HomeMy WebLinkAboutDivision 31 - Earthwork.pdfTHE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
SITE CLEARING 31 1000-1
SECTION 31 1000 - SITE CLEARING
PART 1 - GENERAL
1.1 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract, including General and Supplementary
Conditions and Division 1 Specification Sections, apply to this Section.
1.2 SUMMARY
A. This Section includes the following:
1. Protecting existing trees, shrubs, groundcovers, plants, grass, and other vegetation to
remain or as designated by Owner’s Representative in pre-construction conference.
2. Removing existing trees, shrubs, groundcovers, plants, grass, and other vegetation.
3. Clearing and grubbing.
4. Stripping and stockpiling topsoil.
5. Removing above- and below-grade site improvements.
6. Disconnecting, capping or sealing, and removing site utilities.
7. Removing existing fill.
B. Related Sections include the following:
1. Division 31 Section "Earth Moving" for soil materials, excavating, backfilling, and site
grading.
2. Division 31 Section “Temporary Erosion and Sedimentation Control” for storm water
erosion and sediment mitigation.
1.3 DEFINITIONS
A. Topsoil: Natural or cultivated surface-soil layer containing organic matter and sand, silt, and
clay particles; friable, pervious, and black or a darker shade of brown, gray, or red than
underlying subsoil; reasonably free of subsoil, clay lumps, gravel, and other objects more than 2
inches (50 mm) in diameter; and free of subsoil and weeds, roots, toxic materials, or other
nonsoil materials.
B. Tree Protection Zone: Area surrounding individual trees or groups of trees to be protected
during construction, and defined by the drip line of individual trees or the perimeter drip line of
groups of trees, unless otherwise indicated.
1.4 MATERIAL OWNERSHIP
A. Except for stripped topsoil or other materials indicated to be stockpiled or to remain on Owner's
property, cleared materials shall become Contractor's property and shall be removed from
Project site.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
SITE CLEARING 31 1000-2
1.5 SUBMITTALS
A. Photographs or videotape, sufficiently detailed, of existing conditions of trees and plantings,
adjoining construction, and site improvements that might be misconstrued as damage caused by
site clearing.
B. Record drawings, identifying and accurately locating capped utilities and other subsurface
structural, electrical, and mechanical conditions. Information required may also be included in
Division 1 Section "Project Record Documents."
1.6 QUALITY ASSURANCE
A. Preconstruction Conference: Conduct conference at Project site as directed by Owner’s
Representative prior to start of construction. Contractor to comply with requirements, which
may also be included in Division 1 Section "Project Management and Coordination."
1.7 PROJECT CONDITIONS
A. Traffic: Minimize interference with adjoining roads, streets, walks, and other adjacent occupied
or used facilities during site-clearing operations.
1. Do not close or obstruct streets, walks, or other adjacent occupied or used facilities
without permission from Owner’s Representative and authorities having jurisdiction.
2. Provide alternate routes around closed or obstructed traffic ways if required by authorities
having jurisdiction.
B. Improvements on Adjoining Property: Authority for performing indicated removal and
alteration work on property adjoining Town of Vail property will be obtained by Owner’s
Representative before award of Contract. Authority and permits for performing indicated
removal and alteration work on adjacent rights-of-way shall be obtained by Contractor.
1. Do not proceed with work on adjoining property until directed in writing by Owner’s
Representative.
C. Protect improvements on adjacent and Town of Vail property.
D. Salvable Improvements: Carefully remove items indicated to be salvaged and store on Town of
Vail premises where indicated.
E. Utility Locator Service: Notify utility locator service for area where Project is located before
site clearing.
F. Do not commence site clearing operations until temporary erosion and sedimentation control
measures are in place.
G. Restore damaged improvements to their original condition, as acceptable to parties having
jurisdiction.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
SITE CLEARING 31 1000-3
PART 2 - PRODUCTS
2.1 SOIL MATERIALS
A. Satisfactory Soil Materials: Requirements for satisfactory soil materials are specified in
Division 31 Section "Earth Moving," (PART 2 – PRODUCTS).
PART 3 - EXECUTION
3.1 PREPARATION
A. Protect and maintain benchmarks, survey control points, monuments, property line pins and
other reference points from disturbance during construction. If disturbed or destroyed, restore
or replace by a registered Colorado Professional Land Surveyor at no cost to Project Owner.
B. Provide erosion control measures to prevent soil erosion and discharge of soil-bearing water
runoff or airborne dust from leaving project site.
C. Locate and clearly flag trees and vegetation to remain or to be relocated.
D. Protect existing site improvements to remain from damage during construction.
1. Restore or replace damaged improvements to their original condition, as acceptable to
Owner’s Representative.
3.2 TREE PROTECTION
A. Erect and maintain temporary fencing around drip line of individual trees or around perimeter
drip line of groups of trees to remain before starting site clearing. Remove fence when
construction is complete.
1. Do not store construction materials, debris, or excavated material within fenced area.
2. Do not permit vehicles, equipment, or foot traffic within fenced area.
3. Maintain fenced area free of weeds and trash.
B. Do not excavate within tree protection zones, unless otherwise indicated.
C. Where excavation for new construction is required within drip line of trees, hand clear and
excavate to minimize damage to root systems. Use narrow-tine spading forks, comb soil to
expose roots, and cleanly cut roots as close to excavation as possible.
1. Cover exposed roots with burlap and water regularly.
2. Temporarily support and protect roots from damage until they are permanently relocated
and covered with soil.
3. Coat cut faces of roots more than 1-1/2 inches (38 mm) in diameter with an emulsified
asphalt or other approved coating formulated for use on damaged plant tissues.
4. Cover exposed roots with wet burlap to prevent roots from drying and backfill with soil
as soon as possible.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
SITE CLEARING 31 1000-4
D. Repair or replace trees and vegetation indicated to remain that are damaged by construction
operations, in a manner approved by Owner’s Representative.
1. Employ a qualified arborist, licensed in jurisdiction where Project is located, to submit
details of proposed repairs and to repair damage to trees and shrubs.
2. Replace trees that cannot be repaired and restored to full-growth status, as determined by
the qualified arborist.
3.3 UTILITIES
A. Contractor will locate, identify, arrange for disconnect and seal or cap off utilities indicated to
be removed before site clearing.
1. Verify that utilities indicated as abandoned have been disconnected and capped before
proceeding with site clearing.
2. Arrange with utility companies having jurisdiction to shut off indicated utilities.
B. Existing Utilities: Do not interrupt utilities serving facilities occupied by the Town of Vail or
others unless permitted under the following conditions and then only after arranging to provide
temporary utility services according to requirements indicated:
1. Notify Owner’s Representative not less than two days in advance of proposed utility
interruptions.
2. Do not proceed with utility interruptions without Owner’s Representative’s written
permission.
C. Excavate for and remove underground utilities indicated to be removed.
D. Removal of underground utilities may also be included in Division 2 Sections covering site
utilities. Removal of underground utilities may also be included in Division 15 Mechanical or
Division 16 Electrical Sections.
E. After removal of underground utilities, as indicated, properly cap and/or plug existing lines to
remain in accordance with authorities having jurisdiction.
3.4 CLEARING AND GRUBBING
A. Remove obstructions, trees, shrubs, grass, and other vegetation to permit installation of new
construction. Removal includes digging out stumps and obstructions and grubbing roots.
1. Do not remove trees, shrubs, and other vegetation indicated to remain or to be relocated.
2. Cut minor roots and branches of trees indicated to remain in a clean and careful manner
where such roots and branches obstruct installation of new construction.
3. Grind stumps and completely remove roots, obstructions, and debris extending to a depth
of 18 inches (450 mm) below exposed subgrade.
4. Use only hand methods for grubbing within drip line of remaining trees.
5. Chip removed tree branches and dispose of off-site.
B. Fill depressions caused by clearing and grubbing operations with satisfactory soil material
unless further excavation or earth moving is indicated.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
SITE CLEARING 31 1000-5
1. Place fill material in horizontal layers not exceeding a loose depth of 8 inches (200 mm),
and compact each layer to a density equal to adjacent original ground.
3.5 TOPSOIL STRIPPING
A. Remove sod and grass before stripping topsoil.
B. Strip topsoil to whatever depths are encountered or as determined by Geotechnical Engineer in a
manner to prevent intermingling with underlying subsoil or other waste materials.
1. Remove subsoil and nonsoil materials from topsoil, including trash, debris, weeds, roots,
and other waste materials.
C. Stockpile topsoil materials away from edge of excavations without intermixing with subsoil.
Grade and shape stockpiles to drain surface water. Cover to prevent windblown dust.
1. Limit height of topsoil stockpiles to 72 inches (1800 mm) unless authorized by Owner’s
Representative.
2. Do not stockpile topsoil within drip line of remaining trees.
3. Dispose of excess topsoil as specified for waste material disposal.
4. Stockpile surplus topsoil to allow for respreading a thicker layer of topsoil.
3.6 SITE IMPROVEMENTS
A. Remove existing above and below grade improvements as indicated and as necessary to
facilitate new construction.
B. Remove slabs, paving, curbs, gutters, and aggregate base as indicated on plans.
1. Unless existing full-depth joints coincide with line of demolition, neatly saw-cut length
of existing pavement to remain before removing existing pavement. Saw-cut faces
vertically.
2. Paint cut ends of steel reinforcement in concrete to remain to prevent corrosion.
C. Remove existing fill. Refer to Geotechnical Investigation and/or drawings for information
regarding suitability for re-use and estimates of location/extent of existing fill.
3.7 DISPOSAL
A. Disposal: Remove surplus soil material, unsuitable topsoil, obstructions, demolished materials,
and waste materials including trash and debris, and legally dispose of them off Town of Vail
property.
