broke away relatively clean and the hazard risk in no greater or less than the day before the rockfall; which is to say that rockfall can occur from this source area anytime. It was on our preliminary inspection of the ditch and berm where we discovered that an earlier rockfall event occurred, either earlier this year or sometime after the town last cleaned the ditch out. Several rocks (s4 foot diameter) had fallen and, by lithology, could be differentiated from the March 26 event (sandstone vs. limestone). This rockfall occurred without anyone's knowledge because the entire event was contained within the ditch and berm. Friday, March 28, 1997 an aerial reconnaissance was conducted of the source area and while the preliminary assessment has not changed, we reiterate that rockfall of similar magnitude will continue at this site. During this inspection we did see several loose rocks on the slopes and rock features with questionable long-term stability. HAZARD ASSESSMENT In a ranking of a rockfall hazard the parameters are source area, a steep acceleration zone, proximity of structures to both, and history of rockfall impacts. In two aspects the condominium location is worse than most of the special district to the east because the upper cliff is more fully exposed at this location (it is mostly soil covered to the east) and the slope between and below the cliffs steepen where the slope curves around into Booth Creek Valley. See Photo #1 and Figure #1 map in Appendix A. ~-WE QW- . _.-.� � ,�, � -� • __ . - — The main source area for Booth Falls �''`'-' Condominiums is the upper _ cliff. The exposed, lower cliff of sandstone reduces in height as it trends to the northwest. Photo #1 and a close-up photo #2 show the x extent of the upper cliff f J /S - where it is not soil covered. They reveal a benchy cliff of beds of limestone, thin shales, = and minor sandstone. It is the -- - dense, hard, gray limestone that creates the largest rockfall boulders in the Booth Creek area. The report by B. Photo 41. Booth Creek rockfall source area. Note enlargement of upper cliff Stover in Appendix A exposure and corresponding rockfall source area, northwest of the ditch and provides further in-depth berm terminus. discussion on the source areas. Photos #1 and #2 also show the exposed shale slope, between the cliffs, steepening to the left. The general lack of soil and vegetation suggests that this slope is harder and smoother, compared with the right. A further close-up, Photo #3, reveals limestone blocks, pedestals, and ledges, defined by the crisscrossing joint pattern, being undermined by the quicker- 0 0 Booth Falls Rockfall Report, Page 5 eroding interbedded shale partings. Also in Photo 93 are several slumped and isolated limestone blocks on the rock slope that have not vet fallen. The history of reported rockfall events at Booth Creek and the physical nature of the slope merits our assessment that; Booth Falls Condominiums is in a severe rockfall hazardous area. Photo #2. Top cliff rockfall source area. White arrow marks location of March 26, 1997 rockfall. Photo 43. Close-up aerial view of source area. Note sedgy appearance with joint defined blocks undermined by erodin, shale partings. White arrow A marks scar from March 26. 1997 rockfall. White arrow B marks rock pedestal that was hit by rockfall and may be destabfized. Note loose blocks, marked by black arrows. Booth Falls Rockfall Report, Page 6 1 ROCKFALL MITIGATION OPTIONS Appendix B contains most of the recognized forms of rockfall mitigation and protection devices commonly used. Rockfall mitigation is divided into two types: stabilization of the rock mass at the source area to prevent rocks from falling; and rockfall protection systems that acknowledge that rocks will fall but structures or public areas are protected from the impacts. At the Booth Creek site stabilization of the rock mass at the source area is not being contemplated for several reasons. They include: 1. The source area is in the USFS Eagles Nest Wilderness Area; 2. Source area stabilization at this site would need to cover a large area, be labor intensive, require technical rock climbing skills, and helicopters for mobilization that would make the project cost prohibitively high; 3. Source area stabilization construction activity would present unacceptable risks that rock could be inadvertently knocked down, by workers or equipment, onto the residential areas. RockfallY rotection systems that will be considered at this site are ditch and berm P configurations and impact barrier wall systems. Fences will not be considered because they can have high maintenance cost and generally cannot withstand high impact forces without being destroyed. I ROCKFALL ANALYSIS and DESIGN CRITERIA Proper analysis of the hazard for design purposes requires accurate slope geometry and a determination of appropriate rockfall sizes. For the slope geometry we used information gained from our earlier investigation for the special district mitigation, the Town of Vail GIS 1:2400 scale maps, photos, and the USGS 1:24,000 scale map. For the rockfall size using the maximum size boulder that is found on site would be prudent. We used the Colorado Rockfall Simulation Program (CRSP) ver. 3.Oa for our analysis. Four to seven foot diameter boulders were modeled, and weight was calculated using the unit weight of limestone. The analysis seemed to bear out observable results of rockfall in the area. Bounce heights were highest on the cliffs and at the transition to the lower, softer slopes the rocks begin just to roll. The critical design factor is the high impact energies developed by these larger rocks. A screen dump is shown on Figure 42 of the CRSP program slope profile. An analysis point was chosen 30 feet upslope from the condominiums where the slope breaks to a grade of 40% to 50%. In modeling rockfall with CRSP we arrived at the following Ibounce heights, impact kinetic energies (K.E), and velocities at this analysis point. 11 Rock Rock Bounce K.E.(rnax) K.E.(avg.) Vel.(max.) Vel.(avg.) Size Weight ft. ft -lbs. _ ft -lbs ft/sec ft/sec 4' sphere 5058 3.0 1,000,000 800,000 98 83 5' sphere 6' sphere 9878 17069 2.1 2.0 1,900,000 3,000,000 1,400,000 2,300,000 95 96 81 78 T sphere 27106 1.7 4,600,000 3,300,000 89 74 4'x7' cyl. 13272 1.7 2,500,000 1,700,000 93 74 5'x6cyl. 17775 1.9 3,600,000 2,400,000 94 76 6'x6' cyl_ 25600 1.9 4,900,000 3,500,000 89 74 6'x7' cyl. 30000 1.8 5,700,000 3,700,000 90 72 11 Booth Falls Rockfall Report, Page 7 Figure 2. Screen dump of CRSP program of Booth Creek -west side. Analysis point arrow is 30 feet above condominiums. Horizontal and vertical are not at the same scale. RECOMMENDATIONS The following recommendations and design criteria are based on modeled rolling rocks analyzed at 30 feet upslope from the condominiums, so are only valid at that point on the slope. Mitigation design should not only insure that rockfall is contained but also the impact structure remains sound and does not require costly reconstruction afterwards. The CGS recommends that design criteria for mitigation at the condominiums should be capable to withstand and retain a worst case scenario, which is believed to be a boulder in the 6 to 7 foot diameter range. An examination of the source area, the most recent rockfall, and earlier research done by Stover and Cannon for work the CGS did in 1988 seems to confirm this scenario. That translates to a rolling rock with an impact force of 5,000,000 ft -16s at the analysis point. Besides withstanding the impact force the mitigation system would need to prevent any rock that encounters it from climbing and overtopping, or bouncing over. The impact face should be vertical and have an effective height that prevents overtopping. Design height will be specific to siting of the structure. At the analysis point it should be no less than 12. These design parameters do not take into account smaller rock fragments that separate from larger boulders. During inspection of the site following the March 26, 1997 event there was evidence of smaller rocks snapping off the tops of Aspen trees, 25 feet high, near the condos. These rock fragments do not reflect actual bounce heights but display the high rotational velocity of the rock and the centrifugal force acting on fragments as they detach. Options to mitigate these highly random rock fragments are limited to moving the protection system farther up the slope (which will change design criteria) or constructing a low capacity rockfall fence at the top of the berm or wall. Booth Palls Rockfall Report, Page 8 Only a stout protection _ system can be designed at the criteria stated above. Both ditch and berm systems and inertial impact barriers, ora combination of both, can be designed for the site and be cost - effective. No rockfall fence on the market can probably -` y; _ -its sitz x withstand the impact forces that are being contemplated. The rockfall protection must be designed to begin at the road and extend to the southeast to a # . point where sufficient overlap ~ exists with the existing berm - above, a length no less than 350 feet. Rocks that skirt the edge of the top berm must be caught Photo #4. Location of proposed impact barrier or berm site. Note by the lower. See Photo #4. At accumulation of rocks in existing ditch. The largest are 5 feet in diameter. the high impact velocities and corresponding impact forces both ditch and berm and reinforced impact walls will need to be carefully designed. In a ditch and berm option a careful look will be needed to determine whether the berm of only compacted soil will have the strength to withstand these forces. The earthen berm may need to be reinforced with geotextiles. A rockfall impact barrier or earth wall will need to be reinforced with geotextiles in lifts of 5-12 inches and have a width no less than 10 feet. We recommend that the Town of Vail retain the CGS for review of the mitigation design and our approval be a condition for design acceptance by the town. CURRENT AND FUTURE ACTIONS Adverse or highly variable weather prevented the CGS from doing a site inspection of the source area immediately after the March 26 event. Later this spring we plan to conduct this site inspection where the failure occurred and examine those impacted rock features below that may be of questionable stability. During our aerial inspection we also found a rock feature above the special district ditch and berm that may require long term monitoring. See Photo 45. While we believe this feature will not be a threat for many years it bears watching because of its size. If this feature were to fail the vol - me of the fall would quickly overwhelm the capacity of the ditch and overtop it. We will provide the Town of Vail a supplemental report based on our field studies later this summer. For the interim, residents of Booth Falls Condominiums who are concerned about their safety can take precautions to lessen their exposure to rockfall hazards. As stated the larger rocks are basically rolling when they reach the condos. The safest area in these condos presently is the top floor on the side facing downhill. The worst case rockfall impact can put a big hole through a 0 Booth Falls Rockfall Report, Pale 9 Photo #5. Lower sandstone cliff above district ditch and berm. The CGS will visit this feature this spring and install movement gauges for future monitoring. structure and possibly condemn it, but probably will not tear it down. Our advice to residents is that they not establish living areas where they spend the bulk of their time, such as bedrooms and the sitting areas of living rooms, against the exterior wall that faces upslope. Bedrooms should be moved upstairs and/or beds placed against the wall facing downhill. Do not place beds directly in front of, or below, windows that face uphill. The Home Owners Association and Town of Vail should act quickly so that these structures are protected from the next rockfall of similar magnitude. it 11 iI UI 1 • 1 Ll APPENDIX A 1 fl 1 1 i Boom CREEK RUCKFALL HAzARD AREA Bruce K. Stover Colorado Geological Survey, 1313 Sherman Street, Room 715, Denver, CO 80203 Residences situated atthebasc of thevalleywatl at themouth of Booth Geek in Vail Valley are exposed to varying degrees of rockfall hazard (Figure 1). The hazard ranges from low to moderate for structures near the limits of the runout zone on the valley floor, to very !sigh for some rrside.n= eoustxacted in the lower pad -of the aeceleradon zone at the base of the d*,- The arca vrAs developed prior to the time when Vail had adequate gcol4r, hazard mapping or zoning completed. The rmkfall _hazard was thus not identified prior to development. The problem was investigated in detail after a major rock:U even# izt May 1983, caused serious damage to several strucn=. in the years since the original hazard investigation was con- ducted, several more significant rockfall, events have occurred; boulders have destroyed timber patios and log retaining walls, dwzagcd W¢erior walls, and smashed completely through struc- tures causing considerable damage to interiors and fu mishings. - The town of Vail and affected property owners are current- lypursuing a means and framework for administering design and construction of protective rockfall structures and barriers in an attempt to safeguard the residential area. Geology of Rockfail Source Meas The geologic make-up of the diffs above Vail Village F -ding 12 is %%own diagrammatically in Figtue 2 Scdimcatary strata ex- posed in the r.liB[s are past of the Minturn Formation of Middlc Pennsylvanian age, and include beds of sandstone, shale, grit, conglvmcratc, and limestone. The beds strike N85�W and dip 15° to 18° into tLe vafley axis. The lawer cliff consists of shaley sandstone beds about 12 m thick resting on a weak, fissile, rapid- ly eroding black to gray shaie. 'Me sandstone unit has two prominent joint sets striking NMOW and N55°W. These joints combine to separate large slabs and dei`me the cliff face angle vistible from the valley below. Above the sandstone is a soft, fri- able coarse sandy conglomeratic bed 1 m thick which weathers to a smooth rounded ledge and continually undercuts a 0.6 to 1 m thick dense, hard gray limestone unit resting above it. The Emestoac is jointed so that subangular blocks (.5 x.6 x 1 m) con- tinuously detach from the bed and fall off the sloping diff edge. These limestone blocks are commonly involved in the more fre- quently recusing events that can often cause damage to struc- tures in the runout zone. A thick shale unit between the upper and lower cliffs has weathered back to a 68 percent slope- The shale is soft, clayey, and shows evidence of localized slippage and small slope failures which probably oxer duuing iutcnse rainstorms or heavy snow - =tit, Very small mudflows appear to start on this steep slope and spill over the km-cr ells` c€ m They are capable of disturb- ingor wditingrockbDsifboulders happ= to be in their paths, or are resting near points of initial failure. Above this soft eroding shale is a thicker cliff -forming unit of the Robinson Limestone- This bed of dense, hard, gray lime- stone varies from L5 to 10 in think in the study area and is the source for the largest rockfall boulders encountered in the runout zone. The limestone boulders that detach from the cliff are quite resistant and tend not to break up or shatter on their way downslope. The largest boulders found in the runout zone appear to be derived from this upper cliff -forming limestone. ne shala-zme upoo whirls the upper limestone CIM rest is weak and by erosion tmdercau the massive limestone lcdgc:&, creating pedestal -like blocks which eventually topple off their perches. The limestone is jointed such that blocks approximate- ly 3 m x 1.2 m x 12 m are separated from the cliff and tilt out- ward toward the cliff edge- Thinner beds within the limestone diff produce more slabby blocks that, if not turned onto their edges by chance during the initial fall, remain flat -side down on the steep slopes. An eroding slope in glacial till rests directly above the cliff - forming upper limestone in the northern part of the study area. The eroding slope periodically sheds smooth, rounded granitic boulders which tumble down the cliff into the runout zone. Other areas of this till farther east along the cliff appear relative- Figure 1. Location map of study area, scale, 1:7A,000 ly stable, and are not actively shedding large rocks to the slopes below. Ahave this tall, slopes flatten dramatically to Wades of 0 to 35 percent_ Large stands of maws aspen indicate that thmsc gentle upper till slopes arc relatively stable. No other rorkfall sources existaNwc these gentle slogs which start at an elevation of ap- proximately 9,450 ft. Physical Configuration ThcAoep southwest-facingslope and rocky cliff tower 1,000 ft (305 m) abWe Vail Voltage Filing 12 cm its northern boundary. These boots are attained within a horizontal distance of 1,700 h (520 m) resulting in an avm-ap slope of 58 percent. The slope can be divided unto several zones (Figure 2) A) Runout zone - slopes of 28 to 45 percent along the foot of the vat wall. This area is mcoerawy wooded with fairly youing aspen and has been developed as a residential subdivisiosi. Tice Wjority of rocks failing from the cliffs come to rest in this nano. B) Arcelerafion rope - slopes of 55 percaot to 65 per- ecnt and steeper immediately below source area. So boulders of significant size can remain at rest 08 tl m stapes due to the stcepocss. Sparse, stunted aspen occur in small stands, but gencrAly the slopes do not support much vegetation- Roves Vavcn ng thisportion of tbeslope wnll continue to gain momen- tum as they roll and skitter dowasloM C) Lower vertical diff snurce area - A 50 ft high (16 m) cWofjointed sandstone andlimestone mpouts 560 vortical ft (175 m) above the runout zone. Large slabs 15 to 20 ft (4-5 to 6 m) in diameter, periodically detach from the cliff face and tilt outwards mlil they topple over and shatter, showering boulders onto the acceleration -zone slopes below. (Figure 3) D) Upper shale -slope acceleration zone - A steep (68 punt) shale s]npo above the [owes vertical rdiff at - lows boulders from a higher miff to gain momnutum before becoming airborne at the stiff edge. E) Upper verticil cliff source arca - Jointed slabs and boulden 1,000 vertical ft (305 m) al}ow the runout zone periodically detach from the cliff and free fall and bound downslope and off the lower cli$ Most rocks do not shatter, but remain as intact ap- proximately 8 by 5 ft (2.5 by 1.5 m) limestone boulders which are capable of reaching the farthest Emits of the runout zone. (Figure 4) F) Eroding upper till slope - Glacial till resting on top of the upper cliff sheds rounded granitic boulders ' BODING GLACIAL TILL UPPER �:D'•O•• ! LNMESTONE CLIFF ROCKFALL SOURCE AREA LIPPfrA SHALE- A+CCFLERAT*N SLOPE LOWER SANDSTONE LEDGE f� f LOWER .. SAJNDSTONC CLIFFS ACCELERATION ZONE LOWER ERIMiTIGU =f f f SHALE REDS COLLUVIUM ON ACCELERATION � � SLOPES �fr— RUNOUT ZONE �RESIDENTIAL STRUCTURES BOULDERS IN RUNOUT ZONE a !r Figur 2. Geologic diagram of compound rock -fall slopes in study area. Drawn to scale with no vertical esmggastim Note dip of strata toward valley. downslope which roll and fall off the cliffs. This till slope is considered to be a part of the upper source area Roc]dall Mechanisms Several natural geologic and topographic facrors combine to cause roWa% from the cuffs exposed on the uonh valley wall of Gore Creek in the study area. These factors include joint pat- terns, differential weathering of various rock types, dip of strata, and the slope of cliffs and acceleration zones. Jointing and Differential Weathering of Cliff Faces joust patterns in the cliff forming rocks are canscd by stress relief and physical proputies of the rock. The joints so Formed defLue planar, vertical cliff faces and act to separate large scc- tiozYs of the cliff uuo slabs along joints subparallel t o I he cif$ face. Once a slab has detached from the sedimentary bed, it begins to creep outwards owing to gravity and frost wedging in the joints. The joints widen with time, and are often wedged farther apart by tree roots, and smaller rocks that fall into the cracks formed by the joints. (Figure 3) UacrentW vo,_- theringof shales has andcrcut the mom sis- tant averlying sandstones or limestones c mating a lsori=ntal gro= or averhang at the base of the diff which removes sup- port for the rocks above. Eventually, the overhanging ledge lie- aames incapable of supporting its own weight, and fills or top- ples from the Miff. If rhe overhanging slab tzar already detached Form the cW aloag Joints and is res* preratiousiyon the shale, txndcrcuxting and differential weanccr4 a k -Ac the Proms which fma y results in inevitable toppling of the slab. As the largeslabs topple ouzo the acceleration slopes below, they usual- ly shatter into many smaller boulder mrd chw*s whirl► ac- celerate downslope to the runout zone. The toppling may t4 - ger adjacent unstable parts of the cliff to fall as well. Dip of Strata and Topography The dip of the rock ledges making up the source area also contributes to rockfall along cliffs in the study area. The strata in the two cliffs dip approximately 15 degrees into the valley, causing any to= stones, cobbles, or boulders on the ledges to inevitably move down to the edge of the 16 in vertical cliff limestone bloclu separated from their beds by jointing and weathering creep down toward the valley along these dipping bedrock surfaces (Figure 5). Rounded glacial cobbles and gravel 1■ 2. �r 3. �+ —77Jt'7 la r.r ff a • Figura 3. Toppling SlalAaih re Segoenoe. L labial cliff eoaftarada& 2. Diaratial weathering of soft shale begins to undercut massive diff forming subs. Joints open and widen due to slope er'erp and frost wedging. Springs issue from contact beneath dllL 3. Undercutting continoes. joints widen and arewedged open by smaller rocks, musing slab to tilt outwards. 