1. Separate recyclable materials produced during site clearing from other nonrecyclable
materials. Store or stockpile without intermixing with other materials and transport them
to recycling facilities.
END OF SECTION 31 1000
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-1
SECTION 31 2000 - EARTH MOVING
PART 1 - GENERAL
1.1 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract, including General and Supplementary
Conditions and Division 1 Specification Sections, apply if provided, to this Section.
B. Additional information concerning earth moving may be found on the civil drawings, in the
project geotechnical report and Town of Vail Development standards. In case of conflict
between the drawings, jurisdictional criteria and the information specified herein, the more
stringent requirements shall govern.
C. Additional information concerning earth moving may be found in the geotechnical investigation
report by < > dated < >. All requirements of
this report shall be followed. The information shown in this report is for information and it
shall be the Contractor’s responsibility to field verify conditions indicated.
1.2 SUMMARY
A. This Section includes the following:
1. Preparing and grading subgrades for slabs-on-grade, walks, pavements, lawns and
grasses, and exterior plants.
2. Excavating and backfilling for buildings and structures including overexcavation of
existing unsatisfactory on-site soil materials and replacement with structural fill.
3. Drainage course for slabs-on-grade.
4. Subbase and base course for asphalt or concrete paving.
5. Subsurface drainage backfill for walls and trenches.
B. Related Sections include the following:
1. Division 31 Section "Site Clearing" site stripping, grubbing, stripping and stockpiling
topsoil, and removal of above- and below-grade improvements and utilities.
2. Division 33 Section "Subdrainage" for drainage of foundations, slabs-on-grade, walls,
and landscaped areas.
3. Division 31 Section “Trenching and Backfilling” for excavating and backfilling of
utilities.
4. Division 31 Section “Temporary Erosion and Sedimentation Control” for erosion and
sedimentation control measures.
C. Permits and Fees: Obtain and pay for all permits and fees required for the work of this section,
including erosion and sediment control and water quality permits required by the Town of Vail
and the Colorado Department of Public Health and Environment, Water Quality Control Divi-
sion.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-2
1.3 DEFINITIONS
A. Backfill: Soil material used to fill an excavation.
1. Initial Backfill: Backfill placed beside and over pipe in a trench, including haunches to
support sides of pipe.
2. Final Backfill: Backfill placed over initial backfill to fill a trench.
B. Base Course: Course placed between the subbase course and hot-mix asphalt paving.
C. Bedding Course: Course placed over the excavated subgrade in a trench before laying pipe.
D. Borrow Soil: Satisfactory soil imported from off-site for use as fill or backfill approved by
Geotechnical Engineer.
E. Drainage Course: Course supporting the slab-on-grade that also minimizes upward capillary
flow of pore water.
F. Excavation: Removal of all material of whatever character required for the work encountered
above subgrade elevations and to lines and dimensions indicated, including boulders. See
Section 3.4 for definition of unclassified and classified excavation.
G. Authorized Additional Excavation: Excavation below subgrade elevations or beyond indicated
lines and dimensions as directed or approved by Owners Representative and the testing and
inspections agency to correct unsatisfactory conditions. Authorized additional excavation and
replacement material will be paid for according to Contract Provisions for changes in the
Work.
H. Bulk Excavation: Excavation more than 10 feet (3 m) in width and more than 30 feet (9 m) in
length.
I. Unauthorized Excavation: Excavation below subgrade elevations or beyond indicated lines and
dimensions without direction by Owner’s Representative. Unauthorized excavation including
disposition of overexcavated materials and other work resulting from slides, cave-ins, swelling,
upheaval, or remedial work, as well as remedial work directed by Owner’s Representative,
shall be without additional compensation.
J. Fill: Fill is all material placed to raise the grade of the site or to backfill excavation, upon which
the Geotechnical Engineer has made sufficient tests and observations to enable him to issue a
written statement that, in his opinion, the fill has been placed and compacted in accordance
with the requirements of these specifications.
K. Structural Fill: Select granular material for use below floor slabs and to 5-feet-0-inches beyond
building lines. On-site material may be used if approved by the Geotechnical Engineer.
L. Underslab Gravel: Imported Class 6 road base per Colorado Department of Transportation
Standard Specifications for Road and Bridge Construction (current addition) or material
approved by Geotechnical Engineer.
M. Rock Excavation: Rock material in beds, ledges, unstratified masses, conglomerate deposits,
and boulders of rock material that exceed 1 cu. yd. (0.76 cu. m) for Bulk Excavation or 3/4 cu.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-3
yd. (0.57 cu. m) for footing, trench, and pit excavation which in the Geotechnical Engineer’s
opinion cannot be removed by rock excavating equipment equivalent to the following in size
and performance ratings, without systematic drilling, ram hammering, ripping, or blasting,
when permitted:
1. Excavation of Footings, Trenches, and Pits: Late-model, track-mounted hydraulic
excavator; equipped with a 42-inch- (1065-mm-) wide, maximum, short-tip-radius rock
bucket; rated at not less than 138-hp (103-kW) flywheel power with bucket-curling force
of not less than 28,090 lbf (125 kN) and stick-crowd force of not less than 18,650 lbf (83
kN); measured according to SAE J-1179.
2. Bulk Excavation: Late-model, track-mounted loader; rated at not less than 210-hp (157-
kW) flywheel power and developing a minimum of 48,510-lbf (216-kN) breakout force
with a general-purpose bare bucket; measured according to SAE J-732.
N. Structures: Buildings, footings, foundations, retaining walls, slabs, tanks, curbs, mechanical
and electrical appurtenances, or other man-made stationary features constructed above or
below the ground surface.
O. Subbase Course: Course placed between the subgrade and base course for hot-mix asphalt
pavement, or course placed between the subgrade and a cement concrete pavement or a cement
concrete or hot-mix asphalt walk.
P. Subgrade: Surface or elevation remaining after completing excavation, or top surface of a fill or
backfill immediately below subbase, drainage fill, or topsoil materials.
Q. Utilities: Include on-site underground pipes, conduits, ducts, and cables, as well as
underground services within buildings.
1.4 SUBMITTALS
A. Material Test Reports: Provided by Project Owner from a qualified testing agency indicating
and interpreting test results for compliance of the following with requirements indicated:
1. Classification according to ASTM D 2487 of each on-site or borrow soil material
proposed for fill and backfill.
2. Laboratory compaction curve according to ASTM D 698 for each on-site or borrow soil
material proposed for fill and backfill.
B. Preexcavation Photographs or Videotape: Show existing conditions of adjoining construction
and site improvements, including finish surfaces that might be misconstrued as damage caused
by earth moving operations. Submit before earth moving begins.
1.5 QUALITY ASSURANCE
A. Comply with applicable codes, ordinances, regulations, references and standards in effect at bid
date:
1. Uniform Building Code (UBC) or International Building Code (IBC) per jurisdiction cri-
teria.
2. American Society for Testing and Materials (test methods as specified hereafter) (ASTM).
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-4
3. State and local codes.
B. In case of conflict between the above codes, regulations, references and standards and these
specifications, the more stringent requirements shall govern.
C. Testing Agency: The Project Owner will employ a qualified independent Geotechnical testing
agency. Contractor shall furnish testing agency access to work, facilities and incidental labor
required for testing. Notify the testing and inspection agency not less than 48 hours in advance
of all work requiring testing.
D. Geotechnical Engineer: All materials and operations under this section of the specifications
shall be executed under the supervision of a Geotechnical Engineer who will place qualified
personnel on the site during earth moving operations as necessary.
The Geotechnical Engineer shall approve all foundation excavations and give written approval
of the completed foundations to the Owner’s Representative at the following times:
1. When excavations are first open.
2. Just prior to placing of concrete, shall test and control the fill compaction, approve the
materials and method of placing and compacting and give written approval to the Own-
er’s Representative that all bearing surfaces and fill requirements have been inspected.
3. The Contractor shall be responsible to notify the Geotechnical Engineer when tests are to
be made.
E. For approval of imported or on-site fill material, notify the Geotechnical Engineer at least four
(4) working days in advance of intention to import material, designate the proposed borrow area
and permit the Geotechnical Engineer to sample as necessary from the borrow area for the pur-
pose of making acceptance tests to prove the quality of the material. The Geotechnical Engi-
neer report on the acceptability shall be final and binding.
F. Reference Standards:
Compaction Standard: Standard Proctor Density ASTM D698.
G. Preconstruction Conference: Conduct conference at Project site as directed by Owner’s
Representative prior to start of construction. Contractor to comply with requirements, which
may also be included in Division 1 Section "Project Management and Coordination."
1.6 PROJECT CONDITIONS
A. Existing Utilities: Locations, sizes and depths or invert elevations of existing utilities as shown
on the drawings are based on information provided by others, and believed to be correct, but
may not be absolutely so. Such information is therefore presented only as approximations, and
should be verified prior to construction. Protect from damage any sewer, water, gas, electric,
phone or other pipe lines or conduits uncovered during the work until they have been examined
by the Owner’s Representative. If such lines are found to be abandoned and not in use, remove
affected sections without extra cost. If such lines are found to be in use, carefully protect and
carry on work around them. If Owner’s Representative deems it advisable to move such lines,
Project Owner will pay cost of moving. Do not interrupt utilities serving facilities occupied by
Town of Vail or others unless permitted in writing by Owner’s Representative and then only af-
ter arranging to provide temporary utility services according to requirements indicated.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-5
1. Contact utility-locator service for area where project is located before excavating.
2. Notify Owner’s Representative not less than two (2) days in advance of proposed utility
interruptions.
3. Do not proceed with utility interruptions without Owner’s Representative's written
permission.
B. Demolish and completely remove from site existing underground utilities indicated to be re-
moved. Coordinate with utility companies to shut off services if lines are active.
C. Remove all existing fill deemed by Geotechnical Engineer to be unsatisfactorily placed.
D. Existing Contours and Elevations: Contours and spot elevations of existing ground elevations
at the site, and approximate elevations of finish grade cuts, fills, and excavations for the Work
are shown on Drawings. Contours and elevations for existing ground lines are based on infor-
mation provided by others, and are believed to be correct, but may not be absolutely so. Exist-
ing contours and elevations should therefore be considered approximate, and should be verified
at the site prior to construction.
E. Verification of Existing Conditions: Visit the site prior to submission of bids. Verify existing
conditions, elevations, and contours. In the event of discrepancies between existing conditions
and those indicated on the Contract Documents or survey, contact the Owner’s Representative
for clarification.
F. Existing Benchmarks: Carefully preserve and maintain existing benchmarks, monuments,
property line pins, and other reference points. If disturbed or destroyed, restore or replace by a
Registered Colorado Professional Land Surveyor at no additional cost to Project Owner.
G. Frost Protection: When freezing temperatures may be expected, do not excavate to the full
depth indicated unless the footing or slabs are to be poured immediately after the excavation
has been completed. If placing of concrete is delayed, protect the bottoms of excavations from
frost until concrete is placed.
1.7 WARRANTY
Settlement in backfill, fill or in structures built over backfill or fill, which may occur within the
specified project warranty period, shall be corrected at no cost to the Project Owner. Any struc-
tures damaged by settlement shall be restored to their original condition by the Contractor, at no
cost to the Project Owner.
PART 2 - PRODUCTS
2.1 SOIL MATERIALS
A. General: Provide borrow soil materials when sufficient satisfactory soil materials are not
available from excavations.
B. Satisfactory Soils: Shall meet approval of Geotechnical Engineer and shall be free of rock or
gravel larger than [3 inches (75 mm)] in any dimension, debris, waste, frozen materials,
vegetation, and other deleterious matter. Clean, on-site, natural soils, or imported materials, as
approved by the Geotechnical Engineer.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-6
C. Unsatisfactory Soils: Soil Classification Groups A-2-6, A-2-7, A-4, A-5, A-6, and A-7
according to AASHTO M 145, or a combination of these groups, as identified by the
Geotechnical Engineer.
1. Unsatisfactory soils also include satisfactory soils not maintained within 2 percent of
optimum moisture content at time of compaction.
D. Backfill and Fill: Approved by Geotechnical Engineer.
E. Structural Fill: Approved by Geotechnical Engineer.
F. Subbase Material: Naturally or artificially graded mixture of natural or crushed gravel, crushed
stone, and natural or crushed sand; ASTM D 2940; with at least 90 percent passing a 1 ½-inch
(37.5-mm) sieve and not more than 12 percent passing a No. 200 (0.075-mm) sieve.
G. Base Course: Naturally or artificially graded mixture of natural or crushed gravel, crushed
stone, and natural or crushed sand; ASTM D 2940; with at least 95 percent passing a 1 ½-inch
(37.5-mm) sieve and not more than 8 percent passing a No. 200 (0.075-mm) sieve.
H. Engineered Fill: Naturally or artificially graded mixture of natural or crushed gravel, crushed
stone, and natural or crushed sand; ASTM D 2940; with at least 90 percent passing a 1 ½-inch
(37.5-mm) sieve and not more than 12 percent passing a No. 200 (0.075-mm) sieve.
I. Bedding Course: Naturally or artificially graded mixture of natural or crushed gravel, crushed
stone, and natural or crushed sand; ASTM D 2940; except with 100 percent passing a 1-inch
(25-mm) sieve and not more than 8 percent passing a No. 200 (0.075-mm) sieve.
J. Drainage Course: Narrowly graded mixture of washed crushed stone, or crushed or uncrushed
gravel; ASTM D 448; coarse-aggregate grading Size 57; with 100 percent passing a 1 ½-inch
(37.5-mm) sieve and 0 to 5 percent passing a No. 8 (2.36-mm) sieve.
K. Filter Material: Narrowly graded mixture of natural or crushed gravel, or crushed stone and
natural sand; ASTM D 448; coarse-aggregate grading Size 67; with 100 percent passing a 1-
inch (25-mm) sieve and 0 to 5 percent passing a No. 4 (4.75-mm) sieve.
L. Sand: ASTM C 33; fine aggregate, natural, or manufactured sand.
M. Impervious Fill: Clayey gravel and sand mixture capable of compacting to a dense state.
2.2 GEOTEXTILES
A. Subsurface Drainage and Separation Geotextile: Nonwoven needle-punched geotextile,
manufactured for subsurface drainage applications, made from polyolefins or polyesters; with
elongation greater than 50 percent; complying with AASHTO M 288. Utilize Mirafi 140N or
as recommended by Geotechnical Engineer.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-7
PART 3 - EXECUTION
3.1 PREPARATION
A. Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by
settlement, lateral movement, undermining, washout, and other hazards created by earth
moving operations.
B. Preparation of subgrade for earth moving operations including removal of vegetation, topsoil,
debris, obstructions, and deleterious materials from ground surface is specified in Division 31
Section "Site Clearing."
C. Protect and maintain erosion and sedimentation controls, which are specified in Division 31
Section "Temporary Erosion and Sediment Control," during earth moving operations. Provide
erosion control measures to prevent erosion or displacement of soils and discharge of soil
bearing water runoff or airborne dust to adjacent properties and rights-of-way.
D. Protect subgrades and foundation soils against freezing temperatures or frost. Provide
protective insulating materials as necessary.
E. Cold Weather Work: Prevent frost from entering bearing stratus upon which construction will
take place or in areas where fill will be placed in that season.
3.2 DEWATERING
A. Prevent surface water and subsurface ground water from entering excavations, from ponding on
prepared subgrades, and from flooding Project site and surrounding area.
B. Protect subgrades from softening, undermining, washout, and damage by rain or water
accumulation.
1. Reroute surface water runoff away from excavated areas. Do not allow water to
accumulate in excavations. Do not use excavated trenches as temporary drainage
ditches.
2. Install a dewatering system to keep subgrades dry and convey ground water away from
excavations. Maintain until dewatering is no longer required.
3. Obtain and comply with all provisions of the Colorado Department of Public Health and
Environment, Water Quality Control Division, Construction Dewatering Permit.
C. Protection of Persons and Property:
1. Provide all necessary measures to protect workmen and passersby. Barricade open exca-
vations occurring as part of the Work, as required by municipal or other authorities hav-
ing jurisdiction.
2. Protect adjacent streets, roadways, and properties throughout the entire operation. Protect
newly graded areas from destruction by weather or runoff. Protect structures, utilities,
sidewalks, pavements, and other improvements from damage caused by settlement, lat-
eral movement, undermining, washout, and other hazards created by earth moving opera-
tions.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-8
3.3 EXPLOSIVES
A. Explosives: Do not use explosives.
3.4 EXCAVATION, GENERAL
A. Unclassified Excavation: All excavation (other than rock excavation) is considered as
unclassified and is defined as removal of all material encountered, regardless of soil type.
Excavate to subgrade elevations regardless of the character of surface and subsurface
conditions encountered. Unclassified excavated materials may include soil materials, and
obstructions. Unclassified excavation is considered normal excavation and no extra costs will
be allowed.
1. If excavated materials intended for fill and backfill include unsatisfactory soil materials
and rock, replace with satisfactory soil materials.
2. Remove material of every nature or description encountered in obtaining required lines
and grades. Excavate and/or place and compact fill to provide for building pad eleva-
tion(s) required by drawings.
3. Excavate wide enough at foundations and retaining walls to permit erection and removal
of forms, application of dampproofing or waterproofing.
4. Pitch grading around excavations to prevent water from running into excavated areas.
5. Pre-rip hardpan and soft bedrock with single-tooth ripper or other suitable equipment to
facilitate excavation with conventional earth-moving equipment.
6. Bearing soils disturbed by excavating equipment must be recompacted to 95 percent of
maximum Standard Proctor Density (ASTM D698) prior to placing concrete.
7. Exposed areas which will receive fill once properly cleaned, shall be scarified to a mini-
mum depth of 8-inches, conditioned to near optimum moisture content, and compacted.
B. Classified Excavation: Excavate to subgrade elevations. Material to be excavated will be
classified as earth excavation and rock excavation. Do not excavate rock until it has been
classified and cross sectioned by Owner’s Representative.
1. Earth excavation includes excavating pavements and obstructions visible on surface;
underground structures, utilities, and other items indicated to be removed; together with
soil, boulders, and other materials not classified as rock or unauthorized excavation.
a. Intermittent drilling; ram hammering; or ripping of material not classified as rock
excavation is earth excavation.
C. Stability:
1. Slope sides of excavations in compliance with OSHA requirements and local codes or
ordinances. Shore and brace where sloping is not possible because of space restrictions
or stability of material excavated.
2. Continuously monitor cut slopes for distress. Take all necessary precautions to safeguard
workers, structures, and utilities.
3. Provide all necessary shoring, sheeting, or bracing of sides of excavations required to
prevent caving, erosion, and gullying. Provide underpinning of existing structures or
other improvements adjacent to excavations which are subject to damage.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-9
D. Unanticipated Conditions: Notify the Owner’s Representative immediately upon finding
evidence of previous structures or filled materials which penetrate below designated excavation
levels, groundwater or water-bearing strata, or other conditions which are not shown or which
cannot be reasonably assumed from existing surveys and geotechnical reports. Secure the
Owner’s Represenative instruction before proceeding with further work in such areas.
E. Rock Excavation: Includes removal and disposal of rock. Remove rock to lines and subgrade
elevations indicated to permit installation of permanent construction. Rock excavation in
unconfined areas is defined as removal and disposal of material which in the Geotechnical
Engineer’s opinion, cannot be excavated without continuous and systematic drilling and
blasting, or continuous use of a suitable ripper or other special equipment.