4. Slab falls from diff face onto aeon slopes, bringing down overlying rocks. S. Slab topples and shatters, showering runout zone below with boulders, and aposing new diff face to erosion. .f •�#.r8 t• wen � � t TLL Figure 4. Limestone slabs resting on weak shale pedestals, upper dict son= area. Figure 5. Slope creep causing limestone blocks to move down bedding planes and off lower cliff edgy Blocks are generally 2 it x 3 ft. This mechanism is responsible for frequent rock falls in the study area. jt • % w i + f • • Figura 3. Toppling SlalAaih re Segoenoe. L labial cliff eoaftarada& 2. Diaratial weathering of soft shale begins to undercut massive diff forming subs. Joints open and widen due to slope er'erp and frost wedging. Springs issue from contact beneath dllL 3. Undercutting continoes. joints widen and arewedged open by smaller rocks, musing slab to tilt outwards. 4. Slab falls from diff face onto aeon slopes, bringing down overlying rocks. S. Slab topples and shatters, showering runout zone below with boulders, and aposing new diff face to erosion. .f •�#.r8 t• wen � � t TLL Figure 4. Limestone slabs resting on weak shale pedestals, upper dict son= area. Figure 5. Slope creep causing limestone blocks to move down bedding planes and off lower cliff edgy Blocks are generally 2 it x 3 ft. This mechanism is responsible for frequent rock falls in the study area. 1 1 0 OLDER ROCKFALL BOULDER GRANITIC BOULDERS IN TILL SOIL PROFILE DEPRESSION IN SOIL PITTED WEATHERED SURFACE �r+ t � • TILL i FRESH ROCKFALL BOULDER NO DEPRESSION t ' _f ' r +i- • sa t } ;. . INCONSISTENT DISCOLORATIONS EDGES EXPOSM Figure 6. Physical Merences between rockfall and glacially deposited boulders In runout zone. Roddall boulders are all llnaestone or sandstone, while glacial boulders are mostly rounded granite or metamorphic 1lthologles. Note that soli exists below roddall boulders, while itis absent beneath glacial boulder& slough down along the dip slopes and eventually fall into open direction radiating fi om he point of initial fall. Thepattern or cracks formed by joints, wedging slabs farther apart. trajectory a given boulder could follow is so unpredictable that The glaciated valleys of Gore and Booth Creeks both possess it is impractical to delineate individual hazard zonas based on relatively fiat bottoms and steep near lyvertical sides. The dopes the physical eonditioas of various segments of the diff Faces. In are so steep that once a boulder or slab topples from the cliffs, the present situation, hazard zones are. more practically w1ated it usuallycannot come to rest until it reaches the lower footslopes to horizontal .de tance from the source areas, zones farther away of the valley wall. An examination of the runout zone shows that experiencing a smaller probability of being encompassed by a large boulders and slabs have travelled onto and across parts of given ewmt. This approach yields an apprommately radialscrics the valley floor due to the tremendous momentum they acquire of zonas radiating out from the source area; the more severe in the acceleration zone. hazat+ds are obviously dosest to the diffs. it should be pointed out, however, that any area within the cadent of the runout zonae Factors Tdgger* RoclMls is subject to some degree of rockfall hazard Most of the rockfalls reported in this area appear to be re- lated to alternating freeze -thaw conditions. Events have oc- curred at night in winter, spring, and fall, after warm days of melting -have introduced runoff into joints and fractures. Upon freezing, the ice expands in the cracks sufficiently to topple an unstable block. Some events have also occurred on the other side of the cycle, as sunshine thaws the frozen cliffs, releasing a precariously perched block or boulder. Hazard Classifreatlon and Zonation The rockfall hazard associated with geologic and topographic conditions and the proximity of dwellings as described above is considered to be severe. The majority of large boulders found among structures in the runout zone have fallen from the cliffs. Feld study indicates that the question is not, "Will significant rockfall occur?", but rather, "What is the recur- rence interval between significant rockfall events?". Acceleration slopes are so steep and smooth that rocks traversing them are free to deflect and skitter laterally in any Hazard Zone Delineation Varying degrees of rockfall hazard severity can be ap- proximated by examination of the nature and positions of boulders and slabs in the runout zone. Each large boulder was examined to determine several factors which was used to ap- proximate the extent of the runout zone, and estimate the time spans since each rockfall boulder came to rest. These factors are 1) Whether or not a boulder was of rockfall origin or Slay deposited. -t) Whether or not a rockfall boulder was resting andis- turbed in its original position or had been moved by human activities. 3 j The physical nature of undisturbed rockfall boulders with respect to basal contact, (resting on surface, em- bedded, partially covered, etc.) and lichen, moss, and weathering patterns on exposed surfaces. 4) The comparative size distributions of boulders within the runout zone. 0 Rockfall Versus Glacial Origin of Boulders In order to determine the extent of the rockfall runout zone, it is necessary to determine whether boulders encountered belowthe cliffs in Vail Village have fallen from one of the source areas and come to rest on the surface, or if theywere transported in and deposited by ice or outwasb durtug Pleistocene glacia- tions. This distinetiou can be made by comparing the character of boulders found embedded in undisturbed glacial deposits with the limestone and sandstone boulders derived from the cliffs (Figure 6). Glacially deposited boulders are mostly rounded to subrounded smooth granite or metamorphic rocks which are imbedded in the surroundingglacial deposits. The ex- posed surfaces of these boulders are almost totally covered with lichens and moss. The heavy lichen cover and other well developed surface rock weathering features such as pits and etched relief of individual mineral grains, suggest that these boulders have been in place for 20 to 40 thousand years. The gla- cially deposited cobbles aad boulders arc 85 to 94 percent graniticandmetamorphic rock types, and very few limestone nr sandstone cobblcss or bouldw can be found in the till. TU is due to the fact that the only source area where valley glaciers could senutr and iuwj poi ate Cemestonc blocks is a =now (rand of rock one mile upsib-cam from the rwwur zone. The extensive upper basin whieb spawned the glaciers is composed of Precambrian igneous and metamorphic lkhologies, which make-up the vast majority of the rock types encountered in Q deposits found in the roeVall runout scat. In coatiaS4 large boulders and slabs of rockfall origin are pular nr poorly rounded, rest directly on the ground surface, do not shove an equal amount of weathering on all exposed surfaces, and are al- most mdtLsively limestone or sandstone. A few granitic rockfall boulders are also preserst, and arc derived From 0 in the upper S ource area. These differences were used to map the laca6om of large boulders of rockfall origin and determine the ap- proximate limits of the runout zone. Disturbed Versos Undisturkd Rocldall Booldm tJnrc a spc6fic boulder was idrati6ed as being of probable rockfall onoits position On the foot slopes could be used to predict the nature and extent of the runout zone. A problem with using the positions of rocltfall boulders in the subdivision and adjaama areas to delineate the runout zone is that many have been disturbed and moved from their original positions during development and ctia&uction activities Many of the bouddcn are too large (some weighing up to 15 res) to be maved easily, even by heavyequipment, and itis assumed thatthey,}tre moved only a few feet to several teas of feet from their original position in order to carry out construction of roads and building founda- tions. The accuracy of this assumption is not easily determined, and Lbc present positions of the disturbrd boulders as izidicatm of rusrsout zone and hazard zone rhanicteris ics are not endrety reliable. Disturbed or transported roddail boulders always show fres gouges arid abrasions caused by heavy earth moving equipment, Additionally, the• and lichen growth patterns, if any, are in- consistent with the present orientations of the boulders, indicat- ing that they have been moved after the patterns were estab- 1 hc4 Discoloration of the disturbed boulders c=etl by soil wntact can be observed on the sides or top of those which bane been pushed over and moved. Tlue boulders often leave trails or marks where thcy have been pushed along the ground, creating a small berm of scraped up sail along one of their basal edges. Undisturbed rockfall boulders do not show fresh gouges or scrapes, have consistent lichen and moss growth patterns, do not show soil discoloration on their sides or tops, and are often sur- rounded by young bushes, aspen trees, or natural vegetation, which has obviously not beteg disturbed. 71m positions of Ihrse boWders can be used to afore amtrately project the minimum limits of the runout zoom since they can be inferred to have none to rest in their present positioas after faIIing Ecom the cliffs. Factors Used m Approximate Age and Recurrenct Intervals W of Major Rockfall Events Certain characteristics exhibited by undisturbed rockfall , boulders and slabs in the runout zone, suggest approximate or relative time spans since they ease to rest after fatter ; and give a rough estimate of the recur=ce =ervals between large s3ab- failure events. The contact made by a boulder with the surfnce suggests how long the rock has feces resting in its present posi- tion As the length of time increases, thr, rock will tend to press into the ground, and slope wash, soil creep, and frost wedging will act to fill in around the base of the rock with soil materials. Rocks which have been si g for long periods tend to be some- what embedded in the soil, and if moved, would reveal an inden- tarion in the ground. Docks which have reccatty fallen rest directly on tlse ground surface, and may lie an brush or small trees they have aushed beneath them. one can push a stick beneath the edges of such a rock im some places. Older rocks also have more consistent lichen growth patterns than recently moved rocks which have detached from the cliff. Recentlymoved rocks may possess differentially weathered sur- as a result of their former positions on the kith If the btrulder acquired a surfer vmatharing and cruor pattern while on Lhc Jiffs, it is unlikely to roll to a stop in the same pasitint] and the surfaces whicli. were previously against the ground or fates joints may still possess a characteristic coloration o-a- trastirug with older, expLwd weathered surfaces. Considerable titne isneaessaryfor natural wcathcriug processes to remove- discoloration emovediscoloration and create a new uniform surface color on the rock. I Distribution of Roeldall Events Examination of the source area and runout zone revealsthat two basic types of rockfall events take place in the study area. The first and most common involves smaller individual boulders generally in the (03 x 1 m) size range, which detach front sedimentary beds and eventu-}ily fall from the cliffs. These f commonly involve several boulders, many of which are set in mo- tion after being struck by the initial falling rock This type 01 minor rockfall is common, and based on examination of the runout zone and cliffs above, can be expected to occur every one to three years. This is the type of rockfall which occurred in the rgpDaed events of May 1983, January 1986, and September 1987, damaging several structures. Many rockfall events go un- reported unless significant damage to structures occurs. The second type of rockfall is much less frequent, but of far greater danger and destructive potential. It involves massive slab failures of the cliff faces, along joints which liberate large (4S x 6 m) slabs and (2S x L5 m) limestone boulders, showering them onto the acceleration slopes below. The next rockfall of this mag- nitude will almost certainly result in extensive damage or destruction to structures in the runout zone below. An imprecise preliminary estimate of recurrence intervals for these large slab -failure events, based on examination of the source area and undisturbed rockfall boulders in the runout zone, is on the order of 40 to 100 years. Large boulders set in motion during these events can travel through the runout zone as far as the maximum probable limit. An estimate of the last oc- currence of this type of event, based on the freshest, undisturbed rockfall boulder in the runout zone, and weathering patterns on the cliffs, is on the order of 40 to 60 years ago. Potential Solutions to Roddall Hazards The feasibility of protective structures and other preventive measures were evaluated during the study. Smaller boulders commonly falling off the lower cliff could probably be arrested by protective structures built near the lower acceleration zone on property within the platted sub- division. The structures must be capable of absorbing the ener- gies of one ton boulders traveling at 50 mph, and would probab- ly involve energy absorbing materials held within timber or rock cribbing. Maintenance of the structures would benecessary each time a boulder is stopped, since the energy dissipation will damage or deform that part of the structure involved It is probably not feasible to build an armoring wall or other type of structure which attempts to arrest the boulders through rigid strength, due to the e:ttremely high momentum rocks gain through the acceleration zone. The unpredictable paths and pat- terns atterns followed by rocks skittering down slope makes it difficult 0 to determine the best places to site the protective structures. One approach would be to construct individual protective struc- tures for each building within the runout zone. Alternatively, a single large structure above the subdivision might provide as much protection and create less overall disturbance to the area. The structure would have to be carefully designed and con- structed to be free draining and to prevent adverse snow or ice accumulations from forming above the protective barrier. Siting a community type protective structure appears to be feasible if based on the detailed siting studies which would be necessary to determine the most suitable location. In either case, costs for these structures are estimated to be on the order of 0.75 to one million dollars, and could be higher. Unfortunately, these struc- tures would do little to prevent larger boulders or slabs derived through toppling failures from destroying structures in the runout zone. The energies possessed by such slabs or boulders are simply too great to contain within the restricted space avail- able between the source areas and existing residences. REFERENCES Mears, A.I., 1979, Colorado snow -avalanche area studies and guidelines for avalanche -hazard planning: Colorado Geological Survey Special Publication 7,124 p. Robinson, C.S., and Associates, Geological Consultants, 1975, Geologic hazard maps for environmental and land -use plan- n_n& Eagle County, Colorado. Rogers, W.P., et al., LW4, Guidelines and criteria for Wentifi- cation and land -use controls of geologic hazard and mineral resource areas: Colorado Geological Survey Special Publication 6,146 p. Shelton, D.C., 1974, Rockfall: variables which determine the hazard Unpublished report, Colorado Geological Survey Geologic hazard files, Denver, Colorado. Tweto, Ogden, and Lovering. TS, 1977, Geology of the Min turn 15 -minute Ouadrangle, Eagle and Summit Counties, Colorado: U.S. Geological Survey Professional Paper 956, 96 p. 1 1 1 �I F�l I APPENDIX B 1 C 1 1 t ROCSFALL MITIGATICO Jonathan L. White Colorado Geological Survey I TRODUC17ION Rockfall is a geologic hazard that is catastrophic in nature. For the most part it is viewed as a nui- sance by highway maintenance personnel who are required to clean the debris off the roadway and periodically clean out the fallen rocks with- in the roadside ditches. When rockfall occurs in populated areas or areas frequented by people, lethal accidents can occur. In general, rockfall occurs where there is . source of rock and a slope. Within the rock mass, discontinuities (bedding planes, joints, fractures, etc.) are locations where rock is prone to move, and ultimately, fail. Depending on the spatial orientation of these planes of weakness, failures occur when the driving forces, those forces that cause movement, exceed the resisting forces. The slope must have a gradient steep enough that rocks, once detached from bedrock, can move and accelerate down the slope by slid- ing, falling, rolling, and/or bouncing. Where the frequency of natural rockfall events are consid- ered unacceptable for an area of proposed or current use, and avoidance is not an option, there are techniques of mitigation that are avail- able to either reduce rockfall rates and prevent rocks from falling, or to protect structures or areas of use from the threat. There have been important technological advancements in rockfall analysis and mitigation techniques in the last several years. They include rockfall simulation software, rock mechanics software, and research and develop- ment in new, innovative mitigation techniques. This paper emphasizes mitigation techniques. There are, many factors that influence a selection and design of a mitigation system to reduce or eliminate a rockfall hazard. They include: 1. The rock source (lithoiogy, strength, struc- ture, and weatherability) and expected re- sultant fallen rock geometry (size and shape); 2. Slope geometry (topography); 3. Slope material characteristics (slope surface roughness, softness, whether vegetated or barren); 4. Proximity of the structure requiring protec- tion to source area and rockfall nm -out zone; 5. Level of required rockfall protection (the acceptable degree of risk); 6. Cost of the various mitigation options (con- struction, project management, and design); 7. Constructability (mobilization difficulties, equipment access, and other constraints); S. Future maintenance costs. For any public or private land use proposal, in steep sloping areas, the geologic hazard investigation should initially recognize those physical factors listed above. If rockfall has been identified as a hazard then a detailed rock - fall hazard analysis is warranted. The conclusion of such analyses, in addition to the detenrnina- tion of the factors above, must include: 1. An accurate determination of anticipated risk and frequency of rockfall at the loca- tion of the proposed land use, and; 2. Site specific calculations of the velocities, bounding heights, and impact forces for the range of anticipated rockfall events. Once all physical characteristics and calcu- lated falling rock dynamics are determined then the appropriate engineering and design can be completed for mitigation of the rockfall threat- ROCKFALL NUTIGATION TECHNIQUES The available techniques in effective prevention and mitigation of rockfall, fall into two cate- gories. One is stabilization of the rock mass at the source to prevent or reduce rockfall occur- rences. The other is the acceptance that haz- ardous rockfall will occur, but with the place- ment of protective devices to shield structures, or public areas, from the threat of impact. There is a third category that, while not a form of miti- gation, is a method that can diminish the cata- strophic nature of rockfall. It is rockfall warning and instrumentation systems. Systems, electrical and mechanical, that either will indicate that a rockfall event is imminent, or has just occurred. 