1. Unanticipated Rock Excavation: Rock excavation that is not indicated on existing
surveys or which cannot be reasonably assumed from geotechnical studies of the site and
which could not have been anticipated without extensive investigations. Unanticipated
rock excavation shall be subject to change order procedures or previously agreed upon
unit prices.
3.5 EXCAVATION FOR STRUCTURES
A. Excavate to indicated elevations and dimensions within a tolerance of plus or minus 0.10-foot.
If applicable, extend excavations a sufficient distance from structures for placing and removing
concrete formwork, for installing services and other construction, and for inspections.
1. Excavations for Footings and Foundations: Do not disturb bottom of excavation.
Excavate by hand to final grade just before placing concrete reinforcement. Trim
bottoms to required lines and grades to leave solid base to receive other work.
2. Excavation for Underground Tanks, Basins, and Mechanical or Electrical Utility
Structures: Excavate to elevations and dimensions indicated within a tolerance of plus or
minus 1 inch (25 mm). Do not disturb bottom of excavations intended as bearing
surfaces.
3. Excavation Below Slab on Grade, or Walks, or Pavement: Overexcavate clays and
claystone within the proposed footprint of the building slab-on-grade to a minimum
depth as recommended in Geotech Report and replace with on-site or imported materials
as approved by Geotechnical Engineer.
B. Existing man-made fill shall be removed under structures as required by the Geotechnical
Engineer.
3.6 EXCAVATION FOR WALKS AND PAVEMENTS
A. Excavate surfaces under walks and pavements to indicated lines, cross sections, elevations, and
subgrades.
B. Scarify subgrade soils beneath exterior slabs, sidewalks and pavements to a minimum depth of
8-inches, moisture condition and recompact as specified.
C. Existing man-made fill shall be removed under walks and pavements as required by the
Geotechnical Engineer.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-10
3.7 EXCAVATION FOR UTILITY TRENCHES
A. Refer to Division 31 Section “Trenching and Backfilling,” for excavating and backfilling of
utilities.
3.8 SUBGRADE INSPECTION
A. Notify Geotechnical Engineer when excavations have reached required subgrade.
B. If Owner’s Representative and Geotechnical Consultant determines that unsatisfactory soil is
present, continue excavation and replace with compacted backfill or fill material as directed.
C. Proof-roll subgrade below the building slabs and pavements with heavy pneumatic-tired
equipment to identify soft pockets and areas of excess yielding. Remove and replace soft
areas. Do not proof-roll wet or saturated subgrades.
1. Completely proof-roll subgrade in one direction, repeating proof-rolling in direction
perpendicular to first direction. Limit vehicle speed to 3 mph (5 km/h).
2. Proof-roll with a loaded 10-wheel, tandem-axle dump truck weighing not less than 15
tons.
3. Excavate soft spots, unsatisfactory soils, and areas of excessive pumping or rutting, as
determined by Owner’s Representative, and replace with compacted backfill or fill as
directed.
D. Authorized additional excavation and replacement material will be paid for according to
Contract provisions for changes in the Work.
E. Reconstruct subgrades damaged by freezing temperatures, frost, rain, accumulated water, or
construction activities, as directed by Owner’s Representative, without additional
compensation.
3.9 UNAUTHORIZED EXCAVATION
A. Fill unauthorized excavation under foundations or wall footings by extending bottom elevation
of concrete foundation or footing to excavation bottom, without altering top elevation. Lean
concrete fill, with 28-day compressive strength of 2500 psi (17.2 MPa), may be used when
approved by Geotechnical Engineer. If approved by Geotechnical Engineer, structural fill
placed at 100 percent ASTM D698, 2 percent below to 1 percent above optimum moisture may
be used.
1. Fill unauthorized excavations under other construction or utility pipe as directed by
Owner’s Representative.
3.10 STORAGE OF SOIL MATERIALS
A. Stockpile borrow soil materials and excavated satisfactory soil materials in approved locations
without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to
prevent windblown dust.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-11
1. Stockpile soil materials away from edge of excavations. Do not store within drip line of
remaining trees.
3.11 BACKFILL
A. Place and compact backfill in excavations promptly, but not before completing the following:
1. Construction below finish grade including, where applicable, subdrainage, dampproofing,
waterproofing, and perimeter insulation.
2. Surveying locations of underground utilities for Record Documents.
3. Testing and inspecting underground utilities.
4. Removing concrete formwork.
5. Removing trash and debris.
6. Removing temporary shoring and bracing, and sheeting.
7. Installing permanent or temporary horizontal bracing on horizontally supported walls.
8. Acceptance of subgrade by Geotechnical Engineer.
B. Place backfill on subgrades free of mud, frost, snow, or ice.
3.12 UTILITY TRENCH BACKFILL
A. Refer to Division 31 Section “Trenching and Backfilling,” for excavating and backfilling of
utilities.
3.13 SOIL FILL
A. Preparation: Remove vegetation, topsoil, debris, unsatisfactory soil materials, obstructions, and
deleterious materials from ground surface before placing fills.
1. Plow, scarify, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so
fill material will bond with existing material.
2. In areas of fill, scarify natural soil following removal of unsatisfactory material, to a
depth of 8-inches.
B. Place and compact fill material in layers to required elevations per the geotechnical report and
as follows:
1. Under grass and planted areas, use satisfactory soil material.
2. Under walks and pavements, use satisfactory soil material.
3. Under steps and ramps, use engineered fill or structural fill as approved by Geotechnical
Engineer.
4. Under building slabs, use engineered fill or reconditioned on-site soils or imported fills of
native soils as approved by Geotechnical Engineer.
5. Under footings and foundations, use engineered fill or reconditioned on-site soils or
imported fills of native soils as approved by Geotechnical Engineer.
C. Place soil fill on subgrades free of mud, frost, snow, or ice.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-12
3.14 SOIL MOISTURE CONTROL
A. Uniformly moisten or aerate subgrade and each subsequent fill or backfill soil layer before
compaction to optimum or to 3 percent over optimum moisture content for clay soils, or within
2 percent of optimum moisture content for granular soils. Refer to geotechnical study for
additional recommendations.
1. Do not place backfill or fill soil material on surfaces that are muddy, frozen, or contain
frost or ice.
2. Remove and replace, or scarify and air dry otherwise satisfactory soil material that
exceeds optimum moisture content beyond the tolerances described above and is too wet
to compact to specified dry unit weight.
3.15 COMPACTION OF SOIL BACKFILLS AND FILLS
A. Place backfill and fill soil materials in layers not more than 8 inches (200 mm) in loose depth
for material compacted by heavy compaction equipment, and not more than 4 inches (100 mm)
in loose depth for material compacted by hand-operated tampers.
B. Place backfill and fill soil materials evenly on all sides of structures to required elevations, and
uniformly along the full length of each structure.
C. Compact soil materials to not less than the following percentages of maximum dry unit weight
according to ASTM D 698:
1. Under exterior flatwork, slabs, steps, and pavements, scarify and recompact top 8 inches
(300 mm) of existing subgrade and each layer of backfill or fill soil material at 95
percent.
2. Under footings and interior floor slabs, excavate to approved natural soils, in fill
condition, compact to 95 percent.
3. Under lawn or unpaved areas, scarify and recompact top 6 inches (150 mm) below
subgrade and compact each layer of backfill or fill soil material at 90 percent.
4. Compact foundation wall backfill to 95 percent.
5. Compact scarified subgrade soils to 95 percent.
6. Compact retaining wall backfill to 95 percent.
3.16 GRADING
A. General: Uniformly grade areas to a smooth surface, free of irregular surface changes. Comply
with compaction requirements and grade to cross sections, lines, and elevations indicated.
1. Provide a smooth transition between adjacent existing grades and new grades.
2. Cut out soft spots, fill low spots, and trim high spots to comply with required surface
tolerances.
B. Site Grading: Slope grades to direct water away from buildings and to prevent ponding. Finish
subgrades to required elevations within the following tolerances:
1. Lawn or Unpaved Areas: Plus or minus 0.10 feet.
2. Walks: Plus or minus 0.10 feet.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-13
3. Pavements: Plus or minus 0.10 feet.
4. Grading inside Building Lines: Finish subgrade to a tolerance of ½-inch (13 mm) when
tested with a 10-foot (3-m) straightedge.
3.17 SUBBASE AND BASE COURSES
A. Place subbase and base course on subgrades free of mud, frost, snow, or ice.
B. On prepared subgrade, place subbase and base course under pavements and walks as follows:
1. Install separation geotextile, if requested by Geotechnical Engineer, on prepared subgrade
according to manufacturer's written instructions, overlapping sides and ends.
2. Place base course material over subbase course under hot-mix asphalt pavement.
3. Shape subbase and base course to required crown elevations and cross-slope grades.
4. Place subbase and base course 6 inches (150 mm) or less in compacted thickness in a
single layer.
5. Place subbase and base course that exceeds 6 inches (150 mm) in compacted thickness in
layers of equal thickness, with no compacted layer more than 6 inches (150 mm) thick or
less than 3 inches (75 mm) thick.
6. Compact subbase and base course at optimum moisture content to required grades, lines,
cross sections, and thickness to not less than 95 percent of maximum dry unit weight
according to ASTM D 698.
C. Pavement Shoulders: Place shoulders along edges of subbase and base course to prevent lateral
movement. Construct shoulders, at least 12 inches (300 mm) wide, of satisfactory soil
materials and compact simultaneously with each subbase and base layer to not less than 95
percent of maximum dry unit weight according to ASTM D 698.
3.18 DRAINAGE COURSE
A. Place drainage course on subgrades free of mud, frost, snow, or ice.
B. On prepared subgrade, place and compact drainage course under cast-in-place concrete slabs-
on-grade as follows:
1. Install subdrainage geotextile if required by Geotechnical Engineer on prepared subgrade
according to manufacturer's written instructions, overlapping sides and ends.
2. Place drainage course 6 inches (150 mm) or less in compacted thickness in a single layer.
3. Place drainage course that exceeds 6 inches (150 mm) in compacted thickness in layers of
equal thickness, with no compacted layer more than 6 inches (150 mm) thick or less than
3 inches (75 mm) thick.
4. Compact each layer of drainage course to required cross sections and thicknesses to not
less than 95 percent of maximum dry unit weight according to ASTM D 698.
3.19 FIELD QUALITY CONTROL
A. Testing Agency: Project Owner will engage a qualified independent geotechnical engineering
testing agency to perform field quality-control testing.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
EARTH MOVING 31 2000-14
B. Allow testing agency to inspect and test subgrades and each fill or backfill layer. Proceed with
subsequent earth moving only after test results for previously completed work comply with
requirements.
C. Footing Subgrade: At footing subgrades, at least one test of each soil stratum will be performed
to verify design bearing capacities. Subsequent verification and approval of other footing
subgrades may be based on a visual comparison of subgrade with tested subgrade when
approved by Owner’s Representative.
D. Testing agency will test compaction of soils in place according to ASTM D 1556,
ASTM D 2167, ASTM D 2922, and ASTM D 2937, as applicable. Perform field moisture tests
in accordance with ASTM D3017. Tests will be performed at the following locations and
frequencies at a minimum:
1. Paved and Building Slab Areas: At subgrade and at each compacted fill and backfill
layer, at least 1 test for every 2000 sq. ft. (186 sq. m) or less of paved area or building
slab, but in no case fewer than 3 tests.
2. Foundation Wall Backfill: At each compacted backfill layer, at least 1 test for each 100
feet (30 m) or less of wall length, but no fewer than 2 tests.
E. When testing agency reports that subgrades, fills, or backfills have not achieved degree of
compaction specified, scarify and moisten or aerate, or remove and replace soil to depth
required; recompact and retest until specified compaction is obtained.
3.20 PROTECTION
A. Protecting Graded Areas: Protect newly graded areas from traffic, freezing, and erosion. Keep
free of trash and debris.
B. Repair and reestablish grades to specified tolerances where completed or partially completed
surfaces become eroded, rutted, settled, or where they lose compaction due to subsequent
construction operations or weather conditions.
1. Scarify or remove and replace soil material to depth as directed by Owner’s
Representative; reshape and recompact.
C. Where settling occurs before Project correction period elapses, remove finished surfacing,
backfill with additional soil material, compact, and reconstruct surfacing.
1. Restore appearance, quality, and condition of finished surfacing to match adjacent work,
and eliminate evidence of restoration to greatest extent possible.
3.21 DISPOSAL OF SURPLUS AND WASTE MATERIALS
A. Disposal: Remove surplus satisfactory soil and waste material, including unsatisfactory soil,
trash, and debris, and legally dispose of it off Owner's property.
END OF SECTION 31 2000
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-1
SECTION 31 2333 – TRENCHING AND BACKFILLING
PART 1 - GENERAL
1.1 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract, including General and Supplementary
Conditions and Division 1 Specification Sections, apply if provided, to this Section.
B. Additional information concerning trenching and backfilling may be found on the civil
drawings, in the project geotechnical study/report and Town of Vail Development standards. In
case of conflict between the drawings, jurisdictional criteria and the information specified
herein, the more stringent requirements shall govern.
C. Additional information concerning earthwork may be found in the geotechnical investigation
report by < > dated < >. All requirements of
this report shall be followed unless noted otherwise. The information shown in this report is for
information and it shall be the Contractor’s responsibility to field verify conditions indicated.
1.2 SUMMARY
A. This Section includes the following:
1. Subsurface drainage backfill for walls and trenches.
2. Excavating and backfilling for utility trenches.
3. Excavating and backfilling trenches for buried mechanical and electrical utilities and pits
for buried utility structures.
4. Excavating and backfilling trenches within building lines.
B. Related Sections include the following:
1. Division 31 Section "Site Clearing" for site stripping, grubbing, stripping and stockpiling
topsoil, and removal of above- and below-grade improvements and utilities.
2. Division 33 Section “Subdrainage Systems” for drainage of foundations, slabs-on-grade,
walls, and landscaped areas.
3. Division 31 Section “Earth Moving” for soil materials, site excavating, filling and
grading.
4. Division 31 Section “Temporary Erosion and Sedimentation Control” for erosion and
sediment control.
5. Divisions 22, and 26 Sections for installing underground mechanical and electrical
utilities and buried mechanical and electrical structures, if available.
6. Division 33 Section “Water Utility Distribution Piping” for water main installation.
7. Division 33 Section “Storm Utility Drainage Piping” for storm sewer system installation.
8. Division 33 Section “Sanitary Utility Sewerage Piping” for sanitary sewer main
installation.
C. Shoring Design: Provide the services of a professional engineer to design all shoring, bracing,
and underpinning required to protect the safety of workers and integrity of adjacent existing
structures or other improvements.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-2
1.3 DEFINITIONS
A. Backfill: Soil material or controlled low-strength material used to fill an excavation.
1. Initial Backfill: Backfill placed beside and over pipe in a trench, including haunches to
support sides of pipe.
2. Final Backfill: Backfill placed over initial backfill to fill a trench.
B. Base Course: Course placed between the subbase course and hot-mix asphalt paving.
C. Bedding Course: Course placed over the excavated subgrade in a trench before laying pipe.
D. Borrow Soil: Satisfactory soil imported from off-site for use as backfill approved by
Geotechnical Engineer.
E. Unclassified Excavation: Removal of all material of whatever-character required for the work
encountered above subgrade elevations and to lines and dimensions indicated, including
boulders.
F. Authorized Additional Excavation: Excavation below subgrade elevations or beyond indicated
lines and dimensions as directed or approved by Owner’s Representative and the testing and
inspections agency to correct unsatisfactory conditions. Authorized additional excavation and
replacement material will be paid for according to Contract provisions for changes in the Work.
G. Bulk Excavation: Excavation more than 10 feet (3 m) in width and more than 30 feet (9 m) in
length.
H. Unauthorized Excavation: Excavation below subgrade elevations or beyond indicated lines and
dimensions without direction by Owner’s Representative. Unauthorized excavation including
disposition of overexcavated materials and other work resulting from slides, cave-ins, swelling,
upheaval, or remedial work, as well as remedial work directed by Owner’s Representative, shall
be without additional compensation.
I. Rock Excavation: Rock material in beds, ledges, unstratified masses, conglomerate deposits,
and boulders of rock material that exceed 1 cu. yd. (0.76 cu. m) for bulk excavation or 3/4 cu.
yd. (0.57 cu. m) for footing, trench, and pit excavation that cannot be removed by rock
excavating equipment equivalent to the following in size and performance ratings, without
systematic drilling, ram hammering, ripping, or blasting, when permitted:
1. Excavation of Footings, Trenches, and Pits: Late-model, track-mounted hydraulic
excavator; equipped with a 42-inch- (1065-mm-) wide, maximum, short-tip-radius rock
bucket; rated at not less than 138-hp (103-kW) flywheel power with bucket-curling force
of not less than 28,090 lbf (125 kN) and stick-crowd force of not less than 18,650 lbf (83
kN); measured according to SAE J-1179.
2. Bulk Excavation: Late-model, track-mounted loader; rated at not less than 210-hp (157-
kW) flywheel power and developing a minimum of 48,510-lbf (216-kN) breakout force
with a general-purpose bare bucket; measured according to SAE J-732.
J. Subbase Course: Course placed between the subgrade and base course for hot-mix asphalt
pavement, or course placed between the subgrade and a cement concrete pavement or a cement
concrete or hot-mix asphalt walk.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-3
K. Subgrade: Surface or elevation remaining after completing excavation, or top surface of a fill or
backfill immediately below subbase, drainage fill, or topsoil materials.
L. Utilities: Includes on-site underground pipes, conduits, ducts, and cables, as well as
underground services within buildings.
M. Controlled Low Strength Material (CLSM): Controlled Low Strength Materials (CLSM)
consists of a well-graded mixture of mineral aggregates, cementitious materials, water and
admixtures. Other common names for CLSMs include: flowable fill, flowfill, non-shrink
backfill, fly ash fill and controlled density fill.
1.4 SUBMITTALS
A. Product Data: For the following:
1. Each type of plastic warning tape.
B. Samples: Contractor to submit representative samples of all materials proposed for use in
bedding and trench backfilling operations to the testing and inspections agency for analysis and
determination of compliance with the requirements specified herein.
C. Material Test Reports: Provided by Project Owner from a qualified testing agency indicating
and interpreting test results for compliance of the following with requirements indicated:
1. Classification according to ASTM D 2487 of each on-site or borrow soil material
proposed for fill and backfill.
2. Laboratory compaction curve according to ASTM D 698 for each on-site or borrow soil
material proposed for fill and backfill.
D. Pre-Excavation Photographs or Videotape: Show existing conditions of adjoining construction
and site improvements, including finish surfaces that might be misconstrued as damage caused
by earthwork operations. Submit before earthwork begins.
E. CLSM: The Contractor will be required to submit a mix design and test data for approval, prior
to excavating the area for which CLSMs are proposed for use. All materials of this category
placed without previous approval, or which do not perform as specified, will be rejected by the
Owner and all costs incurred for removal and replacement of these materials will be at the
Contractor’s expense.
1.5 QUALITY ASSURANCE
A. Testing Agency:
1. All testing and inspections required herein will be performed by an independent testing
and inspection agency employed by the Project Owner.