0 Stabilization and Reinforcement Techniques that require in-situ or surficial treat- ments of the slope to induce additional stability to the exposed rock mass are termed rock and/or slope stabilization and reinforcement. Stabiliza- tion can be accomplished by any combination of the following: removing unstable rock features, reducing the driving forces that contribute to instability and ultimate failure, and/or increasing the resisting forces (friction or shear strength). 1. Scaling (hand scaling, mechanical scal- ing, and trim blasting). Scaling is the removal of loose and potentially unstable rock from a slope. On slopes of poor rock conditions scaling is generally viewed as a continual maintenance procedure because the loose rock removed exposes the rock underneath to further weathering. 2. Reduce slope grade. Laying a slope back can prevent rocks from falling from a source area. 3. Dewater or drain rock slope to reduce water pore pressures. The installation of drainage holes in rock can reduce the pore pressure in rock fractures—one of the dri- ving forces mentioned above. 4. Rock dowels. Rock dowels are steel rods that are grouted in holes drilled in rock, generally across a joint or fracture in the rock of unfavorable orientation. It is a pas- sive system in which loading or stressing of Figure 1. Rockbolts and dowels. 40 the dowel occurs only if the rock moves (slides) along the joint plane. (See Figure 1.) 5. Rockbolts. Rockbolts are installed much like dowels but are usually loaded or stressed, which imparts a compressive force on the rock. The loading of the steel rod during the installation increases the shear strength of the joint or fracture and pre- vents movement, reinforcing the exposed rock mass. There are wide varieties of rock - bolts, including mechanical, grouted, and binary epoxy resin systems. 6. Steel strapping. Steel strapping, also called mine strapping, is a strip of steel that bridges between offset rockbolts or dowels to support the rock mass between them. 7. Anchored wire mesh or cable nets. Fence wire or, depending on loading criteria, cable nets are draped on a rock slope and anchored to the rock mass by the bearing plates of rock dowels or rock bolts. The anchor pattern is set so that the wire mesh or cable nets are,in continuous contact with the rock face so that there is complete con- finement of the loose rock material. (See Figure 2.) ms Figure 1. Rockbolts and dowels. 40 the dowel occurs only if the rock moves (slides) along the joint plane. (See Figure 1.) 5. Rockbolts. Rockbolts are installed much like dowels but are usually loaded or stressed, which imparts a compressive force on the rock. The loading of the steel rod during the installation increases the shear strength of the joint or fracture and pre- vents movement, reinforcing the exposed rock mass. There are wide varieties of rock - bolts, including mechanical, grouted, and binary epoxy resin systems. 6. Steel strapping. Steel strapping, also called mine strapping, is a strip of steel that bridges between offset rockbolts or dowels to support the rock mass between them. 7. Anchored wire mesh or cable nets. Fence wire or, depending on loading criteria, cable nets are draped on a rock slope and anchored to the rock mass by the bearing plates of rock dowels or rock bolts. The anchor pattern is set so that the wire mesh or cable nets are,in continuous contact with the rock face so that there is complete con- finement of the loose rock material. (See Figure 2.) 1 • i 1 11 1 1 1 t 1 1 1 8. Shotcrete. Shotcrete is the sprayed applica- tion by compressed air of concrete on rock or rocky soil slopes for reinforcement and containment. Shotcrete applications can be strengthened by the addition of nylon or steel fibers to the concrete mixture, or the placement of a wire grid on the rock slope prior to application. Weep holes are usually drilled into the shotcrete to ensure that the contained material is free draining. (See Figure 3.) Figure 3. Shotcrete. 9. Buttresses. Buttresses are used where over- hanging or undermined rock features become potentially unstable and require passive restraint. Buttresses can be con- structed from many types of material. For concrete buttresses, rock dowels are gener- ally installed into surrounding competent rock to anchor the buttress in place. (See Figure 4.) IO.Cable lashings. Cable lashing is the wrap- ping of high capacity cables around a potentially unstable rock feature. The cables are then attached to anchors (rock dowels) installed in adjacent competent rock. (See Figure 5.) 11.Ground Anchors. Ground anchors are generally used to prevent large, potential landslide -type failures in heavily weathered, fractured rock and rocky soils. Their installation requires the drilling of deep holes and the grouting of thick bundles of high-strength wire strand, which are attached to large load-bearing panels and then stressed (pulled) to a desired tensional load and locked off. I 1"f 1 Figure 4. Anchored concrete buttress. Figure 5. Cable lashing. Rockfall Protection Devices When stabilization of rock slopes is not practical and sufficient room exists, protective devices or structures can be constructed to shield areas from rockfall impact. 1. Fences. Rockfall fences come in a variety of styles and capacities. They tend to become less effective and are damaged if not destroyed by larger rockfall events. (See Figure 6.) SOURCE AXEAr nvs.7car Figure 6. Rockfall fence. 2. Ditches. Ditches excavated into slopes can provide excellent rockfall protection. Care is needed in analysis and design to insure that bounding rocks cannot span the ditch width. (See Figure 7.) 3. Impact barriers and wails. Impact barrier and walls can be made from many types of material, from fill mechanically stabilized by geotextiles, rock gabion baskets, timber, steel, concrete, or even haybales. Highway departments commonly use Jersey barriers on roadsides to contain smaller falling rock in the ditch. The inertial systems, able to absorb the forces of momentum of the mov- ing rock, have higher capacities, without costly impact damage, compared to more rigid systems. (See Figure 8.) 4. Earthen berms. Berms are elongated mounds of fill, commonly used in associa- tion with ditches to increase the effective height and catchment of the protection device. (See Figure 7.) 5. Hanging fences, nets, and other attenua- tion devices. In well-defined rockfall chutes in steeper rock slope areas it is possible to anchor cables to span the chute and hang fence mesh, cable netting, or rock attenua- tion elements. Rocks that roll and bounce down the chute impact these devices, which attenuates (reduces) the rock velocity. (See Figure 9.) F � t Figure S. Mechanically stabilized backfill barrier. r Figure 7. Rockfall ditch and berm. U 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Figure 9. Tire impact attenuator. 6. Draped mesh or netting. Draped mesh is similar to the stabilization technique anchored mesh but is only attached to the rock slope at the top. Rocks from the slope are still able to fail but the mesh drape keeps the rock fragment next to the slope where they safely "dribble" out below to a catch- r---nt ditch or accumulate as small detrital fans. (See Figure 10.) Figure 10. Draped mesh. ' 7. Rock sheds and tunnels. Rock sheds and tunnels are mentioned here only because they are used mostly for transportation coni - dors. They have little or no application in most types of land use. AVOIDANCE - THE 100 PERCENT SOLUTION There is one more mitigation method that is nei- ther a stabilization/reinforcement system nor pro- tection system. It is strongly recommended at locations where rockfall hazards are very severe, and/or risks very high. Mitigation designs pro- posed in such areas may not afford the necessary level of protection. Bear in mind that no rockfall mitigation is 100 percent guaranteed, even in mild rockfall hazard zones. Avoidance is excel- lent mitigation and must be considered where cir- cumstances warrant. Any professional in rockfall analysis and mitigation (as with any geologic hazard) must, at times, inform developers, plan- ners, and the public that a proposed land use is incompatible with the site conditions. SUGGESTED READING Federal Highway Administration, 1989, Rock slopes: design, excavation, and stabilization: Publication FHWA-TS-89-045, prepared by Golder and Associates, Seattle, Washington, funded by the Federal Highway Adminis- tration, U.S. Department of Transportation: McLean, Virginia, Research, Development, and Technology, Turner-Fairbank Highway Research Center, [373] p. Federal Highway Administration, 1994, Rockfall hazard mitigation methods, participant work- book: Publication FHWA-SA-93-085, pre- pared for the Federal Highway Administra- tion, U.S. Department of Transportation Publication by SNI International Resources, Inc.: Washington, D.C., National Highway Institute (NHI Course 13219), [357] p. Hambley, D.F., ed., 1991, Association of Engineering Geologists, 34th annual meet- ing, Chicago, Illinois, Sept. 29—Oct. 4, 1991, Proceedings, national symposium, highway and railroad slope maintenance: Association of Engineering Geologists, 180 p. Hoek, Evert, and Bray, John, 1981, Rock slope engineering, (rev. 3rd ed.): London, U.K., The Institution of Mining and Metallurgy, 358 p. Pfeiffer, T.J., et al., 1995, Colorado rockfall simu- lation program, version 3.0a: Colorado Department of Transportation Publication CDOT DTD-ED3-CSM-89-2B. Available from: Colorado Geological Survey Miscell- aneous Information Series 39, diskette, 60 p. 10 0 COLORADO GEOLOGICAL SURVEY Division of Minerals and Geology Department of Natural Resources 1313 Sherman Street, Room 715 Denver, Colorado 80203 Phone: (303) 866-2611 FAX: (303) 866-2461 March 12, 2002 Mr. Russell Forrest Senior Environmental Planner Town of Vail 75 South Frontage Road Vail, CO 81657 STATE OF COLORADO - S14-18-0004 RE: Review of Rockfall Mitigation for Booth Falls Condominiums. Dear Russ: Oki DEPARTMENT OF NATURAL RESOURCES B i Il Owens Governor Greg E. Walcher Executive Director Michael B. Long Division Director Vicki Cowart State Geologist and Director The CGS was requested by you to provide some additional comments on the completed rockfall mitigation at the Booth Creek Condominiums in the Town of Vail. At your earlier request, I inspected the rockfall mitigation structures on October 22, 2001 after construction was completed last fall and sent comments to you in a letter dated November 9, 2001. A question arose concerning any potential impacts to adjacent owners from the construction of the inertial barrier walls designed for rockfall impact. During my site inspection last fall I did not note any way in which these structures would adversely impact adjacent owners, except for a remote possibility to the access road to the Town water tank. There should be sufficient room to stockpile the snow against the foot of the western wall if the water tank road needs plowing for access during the winter. Also the issue of maintenance and inspection of the structures was raised. The mechanically stabilized earth impact walls are basically maintenance -free. One concern I raised last fall was potential for sloughing or slumping of soil into the catchment zone from the bare cut slopes. If not cleaned out, the soil accumulation could effectively reduce the wall height. The cut slopes behind the walls (re -vegetated and stabilized as recommended) should be inspected every spring or after an unusually heavy precipitation event. The barrier walls should also be inspected after any rockfall impacts. Crushed portions of the wall facing after impact should be quickly repaired. Yenter Companies can provide guidance on recommended repair techniques for the wall facing. The only other type of failure of the system that could arise is a bearing failure of the native soils that the impact barrier wall is founded on. If tilting or sagging of portions of the walls is observed, the homeowner's association should inform Yenter Companies and require their staff to inspect the structure. Slight undulations along the length of the walls by differential settlement will not effect the performance of the structures. While an unlikely scenario, adverse tilting of the structures could be more problematic. Inspection of the walls and catchment zone behind should be part of a normal maintenance item of the condominium grounds by the homeowners association. I do not believe this action needs to be conducted by city staff unless distress of the wall parallel to the water tank access road is observed, which could possibly affect the roadway. Again, I believe it is very unlikely that this would occur. Enclosed with this letter is a copy of the original rockfall assessment report the CGS prepared after the March 26, 1997 rockfall event. If you have any questions, please contact this office at (303) 866-3551 or e-mail: jonathan.whiteQstate.co.us Sincerely, Jonathan L. White Engineering Geologist Western Ecosystems, Inc. EcotogicaCConsuttants goy West Coach Road, Boulder, Colorado 80302 August 10, 2017 Dominic F. Mauriello Mauriello Planning Group, LLC PO Box 4777 2205 Eagle Ranch Road Eagle, Colorado 81631 (303) 442-6144 email transmittal to dominic@mp".com Re: Rezoning wildlife assessment of Vail Resort's East Vail Workforce Housing parcel, Town of Vail. Dear Dominic, Vail Resorts owns the ± 23.3 -acre East Vail Workforce Housing parcel and is interested in the preliminary planning step of rezoning it for future residential development on a portion of the parcel. Wildlife issues will be a concern in the Town approval process. At your request, this document considers the more important wildlife issues associated with the parcel. A site visit specifically for this project was conducted on August 4, 2017 and I am familiar with the habitats present and the general wildlife issues from working on projects in the valley dating back to 1977. 1.0 LOCATION Figure 1 is an October 9, 2015 Google Earth image showing the parcel's location between Pitkin Creek, on the east, and Booth Creek, on the west. The parcel is located contiguous to the north of I -70's East Vail interchange whose 24/7/365 traffic influences the effectiveness' of the parcel's wildlife habitat. The Pitkin Creek townhomes are partly surrounded by the southeast portion of the parcel. Booth Creek residential development and school are located below Booth Creek Cliffs and the Booth Falls rockfall mitigation berm. The western end of East Vail occurs on the opposite side of the interstate. Because the image was taken in October, after leaf fall, the aspen -dominated hillside on the parcel is not apparent. 2.0 POTENTIAL DEVELOPMENT At this time it is unknown where and how much development could occur on the parcel. Steep slopes and rockfall hazard are two significant considerations. However, to evaluate the significance of wildlife issues, preliminary results of an analysis prepared by Mauriello Planning Group utilizing Town of Vail GIS mapping were considered. Mauriello Planning Group (2017) identified a 5.4 -acre area (25% of the entire parcel) in the far western portion of the property as the most likely developable area. Habitat effectiveness is the ability of animals to use a certain area of habitat compared to its maximum possible use. 3.0 HABITATS PRESENT The south -facing parcel is dominated by relatively young, pole -stage aspen with a mountain shrub understory. Figures 2 and 3 show habitat on the east and west sides of the property, respectively. t F JOf ` r t � Figure 2. View northeast of the East Vail parcel from the east -bound lane of I-70 across the widest (south -north) part of the parcel just west of the Pitkin Creek townhomes (western -most townhome at right). September, 2015 ground -level Google Earth image. 2 4.0 KEY WILDLIFE ISSUES The Town and Colorado Parks and Wildlife (CPW), may have several wildlife concerns associated with future development and habitation of residences on the subject parcel, however the current proposal to rezone the property would have no effect on wildlife. Engagement with CPW, as an advisory agency, should occur with any development application that is submitted in the future and considered in a more extensive Environmental Impact Report, as defined by the Town Code. These issues are discussed below, based, in part, on current (November 21, 2016) seasonal range files downloaded from the CPW website. The mapping is part of CPW's database, which provides information on wildlife distributions to public and private agencies and individuals, for environmental assessment, proprietary land management resource planning, and general scientific reference. The disclaimer associated with all CPW mapping is footnoted.z Polygons are defined by the observations of animal distributions over many years. 4.1 Bighorn Sheep Figure 4 shows six bighorn sheep seasonal ranges mapped by CPW in the vicinity of the East Vail parcel. Bighorn sheep winter range and severe winter range cover the same area and overlap most (± 2 NDIS [CPW kmz] mapping was derived from field personnel and is updated periodically [currently every 5 years]. A variety of data capture techniques were used including drawing on mylar overlays at 1:50,000 scale USGS county mapsheets and implementation of the SmartBoard Interactive Whiteboard using stand-up, real-time digitizing at various scales. Information depicted on NDIS maps is for reference purposes only and is compiled from best available sources. Reasonable efforts have been made to ensure the accuracy of this data. Colorado Parks and Wildlife expressly disclaims responsibility for damages or liability that may arise from the use of this data. The wildlife distribution maps are products and property of CPW, a division of the Colorado Department of Natural Resources. Care should be taken in interpreting these data. Written documents may accompany these maps and should be referenced. The information portrayed on these maps should not replace field studies necessary for more localized planning efforts. The data are gathered at a variety of scales; discrepancies may become apparent at larger scales. The areas portrayed are graphic representations of phenomena that are difficult to reduce to two dimensions. Animal distributions are fluid; animal populations and their habitats are dynamic. 3 75%) of the parcel. Winter range is that part of the overall range where 90% of the individuals are located during the average five winters out of ten, from the first heavy snowfall to spring green -up. Severe winter range (SWR) is that part of the winter range where 90% of the individual animals are located when the annual snowpack is at its maximum and/or temperatures are at a minimum in the two worst winters out of ten. The amounts, quality, and effectiveness of winter range are generally what limit big game populations. The polygon boundary is not accurate. It likely extends southeast to the treeline along Pitkin Creek, down to the interchange on/off ramps, and down to the north side of the frontage road. There is no I-70 game fencing in the area. Sheep likely used the habitat in what is now the Booth Creek residential area and it is unlikely that they continue to enter that development. The winter range and SWR overlapping the entire subject parcel is approximately 1.2% of the overall winter range and SWR polygons (approx. 1,880 ac.) that extends west along the north side of I-70 nearly to I - 70's Vail exit. This is the only sheep winter range polygon mapped on either side of the Gore Range. High concentrations of winter sheep pellets were located along the top of the Booth Falls rockfall mitigation berm during the site visit. Two homes located 107-177 feet below the berm give some indication of residential compatibility with sheep winter range. Winter concentration area is a subset of the winter range where animal densities are at least 200% greater than the surrounding winter range density during the same period used to define the winter range, in the average five winters out of ten. That polygon does not overlap the East Vail parcel, but habitat effectiveness of that polygon could be influenced by residential development and habitation on the parcel. .19 Bighorn sheep production area is where sheep lamb. Production areas are defined as that part of the overall range occupied by pregnant females during a specific time period in the spring (May 1 to June 30). The polygon occurs above the Booth Creek cliffs, extends 1.6 miles to the north, and is topographically buffered from residential development below. Based on ewes selecting cliff -like terrain inaccessible to terrestrial predators, it is unlikely that any of the forested terrain shown in Figure 4 is actually used for lambing. The effectiveness of production areas could be affected by free -ranging dogs and recreation originating from residences below. Bighorn sheep migration pattern is a subjective indication of the general direction taken by migratory ungulate herds. The line's location is irrelevant. What it indicates is that bighorns move downhill in this area during fall towards their winter range, then move uphill in spring to their summer range. A bighorn mineral lick is defined as a natural site known to be utilized by bighorn sheep for obtaining minerals to meet basic nutritional needs. Whether natural or otherwise, such licks are particularly important for pregnant and lactating ewes. Potential residential development on the subject parcel will be of concern because of the net loss of winter habitat (±0.24% of the overall winter range polygon) associated with residential development, further impaired effectiveness of habitat within the influence of the development, and other potential habitation -related effects (e.g., free -ranging dogs and dispersed recreation originating from residences). However, sheep habitat use in this area has adapted and habituated somewhat to I-70 and frontage road activity, Booth Creek neighborhood and The Falls at Vail townhome residential developments and activities, Vail Mountain School, and dispersed recreational activity along the Pitkin Creek and Booth Creek trails. The relatively small (5.4 -acre) potential East Vail development would result in a further loss of winter range, but its location in an area whose habitat effectiveness has been reduced by existing human disturbance and development should have minimal effects on sheep habitat use and should not affect herd size. Approximately 75% of the parcel would remain available for continued sheep use on a preserved and protected tract associated with the proposed rezoning and platting of the parcel. 4.2 Elk Figure 5 shows one elk seasonal range mapped by CPW in the vicinity of the East Vail parcel that warrants consideration. The elk winter range definition follows that provided for sheep, above. No elk winter range is shown overlapping the subject parcel, but that mapping is likely wrong. The winter range polygon boundary along the north side of I-70 appears to follow an assumed land ownership boundary. At the time of CPW mapping the County's and the Town's mapping assumed this parcel was likely in CDOT ownership. Colorado Parks and Wildlife appears to have adopted the Town's position and extended the polygon along the U.S. Forest Service property line, rather than bringing it down to the north edge of the frontage road where it probably should be. The elk winter range on the subject parcel is part of a polygon containing the highest elevation elk winter range in the Gore Creek Valley and some of the highest winter range in the Eagle Valley. This higher elevation winter range is used more during the early part of winters and during milder winters when excessive snow depths have not yet pushed animals to lower elevations down valley. Nevertheless, these winter ranges are valuable because they support animals during portions of the winter when animals would otherwise be further down valley on increasingly small and more crowded winter range. 3 A learned behavioral change exhibited by greater tolerance of, and reduced avoidance to, benign human activities as a result of chronic exposure. The extent of habituation is generally reduced in hunted herds. Over the past 50 years there has been a considerable loss of big game winter range to secondary ski area development in the Eagle Valley. Winter ranges generally occur at lower elevations along valley bottoms that are dominated by private lands. Development of those lands has pushed elk further west down valley. In recent years, CPW have increased their hunting permits to increase harvest and reduce the elk and deer populations to levels that the smaller winter range acreage can support. Potential residential development on the subject parcel will be of concern for elk for the same reasons described for bighorn sheep (the net loss of elk winter range, further impaired effectiveness of habitat within the influence of the development, and other potential habitation -related effects [e.g., free - ranging dogs and dispersed recreation originating from residences]). However, as described for sheep, elk habitat use in this area has adapted and habituated to I-70 activity, nearby subdivisions, and dispersed recreational activity. Similar to sheep, the relatively small (5.4 -acre) potential East Vail development would result in a further loss of winter range, but its location in an area whose habitat effectiveness has been reduced by existing human disturbance and development should not result in any measurable change in elk habitat use or herd size. Approximately 75% of the parcel would remain available for continued elk use. 4.3 Peregrine Falcon Peregrine falcons are a sensitive species monitored by CPW and the U.S. Forest Service. There is an active peregrine falcon nesting cliff on the opposite side of the Gore Creek valley in the vicinity of the East Vail parcel (Fig. 6). The nesting area polygon is defined as the area which includes good nesting sites and contains one or more active or inactive nest locations. The boundaries are drawn based on professional judgment to include most known nesting habitat in the vicinity. Usually these areas are mapped as polygons around cliffs and include a 0.5 mile buffer surrounding the cliffs. 6 Viable peregrine falcon nesting sites possess two components: (1) adequate nesting habitat and (2) extensive hunting habitat with an adequate prey base to support the adults and their offspring (Craig 1978). Nesting sites are located on precipitous cliffs ranging in height from 40 to 2,100 feet, averaging 200 to 400 feet tall. Several ledges, potholes, or small caves must be present in the cliff face to function as a suitable nest site. A breeding pair will frequently alternate their nesting activities to different ledges on a cliff face between years, and they will often relocate to adjacent cliff faces. As a result, protective measures must address an entire cliff complex (and potential nesting areas) rather than an individual cliff. Nesting peregrines will not tolerate excessive human encroachment or prolonged disturbance in the vicinity of the nesting cliff. Any activity or development above the nesting cliff will likely cause abandonment. Breeding peregrines become extremely agitated and may abandon the nest site if disturbance occurs during courtship, prior to the initiation of egg laying. One explanation regarding why some sites are occupied in spite of excessive human activity in the vicinity of the nesting cliff is that the falcons occupied the site early in the nesting season prior to spring increases in human activity and had eggs or young when the disturbance occurred. Once birds have eggs or young, they have a strong fidelity to their invested resources. Such birds were, therefore, attached to the site and would not abandon it at that time. The East Vail peregrines are examples of how wildlife, in general, can habituate to chronic, but benign, human activities, although residential and golf course development along the valley bottom has reduced their prey base. In Colorado, peregrines usually return to nesting cliffs in late February or early March and initiate courtship activities, which continue to mid- or late April when eggs are laid. The young hatch from mid- to late May and fledge (i.e., leave the eyrie) in mid- to late June. The young and adults remain in the vicinity of the nesting cliff up to several months after fledging. �l Extensive hunting habitat is a second key component of a viable peregrine nest site. Peregrines will frequently travel at least 10 miles from their eyrie to procure prey and they have been documented hunting up to 30 miles away from nest sites (G. Craig, CDOW, pers. comm.). It is, therefore, important to maintain the integrity of important hunting areas within at least 10 miles of the nesting cliff. All habitats within the 10 -mile radius need not be considered essential habitat, since only those areas that attract or support peregrine prey need be protected. The primary prey captured by nesting Colorado peregrines are small to moderately-sized birds, such as blackbirds, doves, robins, flickers, jays, nutcrackers, meadowlarks, and pigeons, but prey as large as waterfowl are also taken. Any habitat that supports or concentrates birds should be considered essential to locally nesting peregrines. Key hunting areas fall into two categories: (1) those habitats that concentrate or support important prey species, and (2) those habitats that expose prey and make them vulnerable to peregrine attack. Peregrines capture their prey through precipitous dives from considerable height above their quarry. Peregrines must, therefore, frequent habitats permitting this type of pursuit. Peregrines do not hunt below the forest canopy, but capture birds flying above forests or across open expanses. Larger prey are raked (with talons) or knocked out of the air and peregrines need open areas on the ground to recover them. Nesting cliffs, are generally situated at considerable heights above the surrounding terrain, so peregrines have a broad panorama from favorite hunting perches near the cliff top. The East Vail pair's 2017 nest site was within 0.5 miles of the East Vail parcel and 590 vertical feet above it. It is unknown where peregrines from this cliff complex hunt, but hunting is likely concentrated over the Gore Creek valley. The wetland and riparian complex immediately below the cliff is likely heavily used as those habitats concentrate and support higher prey densities, expose that prey base to peregrine attack more so than other local habitats, while the cliff provides a convenient hunting perch. The subject parcel contributes to the avian prey base, but unless those birds leave the parcel they are not vulnerable to peregrine attack. The air space above the parcel is likely more important hunting habitat, as it is along the entire Gore Creek Valley, as birds flying above the valley are exposed to peregrine attack. Potential residential development on the subject parcel will be of concern for peregrine falcons because of the small, but additional net loss of foraging habitat, further impaired effectiveness of habitat above and around the development, and the additive human development across from the nesting cliff. The current nesting pair has habituated to current levels of human activity and development. These include the 24/7/365 disturbance associated with I-70, the East Vail interchange and the frontage road, the Vail Pass-Tenmile bike path (immediately below the nesting cliff), and residences associated with East Vail, Booth Creek, and the Pitkin County Townhomes. Future construction and habitation of the subject parcel, buffered from the nesting cliff by distance, elevation, and more acute intervening disturbances/ activities would be more of the same type of structures and activities that should not negatively affect the nesting pair. It is also likely, with an increasing peregrine population and competition for nest cliffs, that future pairs of peregrines would also find the cliff complex viable with future development of the proposed as currently considered. That assumes that the valley's prey base remains adequate, which is likely given the avoidance of wetland and riparian habitats supporting higher prey densities and the limited amount of further development potential. The subject parcel's airspace would remain available for peregrine hunting and approximately 75% of the parcel would remain available to support potential peregrine prey. 4.4 Black Bear Colorado Parks and Wildlife have mapped two black bear seasonal ranges in the vicinity of the East Vail parcel that warrant consideration (Fig. 7). Black bear summer concentration areas are defined as those parts of the overall range where activity is greater than the surrounding overall range during that period from June 15 to August 15. This polygon extends along and above the valley bottom from east of East Vail to west of West Vail. This designation has merit overlapping the subject parcel. During the August 4 field survey, the young, open -canopy aspen stands on the west end of the property supported a moderate density of berry -rich serviceberry shrubs that represent important summer forage for bears. A human/bear conflict area is represented by the same polygon along the Gore Creek valley bottom. Such areas are defined as that portion of the overall range where two or more confirmed black bear complaints per season were received which resulted in CPW investigation, damage to persons or property (cabins, tents, vehicles, etc.), and/or the removal of the problem bear(s). This does not include damage caused by bears to livestock. Potential residential development on the subject parcel will be of concern for bears because of the small, but additional net loss of summer forage habitat, further impaired effectiveness of habitat within the influence of the development, and other potential habitation -related effects [e.g., potential garbage - handling issues. Approximately 75% of the parcel would remain available for continued bear use. Fri 0 2017 G.91. Figure 7. Black bear summer concentration area and human/bear conflict area (outlined and shaded purple) mapped by CPW in the vicinity of the East Vail parcel (red outline). 5.0 SUMMARY Several important wildlife species occur on or in the vicinity of the East Vail parcel. Proposed rezoning and platting would have no negative effects on those species. Future residential development, as currently considered, would preserve approximately 75% of the parcel, but development would remove habitat values in a 5.4 -acre area and affect, to some extent, adjacent habitat effectiveness that is not already impaired by disturbances along I-70, its frontage road, and adjacent residential developments. When future residential development is proposed, it is recommended that a wildlife mitigation plan be developed to minimize wildlife conflicts and consultation with CPW occur at that time. Please call or email me if you or others on the team have any questions. Sincerely, Ric( Thompson Certified Wildlife Biologist, Western Ecosystems, Inc., 905 West Coach Road, Boulder, CO 80302 (303) 442-6144; weiwild e aol.com 6.0 LITERATURE CITED Craig, G.R. 1978. American peregrine falcon, Falco peregr* anatum. Pages 40-45 * Essential habitat for threatened or endangered wildlife in Colorado. CDOW, Denver. 