2. Notify the testing and inspection agency not less than 48 hours in advance of all work re-
quiring testing or inspection services.
B. Regulatory Requirements: Comply with all applicable requirements of the Occupational Safety
and Health Administration and local and State rules, regulations, and ordinances concerning
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-4
shoring, bracing, or sloping of excavations and safety of workers. Safety of workers is the re-
sponsibility of the Contractor.
C. Coordination: Coordinate scheduling and procedures for trench excavation, bedding, and back-
filling with other Sections whose work relates to or is affected by this work.
D. Pre-Construction Conference: Conduct conference at Project site as directed by Owner’s
Representative prior to start of construction. Contractor to comply with requirements, which
also may be included in Division 1 Section "Project Management and Coordination."
1.6 PROJECT CONDITIONS
A. Existing Utilities: Locations, sizes and depths or invert elevations of existing utilities as shown
on the drawings are based on information provided by others, and are believed to be correct, but
may not be absolutely so. Such information is therefore presumed only as approximations and
should be verified prior to construction. Do not interrupt utilities serving facilities occupied by
Owner or others unless permitted in writing by Owner’s Representative and then only after
arranging to provide temporary utility services according to requirements indicated.
1. Notify Owner’s Representative not less than two (2) days in advance of proposed utility
interruptions.
2. Do not proceed with utility interruptions without Owner’s Representative's written
permission.
3. Contact utility-locator service for area where Project is located before excavating.
B. Demolish and completely remove from site existing underground utilities indicated to be
removed. Coordinate with utility companies to shut off services if lines are active.
C. Existing Benchmarks: Carefully preserve and maintain existing bench marks, monuments,
property line pins, and other reference points. If disturbed or destroyed, restore or replace them
by a registered Colorado Professional Land Surveyor at no additional cost to the Project Owner.
D. Verification of Existing Conditions: Visit the site prior to submission of bids. Verify existing
conditions, elevations, and utility locations. In the event of discrepancies between existing
conditions and those indicated on the Contract Documents or survey, contact the Owner’s
Representative for clarification.
1.7 WARRANTY
Settlement in backfill, fill or in structures built over backfill or fill, which may occur within the
specified project warranty period, shall be corrected at no cost to the Project Owner. Any struc-
tures damaged by settlement shall be restored to their original condition by the Contractor, at no
cost to the Project Owner.
PART 2 - PRODUCTS
2.1 MATERIALS
A. Utility Trench Bedding Materials:
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-5
1. Granular Bedding: Well graded mixture of sound mineral aggregate complying with
Class 67 (Modified) gradation in accordance with the following table:
Class 67 (Modified) Gradation
Nominal Size Percent Passing by Weight
¾” 90-100
3/8” 20-55
No. 4 5-10
No. 8 5-10
In the event the excavation or overexcavation for bedding is below the water table, the
sub-bedding material shall consist of ¾-inches to 1-1/2-inches rock (or larger if ap-
proved), placed in accordance with the Agency have authority .
2. Sand Bedding: Clean, well-graded sand, not more than 5% by weight passing a No. 200
sieve.
B. Utility Trench Backfill Materials:
1. Existing soils obtained from trench excavations, including granular or aggregate base
course from removed pavements, broken and pulverized claystone or claystone-sandstone
bedrock may be used for backfilling trenches, provided it meets any special requirements
of the Utility Agency and Geotechnical Engineer. Bedrock must be processed and bro-
ken or pulverized so that the maximum particle or fragment size does not exceed three-
inches (3-inches).
C. Unsuitable Utility Trench Materials: Materials unsuitable for bedding and backfilling include
highly organic soils, ASTM D2487 Group PT topsoil, and soils containing roots, vegetable
matter, trash, and debris.
2.2 CONTROLLED LOW STRENGTH MATERIAL (CLSM)
A. Controlled Low Strength Material: Self compacting, flowable concrete material produced from
the following:
1. Portland Cement: ASTM C 150, Type II minimum 50 lbs/cu. yd. Per CDOT Standard
Specifications Section 206.
2. Fly Ash: ASTM C618, Class C or F. Can be substituted up to 40% of weight of Portland
Cement.
3. Coarse Aggregate: In accordance with the grading and quality requirements of ASTM C
33 for Size No. 467, No. 57, or No. 67.
4. Fine Aggregate: In accordance with the grading and quality requirements of ASTM C33.
5. Foaming Agent: ASTM C 869.
6. Water: ASTM C94/C 94 M.
7. Air-Entraining Admixture: ASTM C 260.
8. Admixtures: Admixtures that do not contain calcium chloride and are in accordance with
ASTM C 494 for concrete may be used. Admixtures shall be compatible with the cement
and other admixtures.
B. Produce low-density, controlled low strength material with the following physical properties:
1. Total cementitious material: 50 to 95 lb/cy.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-6
2. Fly Ash by Weight: Maximum 40% of total cementitious materials.
3. Air-entrained to total air content: 4% to 8%.
4. The mix shall have a slump between 7 and 10 inches as per AASHTO Designation T
119-82 or ASTM C 143.
5. Fine Aggregates: Between 50% and 60% by volume of total aggregate.
6. Compressive strength at 28 days: 50 to 150 psi when molded and cured in accordance
with ASTM D 4832.
7. Maximum water-cement ration: 3.5:1.
2.3 ACCESSORIES
A. Shoring and Bracing: Provide all materials for shoring and bracing, such as sheet piling,
uprights, stringers, and cross-braces, in good and serviceable condition, as required for safety
and by governing authorities.
B. Detectable Warning Tape: Acid- and alkali-resistant polyethylene film warning tape
manufactured for marking and identifying underground utilities, a minimum of 6 inches (150
mm) wide and 4 mils (0.1 mm) thick, continuously inscribed with a description of the utility;
colored as follows:
1. Red: Electric.
2. Yellow: Gas, oil, steam, and dangerous materials.
3. Orange: Telephone and other communications.
4. Blue: Water systems.
5. Green: Sewer systems.
PART 3 - EXECUTION
3.1 EXAMINATION
A. Verification of Conditions: Examine areas and conditions under which the work of this Section
will be performed. Do not proceed with the work until unsatisfactory conditions have been cor-
rected. Commencement of work implies acceptance of all areas and conditions.
3.2 PREPARATION
A. Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by
settlement, lateral movement, undermining, washout, and other hazards created by earthwork
operations.
B. Preparation of subgrade for earthwork operations including removal of vegetation, topsoil,
debris, obstructions, and deleterious materials from ground surface is specified in Division 31
Section "Site Clearing."
C. Protect and maintain erosion and sedimentation controls, which are specified in Division 31
Section "Temporary Erosion and Sediment Control," during earthwork operations.
D. Existing Utilities:
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-7
1. General: Location of existing utilities shown on the plans are approximate only. The
Contractor shall be responsible to locate all existing underground utilities in areas of the
work. If utilities are to remain in place, provide protection during excavation and back-
filling operations. Should uncharted or incorrectly charted piping or other utilities be en-
countered during excavations, consult the Owner’s Representative immediately for direc-
tion. Cooperate with the Utility Agency in keeping respective services and facilities in
operation. Repair damaged utilities to the satisfaction of the Utility Agency.
2. Active Utilities: Do not interrupt existing utilities serving facilities occupied and used by
the Town of Vail or by adjacent properties, except when permitted in writing by the
Owner’s Representative, and then only after acceptable temporary utility services have
been provided. Remove or relocate utilities only as indicated or specified.
3. Inactive Utilities: Report inactive or abandoned utilities encountered in excavating or
grading operations, and remove, plug, or cap as required. In the absence of specific re-
quirements, plug or cap such utility lines at least 5-feet -0-inches outside new building
walls, or as required by local requirements.
4. Removal: Demolish and completely remove from the project site all existing under-
ground utilities indicated to be removed. Coordinate with Utility Agencies for discontin-
uance of services if lines are active.
E. Protection of Persons and Property:
1. Provide all necessary measures to protect workmen and passersby. Barricade open exca-
vations occurring as part of the work, as required by municipal or other authorities having
jurisdiction.
2. Protect adjacent streets, structures, and other improvements from damage caused by set-
tlement, undermining, washout, and other hazards created by trench excavations.
F. Protect subgrades and trench bottoms soils against freezing temperatures or frost. Provide
protective insulating materials as necessary.
G. Cold Weather Work: Prevent frost from entering bearing strata upon which construction will
taken place or in areas where fill will be placed in that season.
3.3 DEWATERING
A. Prevent surface water and subsurface or ground water from entering excavations, from ponding
on prepared subgrades, and from flooding Project site and surrounding area.
B. Provide and maintain pumps, well points, sumps, suction and discharge lines, and other
dewatering system components necessary to convey water away from excavations and to
collection or runoff areas. Establish and maintain temporary drainage ditches and diversions
away from trench excavations. Do not use trench excavations as temporary drainage ditches.
C. Protect subgrades from softening, undermining, washout, and damage by rain or water
accumulation.
1. Reroute surface water runoff away from excavated areas. Do not allow water to
accumulate in excavations. Do not use excavated trenches as temporary drainage ditches.
2. Install a dewatering system to keep subgrades dry and convey ground water away from
excavations. Maintain until dewatering is no longer required.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-8
3. Obtain and comply with all provisions of the Colorado Department of Public Health and
Environment, Water Quality Control Division, Construction Dewatering Permit.
3.4 SHORING AND BRACING
A. Provide shoring and bracing of excavations as required for safety and by governing authorities.
Carry down shoring and bracing as excavation progresses. Maintain shoring and bracing in
excavations regardless of time period excavations will be open.