84 pp. 10 TOWN OF VA10 VAI L TOWN PLANNING AND ENVIRONMENTAL AGENDA MEMO MEETING DATE: September 25, 2017 ITEM/TOPIC: A request for a recommendation to the Vail Town Council for a Prescribed Regulations Amendment, pursuant to Section 12-3-7, Amendment, Vail Town Code, to amend Section 12-2- 2, Definitions of Words and Terms, Vail Town Code, to amend and clarify the definitions of Commercial Ski Storage, Ski Club, First Floor or Street Level, and Basement or Garden Level; to create a new definition for Ski Storage Lockers; to amend Section 12-14-21 Outdoor Display of Goods concerning ski racks, and setting forth details in regard thereto. (PEC17-0042) ATTACHMENTS: File Name Commercial—Ski—Storage—Update 092517.pdf Description Commercial Ski Storage Update Memo TOWN OF Memorandum TO: Planning and Environmental Commission FROM: Community Development Department DATE: September 25, 2017 SUBJECT: Commercial Ski Storage - Update PURPOSE The purpose of this memo is to update the Planning and Environmental Commission on issues and progress relating to the Town's commercial ski storage regulations and to present a draft of the text amendments necessary to update these regulations. There are also a few questions for the Planning ands Environmental Commission to help determine the direction of these regulations. The Planning and Environmental Commission is asked to review the questions, and draft text amendments and provide feedback on changes or additional information that may be necessary before moving forward with a formal prescribed regulations amendment. II. BACKGROUND As the Planning and Environmental Commission is aware from previous discussion on this topic, the Town's current regulations of ski storage, ski valet and ski concierge services have not kept pace with the evolving nature of the ski industry. As a result, the Town is experiencing the following challenges with the current regulations on commercial ski storage: • Regulations that are ambiguous and vague • Regulations that are inconsistent with evolving customer expectations; • Regulations that are difficult and/or impractical to enforce, resulting in a perception of inconsistent enforcement; and • Regulations that may have resulted in unintended consequences, most notably considerable storage of ski equipment outside that has both safety and aesthetic implications. On September 5, 2017, the Community Development Department presented the Commercial Ski Storage Task Force's recommendations to the Town Council. The Town Council supported the recommendations, and directed staff to begin to draft text amendments to implement the changes. On September 11, 2017, the Community Development Department presented the Commercial Ski Storage Task Force's recommendations to the Planning and Environmental Commission. The PEC requested more time to review specific code language, and requested that this topic return for further discussion. RECOMMENDATIONS OF THE TASK FORCE The current zoning regulations permit Commercial Ski Storage/Ski Clubs only in the basement or garden level of a building in the following districts: • Commercial Core 1 (CC1) • Commercial Core 2 (CC2) • Lionshead Mixed Use -1 (LMU-1) • Lionshead Mixed Use -2 (LMU-2) • Ski Base Recreation -2 (SBR -2) Following is a summary of the Task Force recommendations: • Keep the existing horizontal zoning in Storage and Ski Clubs as a permitted structure place, which only allows Commercial Ski use on the basement or garden level of a • Add graphics to improve the definitions for the following: ➢ First floor of street level ➢ Basement or garden level • Separate the definitions for Commercial Ski Storage and Ski Club • Create a separate definition for Ski Storage Lockers • Set time of day limits on the placement of ski racks outside of a business • Do not set limits on the number of racks placed on private property • Ensure that public pedestrian easements are not blocked by ski racks • Consider removing code language on outdoor displays stating that an outdoor display "shall not visually detract from or block storefront or shop window" • Clarify that a building used for delivery of skis to guests of a hotel, which is separated from the hotel property, is considered Commercial Ski Storage (i.e. Four Seasons at Gorsuch on Wall Street) IV. WHAT ARE THE IMPACTS OF THESE REGULATIONS? Depending on the amendments that are finally adopted, there may be impacts to local business, the guest experience, code enforcement, or other unintended consequences. After further consideration of these changes and clarifications, the Staff and Task Force Town of Vail Page 2 request feedback on the following questions in order to have clarity on these regulations: 1. Several businesses in Town currently place racks of skis outside their business during the day, and then roll these racks onto the first floor of the business at night, when the business is closed. These are usually racks for skis that are rented to a customer, and then returned to the same rental shop each night. In some cases, these racks may be for skis belonging to hotel guests, where the hotel has an agreement with the ski shop for storage of the skis. • Is the placement of racks of skis inside a business when the business is closed considered "Commercial Ski Storage"? If it is, then it is currently prohibited on the first floor. • How is this operation distinguished from storage of private skis for an individual? Does it matter if the skis are rented from the same business? • If it is not considered "Commercial Ski Storage", then what is it? • Is the PEC comfortable with additional businesses following this business model, which may lead to more floor area dedicated to ski racks, and less floor area dedicated to retail sales? • There may also be fire and safety issues with too many racks of skis blocking emergency access inside a business. 2. The Task Force recommended setting time limits on the placement of racks of skis outside a business. The recommended time limits are from 7:00 AM until 9:00 PM. This timeframe was recommended to allow skis to be placed outside before the lifts open, and late enough that it allows a business to remain open late, if they desire, without brining the skis in while the shop is open. Is 7:00 AM — 9:00 AM a reasonable timeframe to allow outside racks of skis? 3. Ski Clubs are currently permitted only in the basement or garden level. There is at least one Ski Club that currently operates on upper level of a building, which was permitted as the result of a determination of similar use by a previous Council. In that case, the Ski Club was determined to be similar to an "Eating and drinking establishment". Many ski clubs have a significant ski storage aspect to the club. • Should Ski Clubs be permitted on the second floor or above? • If so, this would be a change in policy. • What are the impacts of allowing Ski Clubs on the second floor or above? • The Task Force recommended no policy changes. Town of Vail Page 3 4. The Task Force recommended adding language to prohibit placement of ski racks on access easements. After further research, Staff has determined that many developments in Vail Village and Lionshead are surrounded by pedestrian access easements. For example, Arrabelle at Vail Square, the Hill Building, and Concert Hall Plaza each have significant access easements in front of shop entrances Prohibiting racks of skis on easements would severely impact businesses that operate in these developments. Should placing racks of skis on pedestrian easements be prohibited? Is there a size or number of racks that would be acceptable? This language may not be needed, as each easement is different and requires a case-by-case review, and may require a legal opinion based on the specific language in the easement document. 5. The Task Force recommended that Commercial Ski Storage and Ski Clubs be defined separately, to improve clarity in the regulations. During staff's review of this recommendation, it was determined that there exists very few differences between the two uses and those differences do not necessitate different regulatory approaches. As such, staff believes that separate definitions are not warranted. • Should there be separate definitions of Commercial Ski Storage and Ski Club? • Unless these uses will be regulated differently, there may be no reason to separate the definitions. Following are the proposed text amendments, based on the recommendations of the Task Force and as previously presented to the PEC: (New language is shown in bold and underline. Language proposed for removal is shown in strikethrough.) Title 8 — Outdoor Display on Town Property 8-7-1: PURPOSE: The purpose of this chapter is to provide standards for the licensed use of town owned property by retail establishments for outdoor display of goods. Businesses that are located in buildings without adequate privately owned exterior space may obtain a license to use adjacent town owned property for outdoor display of goods, for the purpose of increasing the vibrancy and economic vitality of the commercial cores. (Ord. 32(2007) § 2) 8-7-2: DEFINITIONS: ADMINISTRATOR: The director of the department of community development Town of Vail Page 4 and/or his or her designee that administers and enforces the guidelines outlined in this chapter. FRONTAGE, BUSINESS: The horizontal, linear dimension of any side of an above grade level that faces a major vehicular or pedestrian way and has its own public entrance for the exclusive use of said business. OUTDOOR DISPLAY. A temporary outdoor arrangement of objects, items, or products representative of the merchandise sold or rented by a retail establishment, and further regulated by section 12-14-21 of this code. PUBLIC WAY.- Means and includes a public street, easement, right of way, highway, alley, way, place, road, or bike path, and any nonexclusive utility easement. RETAIL ESTABLISHMENT: Any licensed business within the town of Vail with a physical location that is open to the public for the purpose of selling, leasing or renting tangible personal property or services at retail. (Ord. 32(2007) § 2) 8-7-3: OUTDOOR DISPLAY OF GOODS REGULATED: It shall be unlawful to place or maintain any outdoor display of goods on town owned property or on other publicly owned sidewalks or rights of way without complying with the provisions of this chapter. (Ord. 32(2007) § 2) 8-7-4: PERMIT REQUIRED.- It EQUIRED: It is unlawful for any person or retail establishment to utilize town owned property or other publicly owned sidewalks or rights of way without first securing an outdoor display on public property permit. Such permit shall be issued by the administrator and shall be pursuant to the requirements of this chapter. Permits may be approved for a time period of up to two (2) years. Permits shall be automatically renewed for additional two (2) year terms unless otherwise terminated. Prior to final approval of a permit, the retail establishment shall enter into a license agreement with the town of Vail, to be executed by the town attorney. Permit applications, application requirement, application fees and license fees are on file with the department of community development. (Ord. 32(2007) § 2) 8-7-5: ADMINISTRATIVE ACTION: The administrator shall review the application and make a determination of approval, approval with modifications, or denial within thirty (30) days of submittal of a complete application. The determination by the administrator shall become final at the next planning and environmental commission public hearing following Town of Vail Page 5 the administrator's decision, unless the decision is called up for review by the commission. Determinations shall be based on the criteria in section 8-7-6 of this chapter. All appeals shall follow the procedures outlined in section 12-3-3, "Appeals"; of this code. (Ord. 32(2007) § 2) 8-7-6: CRITERIA FOR DECISION.- Outdoor ECISION: Outdoor display of goods on town owned property or on publicly owned right of way shall be lawful at specific locations for use by a specific retail establishment approved by the administrator. Retail establishments may be allowed to utilize town owned property for the use of outdoor display should the following conditions be met.- A. et: A. Zone District: The retail establishment shall be located in one of the following zone districts.- 1. istricts:1. Commercial core 1 (CC 1) district. 2. Commercial core 2 (CC2) district. 3. Lionshead mixed use 1 (LMU-1) district. 4. Lionshead mixed use 2 (LMU-2) district. 5. Ski base/recreation 2 (SBR2) district. B. Area: The area of town owned property to be utilized shall be a maximum of twenty (20) square feet for retail establishments. Businesses displaying bicycles may be permitted to license additional square footage of town owned property at the discretion of the administrator. C. Location: The property to be licensed shall be a contiguous piece of property that is directly adjacent to the business frontage. D. Circulation: The use of town owned property for outdoor display shall not impede circulation and thus, shall not block or encroach upon the required ingress/egress of doorways, walkways, stairways, and parking or loading/delivery spaces. The placement of ski racks on pedestrian or vehicular access easements is prohibited. E. Street And Sidewalk Width: A minimum street width of twenty two feet (22 ) shall be maintained in order to allow for emergency vehicle access. Sidewalks shall remain a minimum width of six feet (6). Connection of exit discharge to the public way, as required by the adopted building code, shall not be blocked. F. Public Safety: The use of town owned property for outdoor display shall not pose any risks to public safety. The use of town owned property for outdoor display shall not block or encroach upon any fire lane, fire staging area, and shall maintain a minimum distance to fire hydrants of seven feet (7) to side or rear, and fourteen feet (14) to the front. Town of Vail Page 6 G. Maintenance Access: The use of town owned property for outdoor display shall not block or impede street sweeping, snow removal or snow storage/loading operations. The use of town owned property for outdoor display shall not block access to trash receptacles, dumpsters, mailboxes, manholes, water valves, flowerbeds or other landscape areas. H. Aesthetics: The use of town owned property for outdoor display shall not negatively impact established view corridor or acknowledged "postcard" images on shall Apt 1i/rC�Lloll detraGt fnm er b1GGk sterefrept Ar chem winrews 1. Lack Of Available Space: Retail establishments may only be located on a site without twenty (20) square feet of privately owned exterior space adjacent to the business frontage. J. Outdoor Display Fixtures: Outdoor display fixtures shall be freestanding, temporary in nature, and shall be removed from the exterior location when the business is closed. K. Code Compliance: All aspects of the outdoor display shall remain in compliance with this code and the Vail comprehensive plan. (Ord. 32(2007) § 2) L. Ski Racks: The outdoor placement of racks used for display of skis or the distribution and/or collection of rental skis, shall be prohibited between the hours of 9:00 PM and 7:00 AM. Title 12 — Definitions 12-2-2: DEFINITIONS OF WORDS AND TERMS COMMERCIAL SKI STORAGE/SK4-��: Storage for equipment (skis, snowboards, boots and poles) and/or clothing used in skiing related sports, which is available to the public or members, operated by a business, club or government organization, and where a fee is charged for hourly, daily, monthly, seasonal or annual usage. This use may have, but does not require, the following components.- A. omponents: A. Personal lockers, B. Boot dryers, C. Ski storage racks, D. Ski tuning, E. Food and beverage service, Town of Vail Page 7 F. Areas for congregation and/or socializing, G. Restrooms and/or shower facilities, H. Nonwinter activities, /. Concierge ski services, J. Retail sales, K. Business center. Ski storage that is part of a lodge, or dwelling unit, in which a fee is not charged, is not considered commercial ski storage/ski club. A building separated from the hotel property that is used for ski storage or delivering skis to a _quest is considered commercial ski storage, and is not exempt from this definition. Ski Club - A private membership organization, catering exclusively to members and quests for social, recreational and athletic purposes, who Pay a fee on daily, monthly, seasonal or annual basis, and which is focused Primarily around skiing and similar winter outdoor sports. Ski Storage Lockers - Storage for equipment (skis, snowboards, boots and poles) and/or clothing used in skiing related sports, located within a designated enclosure or cabinet which is available hourly, daily, monthly, seasonal or annual usage. Title 12 — Outdoor Display on Private Property 12-14-21: OUTDOOR DISPLAY OF GOODS: A. Purpose: The purpose of this section is to establish regulations for the outdoor display of goods by retail establishments. B. Applicability: Outdoor display of goods shall be permitted by retail establishments in the following zone districts and shall be prohibited in all zone districts not listed.- 1. isted: 1. Housing (H) district; 2. Commercial core 1 (CC 1) district; 3. Commercial core 2 (CC2) district; 4. Commercial core 3 (CC3) district; 5. Commercial service center (CSC) district; 6. Lionshead mixed use 1 (LMU-1) district; 7. Lionshead mixed use 2 (LMU-2) district; Town of Vail Page 8 8. Ski base/recreation 2 (SBR2) district. C. Permit Not Required: Outdoor display on private property, where permitted by the provisions of this title, are not subject to design review. A permit is required to obtain a license to utilize town owned property for outdoor display of goods by retail establishments, per title 8, chapter 7 of this code. D. Requirements For Outdoor Display. Where permitted, outdoor display shall be subject to the following limitations: 1. Location: The area used for an outdoor display shall be located directly in front of the retail establishment displaying the goods. Outdoor display shall be entirely upon the establishment's own property unless the retail establishment is permitted to utilize town owned property, per the requirements in title 8, chapter 7 of this code. 2. Circulation: Outdoor display shall not impede circulation and thus, shall not block or encroach upon the required ingress/egress of doorways, walkways, stairways, and parking or loading/delivery spaces. The placement of ski racks on pedestrian or vehicular access easements is prohibited. 3. Street And Sidewalk Width: A minimum street width of twenty two feet (22) shall be maintained in order to allow for emergency vehicle access. Sidewalks shall remain a minimum width of six feet (6'). Connection of exit discharge to the public way, as required by the adopted building code, shall not be blocked. 4. Public Safety. Outdoor display shall not pose any risks to public safety, shall not block or encroach upon any fire lane, and shall maintain a minimum distance to fire hydrants of seven feet (7) to side or rear, and fourteen feet (14) to the front. 5. Aesthetics: Outdoor display shall not negatively impact established view corridors or acknowledged "postcard" images and shall not visually detract from or block storefront or shop window. 6. Outdoor Display Fixtures: Outdoor display fixtures shall be freestanding, temporary in nature, and shall be removed from the exterior location when the business is closed. 7. Height: No part of any outdoor display shall extend more than six feet (6) above existing grade. 8. Signage: Sale signs may be permitted on outdoor displays, as regulated by subsection 11-6-3F of this code. No other signage is permitted on or adjacent to outdoor displays that is not otherwise approved by the administrator, subject to the regulations of title 11 of this code. Town of Vail Page 9 9. Cardboard Boxes Prohibited: Outdoor display of goods shall not include any cardboard boxes, unless part of individual packaging of goods. 10. Code Compliance: All aspects of the outdoor display shall remain in compliance with this code and the Vail comprehensive plan. (Ord. 32(2007) § 13) 11. Ski Racks: The outdoor placement of racks used for display of skis or the distribution and/or collection of rental skis, shall be prohibited between the hours of 9:00 PM and 7:00 AM. V. NEXT STEPS The next step in this process is for the Community Development Department to present a Prescribed Regulation Amendment to the Town Council on October 3, 2017, and to bring these text amendments to the Planning and Environmental Commission for a formal recommendation to Town Council adoption on October 9, 2017. Following are the upcoming meeting dates on this topic: • Town Council — October 3, 2017 — Present draft text amendments • PEC - October 9, 2017 — Public hearing and recommendation on text amendments • Town Council - October 17, 2017 — Town Council — 1s' Reading of Ordinance on text amendments • Town Council - November 7, 2017 — 2nd Reading of Ordinance on text amendments • November 17, 2017 — Vail Mountain Opening Day Town of Vail Page 10 TOWN OF VA10 VAI L TOWN PLANNING AND ENVIRONMENTAL AGENDA MEMO MEETING DATE: ITEM/TOPIC: September 11, 2017 PEC Meeting Results ATTACHMENTS: File Name pec results 091117.pdf Description September 11, 2017 PEC Meeting Results E TOWN OF VAIL' Call to Order Present: Absent: Site Visits: PLANNING AND ENVIRONMENTAL COMMISSION September 11, 2017, 1:00 PM Vail Town Council Chambers 75S. Frontage Road -Vail, Colorado, 81657 Pam Hopkins, Ludwig Kurz, John -Ryan Lockman, Karen Perez, John Rediker, and Brian Stockmar Brian Gillette 1. Vail Workforce Housing Rezoning — 3700 North Frontage Road East The purpose of this work session is to discuss issues relating to the Town's commercial ski storage regulations, and to present a draft of possible text amendments to Title 12. Applicant: Town of Vail Planner Chris Neubecker Neubecker provided an update of potential changes to the Vail Town Code. It was decided that horizontal zoning is working, but certain areas of the code require clarification and a refocus on regulations based on time, place, and manner. Neubecker discussed potential changes and their impact on outdoor display (both on town and private property), use of easements, aesthetics, and hours of operation/storage. Neubecker discussed special provisions for ground floor storage available to hotels and resorts. Separate definitions are to be created for ski storage lockers, ski clubs, and ski storage. Rediker — Asked the purpose of separating the definition of ski clubs. Neubecker responded that it is proposed to be separated because they are two (2) distinct uses. Rediker asked how businesses will be prevented from mislabeling themselves as ski clubs in order to avoid regulations. Stockmar — Asked why 9 PM was the proposed end time for ski storage. Neubecker responded that this was based on feedback from local businesses in the ski and lodging industry. Hopkins — Asked what will happen if First Tracks programs increase and require the hours of operation to begin prior to 7 AM. Neubecker responded that the hours of operation for storage can be evaluated. Rediker — Stated that he requires more time to reflect on the proposed text amendments. Asked for an additional work session on September 25, 2017. Perez — Asked if non -ski businesses were considered in establishing the hours of operation for ski storage. Neubecker responded that the proposed hours were based on the premise of allowing ski storage businesses to operate their retail business during traditional hours. Tom Higgins, American Ski Exchange — Stated his opposition to ski clubs as they can avoid regulations by simply offering a minimal amount of food and beverage. He also stated that he feels there have not been a lot of problems related to ski storage, but just a small group of businesses that do not follow existing regulations. Cheryl Ann Peter — Stated concerns that proposed changes could negatively impact local residents. Jeff Babb, Vail Resorts — Stated that the chamber of commerce was included in the task force so that they could relay information to other businesses. The impetus for the project was not to debate ski clubs, but to address changes that have occurred in the ski service industry. The purpose of the task force is to focus on improving the guest experience. Dr. Penny Wilson — Stated that she has a locker at American Ski Exchange. When the second level ski club businesses are busy they create congestion and make it difficult to access the mountain base. Encouraged the PEC to consider regulations that keep skis less visible and out of the way. Tom Neyens, Ski Valet — Has operated a ski storage business in Vail since 1988. Encouraged the PEC to maintain basement level as the only permissible level for ski storage. Feels that storing skis overnight on ground level, inside a retail shop may represent a fire hazard. Wants clarity as to what is and what is not allowed on the ground level. Stockmar — Is not sure what is proposed will resolve the issue. Is unable to provide any recommendations on how it should be addressed. Kurz — Stated that the changes proposed are reasonable and in line with changes in the ski service industry. Wants additional clarification provided based on the comments provided. Any rule we come up with is only as good as our enforcement of the code. Perez — Thinks the definition of ski storage needs to be clearly defined. Stated that the display of bicycles has become a similar issue within the town and wants bicycles to be included in the discussion, too. Hopkins — Needs additional time to review proposed text amendments. Lockman — Agrees with Commissioner Kurz in that the amendments seem minor, but wants additional time to review them. Would like to hear more from the Task Force. Rediker — Agreed that additional time for PEC review of the proposed text amendments is required. 3. A request for the review of an amendment to a Conditional Use Permit, pursuant to Section 12-9C-3, Conditional Uses; Public and private schools, Vail Town Code, in accordance with the provisions of Section 12-16-10, Amendment Procedures, Vail Town Code, to allow for a renovation and addition to the existing Red Sandstone Elementary School, a conditional use permit, pursuant to Section 12-9C-3, Conditional Uses, Public parking structure, in accordance with Title 12, Chapter 16, Conditional Use Permits, Vail Town Code, to allow for the construction of a public parking structure, and a request for the review of a variance from Section 14-6-7, Retaining Walls, Vail Town Code, in accordance with the provisions of Title 12, Chapter 17, Variances, Vail Town, to allow for the construction of a retaining wall with an exposed face height greater than six feet (6'), located at 551 North Frontage Road West/Lots 8, Block 2, Vail Potato Patch Filing 1, and setting forth details in regard thereto. (PEC17-0031) Applicant: TAB Associates Planner: Matt Panfil Motion for a Conditional Use Permit for a Public Parking Structure Motion: Approve, with three (3) conditions First: Stockmar Second: Kurz Vote: 5-1-0 Conditions: 1. The conditional use permit approval is contingent upon the applicant obtaining Town of Vail approval of an associated design review application; 2. The applicant shall revise the submitted plans to depict a minimum twenty foot (20') wide drive aisle, instead of the currently depicted twelve foot (12') wide drive aisle, along the southwest part of the access drive and in the general direction of the southwestern crosswalk and the access point for the second level of the public parking structure; and 3. The applicant shall reconfigure the proposed landscape island, located south of the proposed entrance to RSES and in the Pre -K Parking Area, to allow for a complete turn by Fire Department equipment. Motion for a Variance from Section 14-6-7, Retaining Walls, Vail Town Code Motion: Approve First: Lockman Second: Stockmar Vote: 5-1-0 (Rediker) Panfil summarized the concerns expressed by the PEC at the last meeting on August 28, 2017. Panfil then described the revisions and additional information that has been provided by the applicant. There are 3 approvals as part of the original application: 1.) amended conditional use permit for Red Sandstone Elementary School; 2.) conditional use permit for a public parking structure; and 3.) a variance for the construction of a retaining wall greater than six feet (6') in height. At the last meeting, the PEC asked for more information on safety measures for pedestrians, ADA parking, proposed signage, and impacts to public health based on vehicle exhaust near the students. Level 1 of the public parking structure now has 30 standard parking spaces, five (5) ADA parking spaces, and two (2) electric vehicle charging spaces. Special ADA parking permits will be available that will allow access to the first level regardless of the time of day. ADA parking spaces for the school will be surface spaces, not in the parking structure. Level 2 and 3 will each have 39 parking spaces. Level 3 parking passes can be assigned to employees that arrive early. Level 4 is restricted to school/faculty use, but public parking will be allowed on Level 4 when school is not in session. Stair towers will have an open design to maintain better visibility. The majority of students are accompanied by staff, and should not be in the stair towers without an adult. As requested by the PEC, a flashing crosswalk sign has been added near the main vehicular entrance off of the North Frontage Road. Turning simulations have been provided for each level, based on the size of a Chevrolet Suburban. Perez — It was indicated that all students would be accompanied by staff. Does that include students that arrive by public transit? Panfil indicated that the applicant would answer that question. Rediker — Asked if the proposed flashing signs are similar to those located in the crosswalks at the town's roundabouts. Panfil confirmed. Stockmar — Stated that the location of the parking level occupancy sign does not make sense. Panfil asked if it would be better located on the east side of the Level 1 entrance rather than the west side. Stockmar confirmed. Lockman — Asked for clarification as to the timing for access to parking structure, and when it would be open to the public. Panfil reviewed the proposed hours of operation for each level. Stockmar — Stated the retaining wall makes sense for air circulation, but wanted to know what type of protection system is in place for the space. Panfil responded that the applicant can confirm, but he believes there will be grating or other security measures. Greg Macik, TAB Associates —There is no intent for Level 3 to be closed all day. Until 7:30 AM, only Level 3 will allow public access, in order to fill it early in the day, prior to RSES student and faculty arrival. From 8:30 AM - 2:30 PM all levels will be open. It is anticipated that Level 3 will get very little use during these hours as it is the least desirable level based on its location. Push button flashing yield signs are proposed on each side of the crosswalk. In regards to on-site vehicle exhaust, the applicant team researched the topic. Every year there are new, stricter, regulations on vehicle exhaust. The applicant can also install "No Idling" signs and they will look at additional filtering methods for the exhaust from the parking structure as well as additional filtering options for the air intake at the school. In regards to the gap between the public parking structure and retaining wall, the design intent is that there is no gap from the top level of the parking structure down the retaining wall. The applicant is further refining their design to see if this is possible. Perez — Asked to confirm that people with ADA parking passes will be able to access Level 1 at any time. Macik confirmed. There was no public comment. Lockman — This has been a thorough process, and well done by staff and the applicant. The focus is on student safety and believes parking will be managed well with the automated system. Responses to our questions were provided. Supports the proposed project. Hopkins — Agreed with Lockman. Perez — Staff and applicant have done an impressive job in responding to the PEC's questions and concerns. Kurz — This applicant has been hammered by the PEC about safety and circulation. All the members of the Commission feel responsible for the safety of children at the school. As a result, it is a better project than we saw many weeks ago. He has no issue with height of the wall as it is not visible except from the structure itself. He is in favor of moving forward with the project. Stockmar — Thanked the applicant for all the changes made to the project. He supports the project. Rediker — Stated that the applicant did a great job responding to PEC concerns, though he is not overly excited about the congestion that will occur between 7:30 AM — 8:30 AM during school days as it will lead to more congestion on that road, especially during pickup. He stated he does not support the idea of adding two more stories on top of the parking structure and he encouraged the other commissioners to address that in any motion that is made. He still is concerned about installing a parking garage right next to a school and he has read studies that show exposure to tailpipe emission, even in small amounts, can have negative health impacts to children. Stockmar — Asked staff to clarify that the PEC is not being asked to approve Level 5 and 6 at this time. Panfil — Panfil confirmed and stated that if Levels 5 and 6 were to be built, the project would need to return to the PEC for an amendment to a conditional use. 4. A request for a recommendation to the Vail Town Council of an application establishing Special Development District No. 42 (Vail Mountain View Residences), pursuant to Section 12-9(A), Special Development Districts, Vail Town Code, to allow for the development of a mixed use building consisting of 12 dwelling units with 15 attached accommodation units (lock -offs), 19 accommodation units and 10 employee housing units, and related uses and improvements, located at 430 and 434 South Frontage Road (Vail Mountain View Residences on Gore Creek)/ Lot 1, Vail Village Filing 5, formerly known as part of Lot 1, a Resubdivision of Tract D, Vail Village Filing 5, and setting forth details in regard thereto. (PEC17-0006) Applicant: Lunar Vail LLC, represented by Mauriello Planning Group Planner: Jonathan Spence Motion: Table to September 25, 2017 First: Kurz Second: Perez Vote: 6-0-0 Staff requests that PEC17-0006 be tabled to September 25, 2017. 5. A request for a recommendation to the Vail Town Council for a zone district boundary amendment, pursuant to Section 12-3-7, Amendment, Vail Town Code, to allow for a rezoning of a parcel of land located at 3700 North Frontage Road East/Unplatted. The rezoning will change the Zone District from Two -Family Residential (R) district to Housing (H) district and Natural Area Preservation (NAP) district, and setting forth details in regard thereto. (PEC17-0039) Applicant: The Vail Corporation (Vail Resorts), represented by Mauriello Planning Group Planner: Chris Neubecker Motion: Approve First: Stockmar Second: Kurz Vote: 6-0-0 Referencing a PowerPoint presentation, Neubecker introduced the project by summarizing the nature of the zoning request from Two -Family Residential (R) district to Housing (H) and Natural Area Preservation (NAP) districts. As the subject property is currently zoned Two -Family Residential (R), the entire site could be developed with two- family residences. The applicant is proposing to set aside a large portion of the site for Natural Area Preservation (NAP) to focus development on a smaller area of the western portion of the site. Neubecker described the location of the site, the relevant criteria for a rezoning, and the PEC's role in making a recommendation to the Town Council for a rezoning application. Neubecker discussed the relationship between the master plan / comprehensive plan, land use plan, and zoning ordinance. If the rezoning were approved, a development plan would need to be submitted and reviewed by the PEC prior to any development occurring. An environmental impact report would also be required at that time. Neubecker reviewed the anticipated timeline for the project. Rediker — Asked about the recommendation in the staff memo to continue the item until the next PEC meeting. Neubecker responded that information from Colorado Parks and Wildlife and Colorado Geological Survey was expected, but the departments will not provide comment without a specific development plan, and thus the PEC could approve today, if it meets the criteria. Rediker asked how many two-family residential lots would fit on the subject property as currently zoned. Neubecker replied approximately 10-15 lots, but the applicant will confirm. Rediker asked how many EHUs could be provided based on the size of the proposed Housing (H) district parcel. Neubecker stated that there is no limit and that the number of units is subject to PEC discretion and review of the development plan. The applicant's representative, Dominic Mauriello of Mauriello Planning Group, provided a PowerPoint presentation and introduced the rest of the applicant's team. Chris Jarnot, Vail Resorts, discussed the need for employee housing and Vail Resorts' commitment to developing new employee housing. Jarnot discussed how the proposal could help to achieve the goals and vision of the Vail Housing Strategic Plan. Mauriello described the process required for the proposal. The proposed rezoning and plat for the subdivision are the first step in the process. The Housing (H) district requires a development plan to be approved by the PEC. According to Mauriello, the Vail Local Housing Authority (VLHA) supports the request. Mauriello then described the location of the site and its proximity to other significant development and other key features within the town. The subject property has been owned by Vail Resorts since 1961 and was annexed into the town in 1975. There has been past confusion over ownership of the parcel that influenced town planning documents. Mauriello reviewed what is currently permitted on the parcel due to its two-family residential (R) zoning. Mauriello stated that approximately 10-15 lots, with 2-3 units per lot, could be established. Mauriello described the size of the two (2) proposed zone districts and where the proposed division line of the districts will be located. It is approximately 100' from the southeast corner of the proposed Housing (H) parcel to the nearest bus stop on the North Frontage Road. Mauriello reviewed the purpose of the Housing (H) district being for employee housing. A development plan would be required to be approved by the PEC prior to any development of the site. The PEC can determine density/number of units, GRFA, and building height. Setbacks, site coverage, and landscape are established within the development standards of the Housing (H) district. Mauriello also reviewed the uses permitted and associated standards for the Natural Area Preservation (NAP) district. Mauriello emphasized that they are not currently requesting anything that would constitute a vested right because there is no specific development plan at this point. He also emphasized that the proposal is not a "Development vs. No Development" scenario. Development will occur on this property, it is up to the PEC to determine the type of development. Mauriello referenced several housing studies and plans that have demonstrated a need for employee housing within the area. Mauriello stated that wildlife and rockfall hazard were environmental characteristics specifically review by consultants. The subject property is located within a high rockfall hazard area and has slopes greater than 40%. Although an