3.5 PAVEMENT REMOVAL AND REPLACEMENT
A. Where trenches or other utility excavations are made in existing paved areas, saw-cut pavement
surface to create a clean break line. Cut pavement a minimum of 12-inches beyond trench
width on each side of trench; remove and dispose of existing surface course and aggregate base
course, leaving a 12-inches wide undisturbed subgrade lip on each side of trench.
B. After trench has been backfilled and compacted, place new pavement in accordance with
applicable requirements of Division 32 Sections as applicable, for Asphaltic or Portland cement
concrete pavement and in accordance with Authorities having jurisdiction.
3.6 EXPLOSIVES
A. Explosives: Do not use explosives.
3.7 EXCAVATION FOR UTILITY TRENCHES
A. Excavate trenches to indicated gradients, lines, depths, and elevations.
1. Beyond building perimeter, excavate trenches to allow installation of top of pipe below
frost line.
B. Excavate trenches to uniform widths to provide the following clearance on each side of pipe or
conduit. Excavate trench walls vertically from trench bottom to 12 inches (300 mm) higher
than top of pipe or conduit, unless otherwise indicated on the drawings.
C. Clearance: 12 inches (300 mm) each side of pipe or conduit.
1. Slope sides of trenches or provide shoulders in accordance with OSHA requirements and
as required by Utility Agency standards.
2. Continuously monitor cut slopes and trenches for distress or movement. Provide all
necessary shoring and bracing required to protect the life and safety of workmen
performing excavation or installing piping or conduit.
D. Trench Bottoms: Excavate trenches a minimum of 3 inches (75 mm) deeper than bottom of
pipe elevation to allow for bedding course. Hand excavate for bell of pipe.
1. Excavate trenches 6 inches (150 mm) deeper than elevation required in rock or other
unyielding bearing material to allow for bedding course and backfill with a 6-inches layer
of crushed stone or gravel prior to installing pipe.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-9
3.8 BEDDING OF PIPES:
A. After completion of trench excavation and before installation of piping, install not less than 3-
inches of approved bedding material in trench bottom for support of pipe. Dig bell holes in
bedding deep enough to provide a minimum of 2-inches clearance between the bell and bedding
material. Fully support pipe on bedding material for the full length of the pipe barrel.
B. After pipe is adjusted for line and grade, and all jointing is complete, carefully place and tamp
bedding material under the haunches of the pipe and in the previously dug bell holes.
C. Install bedding to a minimum depth of 12-inches above top of pipe prior to starting placement
of compacted backfill. Lightly compact or tamp bedding material in a manner to avoid
displacement of or damage to the pipe.
3.9 STORAGE OF SOIL MATERIALS
A. Stockpile borrow soil materials and excavated satisfactory soil materials in approved locations
without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to
prevent windblown dust.
1. Stockpile soil materials away from edge of excavations. Do not store within drip line of
remaining trees.
3.10 UTILITY TRENCH BACKFILL
A. After installation of utility piping or lines have been completed, locations recorded, trash or
other debris removed from excavations, and bedding placed and approved, backfill promptly as
work and weather conditions permit. Do not backfill trenches until all required pipe system
tests and inspections have been made, unless partial backfilling is required to restrain pipe under
test pressures. Use care in backfilling to avoid damage or displacement of pipe systems.
B. Place backfill on subgrades free of mud, frost, snow, or ice.
C. Place and compact bedding course on trench bottoms and where indicated. Shape bedding
course to provide continuous support for bells, joints, and barrels of pipes and for joints,
fittings, and bodies of conduits.
D. Place backfill materials in layers not more than 8-inches in loose depth for material compacted
by heavy compaction equipment, and not more than 4-inches in loose depth for material
compacted by hand operated tampers. Use hand held tools or compacting devices for trench
backfill, until a minimum compacted thickness of 3-feet -0-inches above top of pipe is achieved.
Mechanical or power compactors may be used thereafter.
E. Before compaction, moisten or aerate each layer of backfill to specifications.
F. Compact each layer to not less than 95% of maximum standard Proctor density (ASTM D698).
Thoroughly compact by means of mechanical tampers areas which cannot be properly
compacted by means of rolling equipment.
G. Backfill to subgrade elevation shown for finish grading, topsoil placement, or paving.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-10
H. Place and compact initial backfill of satisfactory soil, free of particles larger than 1 inch (25
mm) in any dimension, to a height of 12 inches (300 mm) over the utility pipe or conduit.
1. Carefully compact initial backfill under pipe haunches and compact evenly up on both
sides and along the full length of utility piping or conduit to avoid damage or
displacement of piping or conduit. Coordinate backfilling with utilities testing.
I. Backfill voids with satisfactory soil while installing and removing shoring and bracing.
J. Place and compact final backfill of satisfactory soil to final subgrade elevation.
K. Install warning tape directly above utilities, 12 inches (300 mm) below finished grade, and 6
inches (150 mm) below subgrade under pavements and slabs.
L. Controlled Low Strength Material: Place initial backfill of controlled low strength material to a
height of 12 inches (300 mm) over the pipe or conduit. Coordinate backfilling with utilities
testing.
M. Controlled Low Strength Material: Place final backfill of controlled low strength material to
final subgrade elevation.
N. When CLSMs are placed within the right-of-way, or they are to be covered by paving materials,
the final set product must achieve a maximum indentation diameter of 3 inches prior to covering
and opening the area to traffic. Penetration resistance shall be as measured by ASTM C6024,
“Standard Test Method for Ball Drop on Controlled Low Strength Material to Determine
Suitability for Load Application”.
O. CLSM must be placed in a uniform manner that will prevent voids or segregation of the backfill
and shifting of pipelines, structures and appurtenances. Foreign material that falls into the
trench prior to, or during placement shall be immediately removed.
3.11 SUBSURFACE DRAINAGE
A. Subdrainage Pipe: Specified in Division 33 Section "Subdrainage Systems."
B. Subsurface Drain: Place subsurface drainage geotextile around perimeter of subdrainage trench.
Place a 6-inch (150-mm) course of filter material on subsurface drainage geotextile to support
subdrainage pipe. Encase subdrainage pipe in a minimum of 12 inches (300 mm) of filter
material, placed in compacted layers 6 inches (150 mm) thick, and wrap in subsurface drainage
geotextile, overlapping sides and ends at least 6 inches (150 mm).
1. Compact each filter material layer to 85 percent of maximum dry unit weight according
to ASTM D 698.
C. Drainage Backfill: Place and compact filter material over subsurface drain, in width indicated,
to within 12 inches (300 mm) of final subgrade, in compacted layers 6 inches (150 mm) thick.
Overlay drainage backfill with 1 layer of subsurface drainage geotextile, overlapping sides and
ends at least 6 inches (150 mm).
1. Compact each filter material layer to 85 percent of maximum dry unit weight according
to ASTM D 698.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-11
2. Place and compact impervious fill over drainage backfill in 6-inches (150-mm) thick
compacted layers to final subgrade.
3.12 FIELD QUALITY CONTROL
A. Testing Agency: Project Owner will engage a qualified independent geotechnical engineering
testing agency to perform field quality-control testing.
B. Allow testing agency to inspect and test subgrades and each fill or backfill layer. Proceed with
subsequent earthwork only after test results for previously completed work comply with
requirements.
C. Testing agency will test compaction of soils in place according to ASTM D 1556, ASTM D
2167, ASTM D 2922, and ASTM D 2937, as applicable. Perform field moisture tests in
accordance with ASTM D3017. Tests will be performed at the following locations and
frequencies at a minimum:
1. Trench Backfill: The density tests shall be performed during backfilling at specified
depths in the trench to ensure that the required density and moisture is obtained
throughout. For trenches less than 30-inches in depth, density tests shall be taken within
18-inches above the top of pipe or conduit and at the surface/toplift as a minimum. For
trenches greater than 30-inches in depth, density tests shall be taken within 18-inches of
the top of the pipe or conduit, and at 2-foot vertical intervals to the top of the trench with
the final test at the surface/toplift. For utility mains conduct one (1) set of tests per 100
feet of linear trench at specified depths and for service lines conduct one (1) test per
every service line per utility type at specified depths. At a minimum, test intervals and
quantities shall meet or exceed the requirements of the local utility agency.
D. When testing agency reports that backfills have not achieved degree of compaction specified,
scarify and moisten or aerate, or remove and replace soil to depth required; recompact and retest
until specified compaction is obtained.
3.13 PROTECTION
A. Protecting Graded Areas: Protect newly graded areas from traffic, freezing, and erosion. Keep
free of trash and debris.
B. Repair and reestablish grades to specified tolerances where completed or partially completed
surfaces become eroded, rutted, settled, or where they lose compaction due to subsequent
construction operations or weather conditions.
1. Scarify or remove and replace soil material to depth as directed by Owner’s
Representative; reshape and recompact.
C. Where settling occurs before Project correction period elapses, remove finished surfacing,
backfill with additional soil material, compact, and reconstruct surfacing.
1. Restore appearance, quality, and condition of finished surfacing to match adjacent work,
and eliminate evidence of restoration to greatest extent possible.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TRENCHING AND BACKFILLING 31 2333-12
3.14 CLEANING AND ADJUSTMENT
A. Cleanup: Remove excess materials not required for backfilling purposes, including excess
spoil material, accumulated debris, and rubbish from site. Burning of waste material is prohib-
ited.
3.15 RESTORATION
A. Adjacent Improvements: Restore all fences, irrigation ditches, yards, lawns, and other struc-
tures or surfaces to condition equal to or better than before work began.
3.16 DISPOSAL OF SURPLUS AND WASTE MATERIALS
A. Disposal: Remove surplus satisfactory soil and waste material, including unsatisfactory soil,
trash, and debris, and legally dispose of it off Owner's property.