environmental impact report is not yet required, the applicant performed a geologic hazard study. The study concluded that the rockfall hazard can be mitigated. A certified wildlife biologist, Rick Thompson, has also reviewed the proposal in regards to its potential impact on wildlife. Rick Thompson explained that the study focused on the four (4) species of greatest concern: bighorn sheep, elk, peregrine falcon, and black bear. Thompson explained the range of the bighorn sheep in the area and stated that the Bighorn sheep winter range overlaps the subject property. While development of the site would result in a further loss of winter habitat, the location of the subject property is in an area whose habitat effectiveness has been reduced by existing human disturbance and development. There should be a minimal impact on the bighorn sheep habitat area associated with the development of the Housing (H) parcel. Thompson stated that the situation for elk is similar to bighorn sheep. For peregrine falcons, there should be no meaningful impact to the nesting cliff above the subject property. In regards to black bear, Thompson stated that bears are currently using the property, especially to feed in late summer. The development of the subject property may impact the black bear population, but may be addressed through wildlife mitigation plan. Thompson concluded by stating that wildlife will be impacted by any development on the subject property and the question is which type of development would minimize said impact. It is his opinion that rezoning to the Housing (H) and Natural Area Preservation (NAP) districts would minimize any negative impact to wildlife. Mauriello reviewed the applicant's responses to the rezoning criteria, including: 1.) compliance with the Vail Land Use Plan, Comprehensive Open Lands Plan, Vail 20/20 Plan, and Employee Housing Strategic Plan, 2.) suitability with the existing and potential land uses on the site and surrounding land uses, 3.) a harmonious and convenient, workable relationship among land uses, 4.) orderly growth of a viable community that serves the best interests of the community as a whole, 5.) the ability to mitigate any adverse impacts on the natural environment, 6.) consistency with the purpose statements of the proposed zone districts, and 7.) the change in conditions since the original zoning designation warrant the proposed zone district changes. Kurz — Asked what factors went into the determination of the size of the two (2) proposed zone districts. Mauriello responded that the decision was made based on geography and topography. Stockmar — Asked if the property remained Two -Family Residential (R) and went through the proper process, the subject property could be fully developed with houses and roads? Mauriello confirmed. Hopkins opposed the statement based on her belief the steep slopes would limit the amount of development on the subject property. Mauriello stated that the Two -Family Residential (R) district does not restrict construction on steep slopes. In the Housing (H) district, development cannot occur on steep slopes. Hopkins — Asked Rick Thompson about mountain goats or mountain lions. Thompson responded that mountain goats do not descend that low in elevation and mountain lions range may cover the area. Rediker asked for clarification of the source of information in determining the range for bighorn sheep. Thompson stated he relies upon Colorado Parks and Wildlife map, which was updated in the fall of 2016. Lockman asked what the secondary impact may be of the development on wildlife. Thompson stated that there may be some reduction in range as wildlife stays further away from development beyond the area of the subject property. Pets and occupant behavior could also impact the wildlife. Rediker — Stated his belief that a lot of the questions from the public will pertain to what will happen on the site and asked if there is any intention to include a free market component of the development of the site. Mauriello responded that there is no intent, unless there was a creative idea as to how such development could be incorporated. Hopkins — Asked if the applicant is considering any commercial use. Mauriello responded that they are not considering commercial uses at this time, but a developer has not yet been selected. Perez — Asked if there is an estimate for a total number of employee housing units available. Mauriello responded that it is premature, but at minimum one could assume the same number of units that would be allowed by right under existing zoning. Rediker — Asked for clarification of the steep slopes on the subject property Rediker opened the item for public comment. Julie Hansen, Board President, Falls at Vail — Concerned with the lack of a master plan for the east Vail area as there is development opportunity within the four corners of the Interstate -70 interchange. Asked if the Natural Area Preservation (NAP) district is a permanent designation. Expressed concern with flooding into the bus stop area. There are also moose in the area that were not addressed in the wildlife study. Bill Eggers — Is concerned about the impact on the Booth Falls neighborhood, which is already congested with traffic. Stated his belief that most of the people that support Vail Resorts' request live down valley. Expressed his displeasure with the amount of vehicles parked for the Booth Falls trail. Molly Morales, Vail Local Housing Authority — Expressed VLHA's support for the proposed rezoning. Dr. Penny Wilson —The Bald Mountain Road neighborhood is also impacted by the existing level of traffic congestion. Opposed to creating more traffic in the area. Disagreed with Thompson's statement that bighorn sheep do not come down to the North Frontage Road during the winter. Believes that the proposed rezoning may be the lesser of two (2) evils. Lauren Phillips, Vail Ski Patrol — Supports the rezoning of the property to allow for Vail Resorts' employees to be part of the community. Jeff Wiles — Believes something must be done to help keep employees in town or else Vail will no longer be a world class resort community. Alan Danson — Opposes the proposal due to the location of the proposal. Employee housing needs to be addressed, but not through this proposal. Suggests the town - owned property east of Solar Vail and west of Middle Creek be swapped with the subject property. Richard Leslie — Wants the PEC to deny the rezoning, but does not deny that employee housing is a town need. Believes that the applicant knows the number of units and building height that will be proposed. A development plan should be attached to any rezoning approval. Pam Stenmark — Is not necessarily against the rezoning or employee housing, but is concerned about approval without any development plan. Concerns about impacts on bus service and wildlife and the ability of the neighborhood to support a large development. Susan Bird — Is concerned that this proposal, if approved, will set a precedent for other areas of town. Alison Wadey, Vail Chamber & Business Association - Expressed the board's support for the rezoning. The serious discussion about housing is now. Don't kick this down the road just because its a hard decision Mike Steimle — Mentioned his previous experience with rezoning with the Vail Mountain School. Feels threatened by employee housing to the east and west of his property and would like the subject property to remain as is. There are too many unknowns associated with this proposal. Lee Kuhlke — Opposes the proposal. East Vail's character is completely residential and this proposal would change that. Opposes another megastructure like those to the west of the subject property. Is concerned about setting a precedent for other areas in town. Pati Marsh — Opposes the proposal. Believes it is important to maintain the existing zoning. Does not deny the need for employee housing, but this is not a reasonable solution. Believes alternative locations exist that are better for employee housing. Kim Bell Williams, Eagle County Housing Director — Eagle County is short 4,500 homes. Expressed Eagle County's support for the proposal. Believes that it is important towards creating a sense of community. Carl Cocchiarella — Believes that there is a strong sense of community as evidenced by the turnout for the public hearing. Is concerned about the impact on wildlife. Suggested Ever Vail as a better location for employee housing. Mary McDougall, member of the VLHA — VLHA is fully vested in trying to create community and has been aggressive in trying to obtain employee housing because of the danger to the community that a lack of housing represents. Expressed the need for available land and a willing private partner to create employee housing. Supports the proposal. Joe Joyce — Employee housing is critical to the town, and the proposal is a benefit to the town and the people that live and work in town. Doug Scofield — Believes that this is an essential development for the town and is a step in the right direction. Bobby Lipnick — Supports the rezoning request. Acknowledges that people do not like employee housing in their backyard. The proposal will help with the survival of the community for the next 50 years. While there is no perfect solution to the housing problem, this is a commitment to workforce housing. Recommends the applicant consider a percentage of the development be market -rate housing. Feels it is important in creating a sense of community. Michael Hazard — Believes that should the request be approved, the PEC should strongly evaluate the potential character of any housing development to ensure that it creates a sense of community. Gina Grisafi — Discussed her experience with subdividing a lot and being told that her proposal would increase density too much. Asked why Vail Resorts should be allowed to do something to improve their financial position when she was not. Brian Eggleton — As a resident of Minturn that works year-round for Ski and Snowboard Club of Vail, he supports the proposal as it will provide more affordable and employee housing within the town. Approving the proposal would allow for more of a balance between mountain and resort community. Jason Plante — Is concerned about the impact on wildlife. Does not trust just the wildlife study in making a decision. Kirk Dwyer, Ski and Snowboard Club of Vail — Supports the proposal as employee housing is a necessity within the County. Zoning needs to adapt to the conditions and be able to house young professionals. Wolf Mueller — Believes Vail Resorts should increase their employee compensation so that employees can help solve the housing problem on their own. Becky Vickers — Discussed her experience commuting from Eagle -Vail to a job with Vail Resorts. Is concerned about the impact of the proposal on bighorn sheep. John Bailey — Is concerned about the impact on wildlife, but trusts the expert studies presented. Believes there are positives associated with the proposal and supports the proposal. Public comment was closed. Stockmar — Emphasized that there is no development plan associated with the rezoning request. Discussed the issue of the potential duplex or single-family development that could be built by right on the whole parcel versus a limited area of employee housing with the guarantee of a large area of open space. Any development would require a thorough review process as the next step. Kurz — Concurs with Commissioner Stockmar. Added that he lives in the neighborhood and is familiar with the issues. The affordable housing issue is critical to the long term survival of the community. Perez — Have to find a balance between wildlife preservation, addressing density concerns, and providing employee housing. Believes there is a transparency issue created by the applicant in not specifying the number of units proposed, building height, etc. Hopkins — Stated that she believes the process the applicant will have to go through in order to get any development approved will result in a benefit to the town. Lockman — Thanked the public for their input. In regards to the request, he concurs with Commissioner Stockmar that there is no specific project associated with this request and that the PEC will have the ability to control the specifics of the project as it moves forward. Believes that the proposal meets all of the criteria required for a rezoning request. Rediker — Thanked the public for their input and urged them to continue to be involved in PEC meetings. Concurred with Commissioners Stockmar, Lockman, and Kurz and believes the project complies with the rezoning criteria. Rediker cited specific ways in which the proposal meets said criteria. Understands the concerns regarding potential density and impact on wildlife and encourages the public to maintain their interest as the project moves forward to make sure these concerns are addressed. Agrees that it is odd that an applicant can request a rezoning without a development plan, but if that is a problem, it is up to the Town Council to change the rezoning procedures. 6. A request for final review of an amendment to a conditional use permit, pursuant to Section 12-9C-3, Conditional Uses, Vail Town Code, pursuant to Title 12, Chapter 16, Vail Town Code, for an existing healthcare facility, amending the development plan to allow for the reconstruction of the east wing, including healthcare facilities, ambulance district facilities, heliport building and associated structured parking located at 180 South Frontage Road West (Vail Valley Medical Center)/Lots E, F and 2E, Vail Village Second Filing, and Lot 2E-1, Block 1, Vail Lionshead Filing 1. (PEC17-0022) Applicant: Vail Valley Medical Center Planer: Jonathan Spence Motion: Approve, with twelve (12) conditions First: Kurz Second: Stockmar Vote: 6-0-0 Conditions: 1. This Conditional Use approval is contingent upon the applicant obtaining Town of Vail approval of an associated design review application(s); 2. WMC provides a construction management plan for review and approval by town staff prior to the issuance of building permit for the East Wing; 3. Prior to the issuance of a building permit for the East Wing, the applicant shall provide an updated drainage study for review and approval; 4. Prior to the issuance of a building permit for the East Wing, the applicant shall provide an updated Traffic memo for review and approval; 5. Prior to the issuance of the first certificate of occupancy for the East Wing, the applicant shall demonstrate compliance with the required employee generation mitigation; 6. Prior to the issuance of the first certificate of occupancy for the East Wing, the applicant shall provide the town with the necessary easement or other legal instrument for public access through the property from the South Frontage Road to West Meadow Drive (the north/south pedestrian connection). A public easement for those portions of the West Meadow drive public walk that extend onto VVMC's property shall also be provided; 7. During the restoration of the W. Meadow Drive paver sidewalk, the Art Flow Line shall be restored back to its original configuration and alignment. A detailed survey of the flow line shall be completed prior to demolition, so that the flow line can be restored in the exact alignment and width. Contact Public Works department prior to reinstalling the Art Flow Line; 8. Prior to the occupancy or use of any of the identified shell space, the applicant shall have obtained an amendment to this conditional use permit, per 12-16-10, Amendment Procedures, Vail Town Code; 9. Prior to the issuance of a building permit for the East Wing, the applicant shall amend the existing development agreement with the Town of Vail to: • Outline roles and responsibilities of WMC related to the South Frontage Road improvements including: o The snow melting, operation and maintenance of the South Frontage Road and West Meadow Drive sidewalks with a recognition that the snow melting in front of the MPB may be delayed until its redevelopment; o All improvements shown on the provided plans related to improvements to the South Frontage Road that are located south of, and including, the new curb and gutter including sidewalk, concrete bus pull out, landscaping, irrigation and lighting; o A $15,000.00 contribution towards the construction of a bus stop structure; o The construction of or the payment for a maximum of two storm water inlets and 75' of associated storm sewer piping immediately adjacent to the property within the South Frontage Road ROW; and o The construction of a right turn lane if determined to be necessary through consultation with the Town of Vail and CDOT. • Update traffic fee mitigation requirements to reconcile the Transportation Impact Fee for the 118 net new trips or 110,225 net new square feet of development, in accordance with the pending new Vail Transportation Impact Fee; • Require an employee generation audit for the East Wing; and • Address obsolete or unnecessary provisions. 10. The applicant shall adhere to the Plan for Managed Parking Program, August, 2017, in all matters referenced unless amended per 12-16-10, Amendment Procedures, Vail Town Code; and 11. The applicant shall adhere to the management plan for the operation of the loading facility, included on pages 20-22 of the application narrative, unless amended per 12-16-10, Amendment Procedures, Vail Town Code. Specifically, as outlined in the WMC Site Specific Redevelopment Master Plan (pages 19-21), the allowance of loading and delivery utilizing West Meadow Drive is allowable only under a certain set of conditions. Principal among these conditions is that under no circumstances will vehicles be allowed to back in or out of the loading facility. Any vehicle unable to meet this required condition, due to size or other characteristics, shall use the West parking lot and shall at no times be permitted to access the loading facility. 12. Prior to the issuance of a Building Permit for the East Wing, the applicant shall obtain title to Lot 2E-1, Vail/Lionshead, Second Filing, Block 1, a resubdivision of Lot 2W, according to the plat to be recorded in Eagle County, Colorado. Spence introduced the application. This is the fifth, and hopefully final, hearing on this application. The Master Plan identifies the development objectives for the expansion of the hospital, 10 of the objectives are relevant to the East Wing phase. The proposal meets the development objectives of the Master Plan and the Town Code. Applicant requests a Condition of Approval contingent upon the applicant obtaining title to the adjacent property. Tom Braun, Braun Associates — We worked long and hard to identify the development objectives. These objectives made our job easier. We told you we would come back to identify the employee housing. We will buy units for deed restriction. We have identified how we meet the review criteria. A bike share program is proposed to allow and guests employees to run errands. We propose to add landscaping up on the second level, with taller trees. We will add more plantings between road and sidewalk. We will work with town staff to determine the actual size, and also working on more detail for the railing on the second floor deck. Lockman — How will the bike share be managed? Braun indicated that they will need to work on how that will happen. Rediker — Parking for contractor and workers during construction, will this be a real concern, and what are the solutions? Braun — Peak time will be 250 people working. We expect about 60 people in the first year, then about double that in year 2. Then the peak will be when we have all trades working on site. We cannot tell you there will be no parking in Lionshead, but we will direct workers where they should park. Many contractors bring their employees in shuttle vans. Public Comment — Gwen Scalpello — Asked at the last meeting of the impact of traffic on Meadow Drive. We have ambulances on Meadow Drive. Some loading and delivery will be moved to Mountain Plaza; that sounds like a good thing. Request that we get more detail on deliveries from semi -trucks. We should find out the total impact of traffic on Meadow Drive. Commissioner Comments — Lockman — Applaud applicant. Each item has been addressed as needed. Vail Health is an asset in Community. This will be a great project. I will always have concerns about parking in community. But applicant has a good plan to address parking Hopkins — Agree. Staff will make sure the restaurant looks great. Perez- I did not see if the parking plan is part of the conditions (Spence, construction management plan is part of the conditions.) Kurz — Appreciate the new landscaping, I know it's in a narrow corridor, but it will enhance that area. Traffic management will be difficult, but this applicant can handle it. Stockmar — Appreciate the work that staff and applicant have performed. The contingency space will ensure that it will be a long time before we do this again. It will be an excellent project Rediker — Impress upon staff, prior to building permit, we need to address contractor parking. That is my concern, we cannot blow it off. We can't allow them to take up parking in the parking garage; we need those spaces for our guests. Spence handed out a revised condition #9, and a new condition #12. Rediker — Read revised Condition #9, regarding the concrete pull out at South Frontage Road, to add clarification language. He also read a new Condition #12, concerning obtaining Title and ownership to Lot 213-1. 7. A request for a final recommendation to the Vail Town Council on a major amendment to Special Development District No. 36, Four Seasons, pursuant to Section 12-9A-10, Amendment Procedures, Vail Town Code, to allow for reconfiguration of existing accommodation units, fractional fee units and dwelling units, located at 1 Vail Road/Lots A -C, Vail Village Filing 2, and setting forth details in regard thereto. (PEC17-0038) Applicant: Braun Associates, Inc. Planner: Matt Panfil Motion: Approve, with conditions First: Kurz Second: Lockman Vote: 6-0-0 Conditions: 1. The exterior building changes associated with this major amendment to SDD No. 36, Four Seasons, are contingent upon the applicant obtaining Town of Vail approval of an associated design review board application for all exterior changes to the property; 2. Prior to issuance of any certificate of occupancy for any unit associated with the altering of the unit mix and/or unit count in the subject property, the applicant shall cause an offsite Town of Vail deed restriction to be recorded with the Eagle County Clerk and Recorder for an employee housing unit, with a minimum of two -bedrooms and 788 square feet, located within the Town of Vail; and 3. Prior to issuance of any building permit for altering the unit mix and/or unit count in the subject property, the applicant shall pay to the Town of Vail a traffic mitigation fee, the amount of which is yet to be determined, per net new P.M. peak hour vehicular trip. Panfil began by instructing the PEC that if any motion for approval were to be made, condition of approval number two (2) on Page 18 of the staff memo, should be changed to read, "prior to issuance of any certificate of occupancy" instead of, "prior to issuance of any building permit." The request is for a major amendment to the SDD due to the proposed change in the unit mix. There may be some minor exterior alterations which will require Design Review Board review, but they are not relevant to this specific request. Panfil reviewed the current mix of fractional fee units (FFUs), dwelling units (DUs), accommodation units (AUs), and employee housing units (EHUs) on site. The applicant is proposing to: 1.) add eight (8) AUs to increase the total number of AUs from 122 to 130; 2.) add twelve (12) DUs to increase the total number of DUs from 16 to 28; and 3.) reduce the number of FFUs from 19 to six (6). To achieve the proposed unit mix, the applicant will: 1.) convert three (3) suites to three (3) DUs; 2.) convert nine (9) FFUs to nine (9) DUs; 3.) convert four FFUs to 16 AUs; and 4.) convert two (2) suites to four (4) AUs. A total of 18 AAUs / lockoffs will be added to the twelve new DUs. There are no changes to development standards such as setbacks and building height. There is no increase in GRFA, therefore there are no inclusionary zoning fee required. However, the amendment does increase the parking demand by 19 spaces, from 211 to 230 parking spaces. The applicant is proposing 20 additional parking spaces. The additional parking spaces will be created by restriping of the parking spaces to allow for compact vehicle spaces. Said compact vehicle spaces are permitted by Town Code. There is no physical construction associated with the new parking spaces. Panfil stated that based on the change in unit mix, the commercial linkage formula generates 0.28 new employees. The applicant has proposed to deed restrict a minimum two-bedroom unit at least 788 square feet in size. Lockman — Asked about the existing 28 deed restricted units on site. Panfil responded that the 28 EHUs were negotiated as part of the original SDD agreement, prior to the existing town requirements. Tom Braun, Braun Associates, Applicant's Representative — Braun explained that since purchasing the property in November 2016, the new owners, Extell, have a new vision for the property. Braun described the history of the property, back to its former use as a Holiday Inn. He explained how the SDD, especially the proposed unit mix, has changed over time; Fractional Fee Units have been reduced multiple times. The current proposal is for 130 AUs, 28 AUs, and 6 FFUs. There is a hotel suite that is 5,000 sq. ft. in size. Someone thought that was a good idea when this was first built. Extell has a lot of data on the types of rooms in demand, and how much their guests spend in the restaurant. Fractional Fee Units were the buzz in the 90s and in response the town added FFUs as listed in the late 90s. Some Four Seasons have had successful sales of Fractional Fee Units, but some are still available for sale. In Scottsdale, they only sold one-third of the units. The reality is there are 13 unsold unites at this site. There are also more suites than needed. This property has 37 suites, which is far too many. The owners want to increase unit count and bed count in order to be able to generate funds to add revenue to a capital improvement fund. What is good for the owners is also good for the Town of Vail. The proposal works within the units on site and where changes can be made. The owners have evaluated what they want to accomplish, but also what they could achieve based on current floor plans, code considerations, and carrying capacity of the resort. There are also cost and efficiencies to consider. Braun continued by stating that there is no exterior expansion proposed. He discussed the expansion of number of parking spaces. The resort has valet parking that allows minor deviations to the standards. They will accommodate employee housing for 2.25 people, which is above and beyond the 0.28 required by code. The average AU size is approximately 500 square feet. Rediker — Asked for clarification on the new parking spaces. Braun responded that the proposal is to restripe the existing parking garage to create 20 new parking spaces. Panfil — Added that the Town Code allows 25% of parking spaces to be compact spaces. Staff calculated 21.3% of the spaces will be compact. Kurz — Asked if the layout of the garage allows for restriping without constructing spaces while still meeting code and if the applicant had data pertaining to the usage of the parking lot. Braun confirmed that the layout of the garage allows you to restripe and meet code without any additional construction. He stated that there have been days when the hotel was at 99% occupancy, such as on the Fourth of July, when there were 158 of the existing 211 parked spaces occupied. That is the most intense utilization. Kurz — Asked the applicant to define their premise of "what's good for the applicant is good for the town." Braun — The applicant is providing almost two (2) more EHUs than required. The resort will have a higher occupancy rate with the new unit mix, and that is good for the town. Rediker — Asked if the AAUs / lockoffs will be required to be offered for rent or at the option of the owner. Braun — The applicant cannot require participation in renting the unit, but they will provide incentives. At the very least, the town is assured of eight (8) new hotel rooms. Rediker — Asked for further clarification of the unit mix Tom Noonan, Extell — Some of the Fractional Fee Units will be converted to dwelling units. Perez — Asked for clarification as the language on page 14 of the staff memo. She wanted it made clear where the new deed restricted EHU will be located, on or off site. She suggested a change to the language for the second condition of approval. Public Comment — Gwen Scalpello, HOA President at 9 Vail Road — There are easements between the two properties. One is specific to parking on the Four Seasons property for 9 Vail Road residents. There is a requirement for Four Seasons to provide six (6) parking spaces for 9 Vail Road residents. She added that when the Four Seasons was first approved, increasing the number of hot beds was an issue and she understands that part of this request. Panfil — Described the existing and required parking, as well as the additional parking. Braun — Until now the six (6) spaces have been included within the garage. The applicant is adding 20 spaces. He does not believe that the requirement to accommodate parking for 9 Vail Road will be impacted. Stockmar — Asked to confirm whether or not 9 Vail Road's access to parking will be impacted by the proposed changes. Gwen Scalpello — They were valet parking, and should be accommodated. Stockmar — This project makes sense economically Kurz — Agrees. Perez — Agrees. Hopkins — Agrees. Lockman — Agrees. Rediker — Fractional fee units are not being productive. It is a benefit to the town to add accommodation units. He supports the application. 8. Approval of Minutes August 28, 2017 PEC Results Motion: Approve First: Kurz Second: Stockmar Vote: 6-0 9. Adjournment Motion: Adjourn First: Stockmar Second: Kurz Vote: 6-0 The applications and information about the proposals are available for public inspection during regular office hours at the Town of Vail Community Development Department, 75 South Frontage Road. The public is invited to attend the project orientation and the site visits that precede the public hearing in the Town of Vail Community Development Department. Times and order of items are approximate, subject to change, and cannot be relied upon to determine at what time the Planning and Environmental Commission will consider an item. Please call (970) 479-2138 for additional information. Please call 711 for sign language interpretation 48 hours prior to meeting time. Ad #: 0000119118-01 Customer: TOWN OF VAIL/PLAN DEPT/COMM DEVLMT Your account number is: 1023233 PROOF OF PUBLICATION VAIL DAILY STATE OF COLORADO COUNTY OF EAGLE I, Mark Wurzer, do solemnly swear that I am Publisher of the VAIL DAILY, that the same daily newspaper printed, in whole or in part and published in the County of Eagle, State of Colorado, and has a general circulation therein; that said newspaper has been published continuously and uninterruptedly in said County of Eagle for a period of more than fifty-two consecutive weeks next prior to the first publication of the annexed legal notice or advertisement and that said newspaper has published the requested legal notice and advertisement as requested. The VAIL DAILY is an accepted legal advertising medium, only for jurisdictions operating under Colorado's Home Rule provision. That the annexed legal notice or advertisement was published in the regular and entire issue of every number of said daily newspaper for the period of 1 insertion; and that the first publication of said notice was in the issue of said newspaper dated 9/22/2017 and that the last publication of said notice was dated 9/22/2017 in the issue of said newspaper In witness whereof, I have here unto set my hand this day, 9/25/2017. Mark Wurzer, Publisher Subscribed and sworn to before me, a notary public in and for the County of Eagle, State of Colorado this day 9/25/2017. Pamela J. Schultz, Notary Public My Commission Expires: November 1, 2019 PAMELA J. SCHULTZ NOTARY PUMIC. STATE. OF CQL4F�Ai3� i�6�R.RY iI7 #799946309Y5 6Fgr,",Wrmk0nE iresh��smtrar7,20'18 PLANNING AND ENVIRONMENTAL COMMIS- SION September 25, 20179 1:00 PM Vail Town Council Chambers 75 S. Frontage Road - Vail, Colorado, 81657 1. Call to Order 2. Main Agenda Staff requests that the report out to the Planning and Environmental Commission be tabled to De- cember 12, 2017 to address design considerations A report to the Planning and Environmental Com- mission on the Administrator's approval of an amendment to an existing Conditional Use Permit, pursuant to Section 12-16-10, Amendment Proce- dures, Vail Town Code, to allow for a steel -frame tensile fabric shelter at the softball fields spectator plaza area, located at 580 South Frontage Road East (Ford Park)/Unplatted, and setting forth details in regard thereto. (PEC17- 0032) 5 min. Applicant: Town of Vail Planner: Jonathan Spence A request for a recommendation to the Vail Town Council of an application establishing Special Devel- opment District No. 42 (Vail Mountain View Residen- ces), pursuant to Section 12-9(A), Special Develop- ment Districts, Vail Town Code, to allow for the de- velopment of a mixed use building consisting of 12 dwelling units with 15 attached accommodation units (lock -offs), 19 accommodation units and 10 employee housing units, and related uses and im- provements, located at 430 and 434 South Frontage Road (Vail Mountain View Residences on Gore Creek)/ Lot 1, Vail Village Filing 5, formerly known as part of Lot 1, a Resubdivision of Tract D, Vail Village Filing 5, and setting forth details in regard thereto. (PEC17-0006) 60 min. Applicant: Lunar Vail LLC, represented by Mauriello Planning Group Planner: Jonathan Spence A request for review of a final plat, pursuant to Title 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for a subdivision of a parcel located at 3700 North Frontage Road East/Unplatted, and setting forth details in regard thereto. (PEC17-0041) 30 min. Applicant: Mauriello Planning Group Planner: Chris Neubecker A request for a recommendation to the Vail Town Council for a Prescribed Regulations Amendment, pursuant to Section 12-3-7, Amendment, Vail Town Code, to amend Section 12-2-2, Definitions of Words and Terms, Vail Town Code, to amend and clarify the definitions of Commercial Ski Storage, Ski Club, First Floor or Street Level, and Basement or Garden Level; to create a new definition for Ski Storage Lockers; to amend Section 12-14-21 Out- door Display of Goods concerning ski racks, and setting forth details in regard thereto. (PEC17-0042) 60 min. Applicant: Town of Vail Planner: Chris Neubecker 3. Approval of Minutes September 1 1 , 2017 PEC Meeting Results 4. Adjournment The applications and information about the propos- als are available for public inspection during regular office hours at the Town of Vail Community Devel- opment Department, 75 South Frontage Road. The public is invited to attend the project orientation and the site visits that precede the public hearing in the Town of Vail Community Development Department. Times and order of items are approximate, subject to change, and cannot be relied upon to determine at what time the Planning and Environmental Com- mission will consider an item. Please call (970) 479- 2138 for additional information. Please call 711 for sign language interpretation 48 hour prior to meet- ing time. Community Development Department Published in the Vail Daily September 22, 2017 00001 191 18 Ad #: 0000110860-01 Customer: TOWN OF VAIL/PLAN DEPT/COMM DEVLMT Your account number is: 1023233 PROOF OF PUBLICATION VAIL DAILY STATE OF COLORADO COUNTY OF EAGLE I, Mark Wurzer, do solemnly swear that I am Publisher of the VAIL DAILY, that the same daily newspaper printed, in whole or in part and published in the County of Eagle, State of Colorado, and has a general circulation therein; that said newspaper has been published continuously and uninterruptedly in said County of Eagle for a period of more than fifty-two consecutive weeks next prior to the first publication of the annexed legal notice or advertisement and that said newspaper has published the requested legal notice and advertisement as requested. The VAIL DAILY is an accepted legal advertising medium, only for jurisdictions operating under Colorado's Home Rule provision. That the annexed legal notice or advertisement was published in the regular and entire issue of every number of said daily newspaper for the period of 1 insertion; and that the first publication of said notice was in the issue of said newspaper dated 9/8/2017 and that the last publication of said notice was dated 9/8/2017 in the issue of said newspaper In witness whereof, I have here unto set my hand this day, 9/11/2017. Mark Wurzer, Publisher Subscribed and sworn to before me, a notary public in and for the County of Eagle, State of Colorado this day 9/11/2017. Jerilynn Medina, Notary Public My Commission Expires: August 3, 2020 THIS ITEM MAY AFFECT YOUR PROPERTY PUBLIC NOTICE NOTICE IS HEREBY GIVEN that the Planning and Environmental Commission of the Town of Vail will hold a public hearing in accordance with section 12-3-6, Vail Town Code, on September 25, 2017 at 1.00 pm in the Town of Vail Munici- pal Building. A request for review of a final plat, pursuant to Ti- tle 13 Chapter 4, Minor Subdivisions, Vail Town Code, to allow for a subdivision of a parcel locat- ed at 3700 North Frontage Road East/Unplatted, and setting forth details in regard thereto. (PEC17- 0041) Applicant: Vail Resorts, represented by Mauriello Planning Group Planner_ Chris Neubecker A request for a recommendation to the Vail Town Council for a Prescribed Regulations Amend- ment, pursuant to Section 12-3-7, Amendment, Vail Town Code, to amend Section 12-2-2, Defini- tions of Words and Terms, Vail Town Code, to amend and clarify the definitions of Commercial Ski Storage, Ski Club, First Floor or Street Level, and Basement or Garden Level; to create a new definition for Ski Storage Lockers; to amend Sec- tion 12-14-21 Outdoor Display of Goods concern- ing ski racks, and setting forth details in regard thereto. (PEC17-0042) Applicant: Town of Vail Planner: Chris Neubecker The applications and information about the pro- posals are available for public inspection during of- fice hours at the Town of Vail Community Develop- ment Department, 75 South Frontage Road. The public is invited to attend site visits. Please call 970-479-2138 for additional information -Sign lan- guage interpretation available upon request with 24-hour notification, dial 711. Published September 8, 2017i n the Vail Daily. (00001 10860)