END OF SECTION 31 2333
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-1
SECTION 31 2500 - TEMPORARY EROSION AND SEDIMENTATION CONTROL
PART 1 - GENERAL
1.1 RELATED WORK
A. Drawings and general provisions of the Contract, including General and Supplementary
Conditions and Division 1 Specification Sections, apply to this Section.
B. Additional information concerning temporary erosion and sedimentation control may be found
on the civil drawings and Town of Vail Development standards. In case of conflict between the
drawings, jurisdictional criteria and the information specified herein, the more stringent
requirements shall govern.
C. Additional information concerning erosion may be found in the geotechnical investigation
report by < > dated < >. All requirements of this report
shall be followed unless stated otherwise.
1.2 SUMMARY
A. Work Included. Furnish, install, maintain, and remove temporary erosion and sedimentation
controls as shown on the drawings or specified herein, or as required to complete the work.
B. Related Sections include the following:
1. Division 31 Section "Site Clearing" site stripping, grubbing, stripping and stockpiling
topsoil, and removal of above- and below-grade improvements and utilities.
2. Division 33 Section "Subdrainage" for drainage of foundations, slabs-on-grade, walls,
and landscaped areas.
3. Division 31 Section “Earth Moving” for soil materials, site excavating, filling and
grading.
4. Division 31 Section “Trenching and Backfilling” for excavating and backfilling of
utilities.
C. Permits and Fees: Obtain and pay for all permits and fees required for the work of this section,
including erosion and sediment control and water quality permits required by the authority
having jurisdiction and the Colorado Department of Public Health and Environment, Water
Quality Control Division.
D. Erosion Control: The Erosion and Sedimentation Control Drawings included in the Contract
Documents is the minimum requirement to be implemented. Provide additional control as
necessary to meet applicable local and State criteria.
1.3 DEFINITIONS
A. Backfill: Soil material used to fill an excavation.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-2
1. Initial Backfill: Backfill placed beside and over pipe in a trench, including haunches to
support sides of pipe.
2. Final Backfill: Backfill placed over initial backfill to fill a trench.
B. Unclassified Excavation: Removal of all material of whatever character required for the work
encountered above subgrade elevations and to lines and dimensions indicated, including
boulders.
C. Fill: Fill is all material placed to raise the grade of the site or to backfill excavation, upon which
the Soils Engineer has made sufficient tests and observations to enable him to issue a written
statement that, in his opinion, the fill has been placed and compacted in accordance with the
requirements of these specifications.
D. BMP: Best Management Practice. Erosion and sediment control devices, which may consist of
silt fence, crates, filter fabric, riprap, etc.
E. SWMP: Storm Water Management Plan. Identifies BMPs, which are erosion and sediment
control measures for the project.
F. Structures: Buildings, footings, foundations, retaining walls, slabs, tanks, curbs, mechanical
and electrical appurtenances, or other man-made stationary features constructed above or below
the ground surface.
G. Subgrade: Surface or elevation remaining after completing excavation, or top surface of a fill or
backfill immediately below subbase, drainage fill, or topsoil materials.
H. Utilities: Include on-site underground pipes, conduits, ducts, and cables, as well as
underground services to buildings.
1.4 SUBMITTALS
A. Submittal Procedures: All submittals are to be made to the Owner’s Representative. If
provided refer to Division 1 section “Submittal Procedures.”
B. Product Data: Submit manufacturer’s published descriptive literature and complete
specifications for manufactured products specified herein and utilized on the project.
1. Geotextiles.
2. Erosion Control Fabric.
C. Storm Water Management Plan:
1. The Engineer will prepare a Storm Water Management Plan (SWMP) for use during
construction. The Contractor shall prepare and submit a report addressing erosion and
sediment control measures for all sites with over one acre of disturbed ground.
2. The Contractor is responsible for obtaining all required permits including a General
Permit application for Storm Water Discharges associated with construction activities at
least ten (10) days prior to start of construction. Permits are to be filed with the Colorado
Department of Public Health and Environment, Water Quality Control Division.
3. Contractor shall have the Storm Water Management Plan (SWMP) and report available
on-site at all times.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-3
1.5 QUALITY ASSURANCE:
A. Regulatory Requirements: Comply with applicable local, State and Federal ordinances, rules
and regulations concerning sedimentation control and storm water runoff.
B. In case of conflict between the above codes, regulations, references and standards and these
specifications, the more stringent requirements shall govern.
C. Preconstruction Conference: Conduct conference at Project site as directed by Owner’s
Representative prior to start of construction. Contractor to comply with requirements, which
may also be included in Division 1 Section "Project Management and Coordination."
1.6 PROJECT/SITE CONDITIONS
A. Existing Conditions: Verify all existing conditions affecting the work of this section prior to
submitting bids or proposals. Additional compensation will not be allowed for revisions or
modification of work resulting from failure to verify existing conditions.
1.7 WARRANTY
A. Temporary Erosion and Sediment Control measures shall be maintained until permanent
measures are in place. All damaged, disturbed or devices filled with sediment, which may
occur within the specified project warranty period, shall be corrected at no cost to the Project
Owner. Any devices damaged by erosion or sediment shall be restored to their original
condition by the Contractor, at no cost to the Project Owner.
PART 2 - PRODUCTS
2.1 MATERIALS
A. Erosion and Sedimentation Control Materials: Provide one or more of the following materials,
as shown on the plans or as applicable for site conditions:
1. Sand bags.
2. Silt fences.
3. Rock riprap.
4. Temporary seeding.
5. Biodegradable wood excelsior, straw, or coconut-fiber mat enclosed in a photodegradable
plastic mesh.
6. Biodegradable twisted jute or spun-coir mesh, 0.92 lb/sy minimum, with 50 to 65 percent
open area.
7. Drainage geotextile.
8. Impervious fill.
9. Other materials proposed for use on-site.
PART 3 - EXECUTION
3.1 PREPARATION
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-4
A. General:
1. Determine the existing ground elevations, drainage patterns, and changes to such patterns
during excavation in order to satisfactorily plan and provide materials for adequate
erosion and sediment control devices.
3.2 TEMPORARY EROSION AND SEDIMENTATION CONTROL
A. Provide temporary erosion and sedimentation control measures to prevent soil erosion and
discharge of soil-bearing water runoff or airborne dust to adjacent properties and rights-of-way
according to requirements of authorities having jurisdiction.
B. Inspect, repair, and maintain erosion and sedimentation control measures during construction
until permanent vegetation has been established.
C. Remove erosion and sedimentation controls, and restore and stabilize areas disturbed during
removal.
D. Secure grading permit from agency having jurisdiction prior to commencing grading
operations.
3.3 EXAMINATION
A. Verification of Conditions: Examine areas and conditions under which the work of this section
will be performed. Do not proceed with the work until unsatisfactory conditions have been
corrected. Commencement of work implies acceptance of all areas and conditions.
3.4 INSTALLATION
A. Erosion and Sedimentation Control Devices. Erosion and sedimentation control measures to be
taken during construction include, but are not necessarily limited to the following:
1. Apply soil stabilization within 14 days to all disturbed areas that are to be dormant for a
period longer than 30 calendar days after reaching grade. Stabilize soil with mulch
anchored per criteria of authorities having jurisdiction. Temporarily revegetate areas that
will remain in an interim condition for more than sixty (60) days.
2. Roads and parking areas indicated to be paved may be covered with an appropriate
aggregate base course in lieu of mulch. Temporary mulching or aggregate base course is
not required if final pavement construction will take place within 30 days after grading to
final contours.
3. Soils that will be stockpiled for more than 30 days must be mulched and seeded within 14
days after stockpile construction.
4. Prevent sediment from leaving the project site by installing a silt fence or other BMPs as
indicated on the plans. Protect existing storm inlets adjacent to the site by an approved
gravel filter.
5. Locate stone stabilization pads at all points of vehicular ingress and egress to the
construction site.
6. Provide temporary erosion controls consisting of berms at the top of slopes and
interceptor ditches at ends of berms and at those locations which will eliminate or
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-5
minimize erosion during construction, along with temporary seeding, temporary
diversion, chutes, and down pipes and lining of water courses.
7. Temporary sedimentation controls shall consist of silt dams, traps, silt fence, barriers, and
appurtenances at the top of spoil and borrow area slopes and where runoff water exits the
site.
8. Maintain the available silt holding capacity of silt dams, fence traps and barriers until no
longer needed. The sediment capacity of sediment retainage areas shall be at a minimum,
the capacity shown on the plans in conformance with Urban Drainage Criteria Manual,
Volume 3. Prior to removal, obtain concurrence of the Owner’s Representative and
Engineer.
9. Remove accumulated sediment and debris from a BMP when the sediment level reaches
one-half the height of the BMP, or at any time the sediment or debris adversely impacts
the functioning of the BMP.
10. Remove haybales which have deteriorated and filter stone or cloth which has become
dislodged. Place new haybales and new filter and fence.
11. The erosion/sediment control plan shows the minimum required for the project. If it
becomes apparent that additional controls are necessary, the Engineer shall be notified
and with approval of the Owner’s Representative additional controls shall be installed.
B. Chemicals and Pollutants:
1. Store construction materials and chemicals that could contribute pollutants to the runoff
within an enclosure, container, or dike located around the perimeter of the storage area, to
prevent discharge of these materials into runoff from the construction site.
2. Locate areas used for collection and temporary storage of solid and liquid waste away
from the storm drainage system. Provide covering or fencing as required to prevent
windblown materials; construct perimeter dike to contain liquid runoff. These measures
may not be necessary if materials are immediately placed in covered waste containers.
3. Perform equipment maintenance in designated areas using measures such as drip pans to
control petroleum products spillage.
4. Immediately clean up and properly dispose of spills of construction related materials such
as paints, solvents, or other chemicals.
C. Final Stabilization and Long-Term Management:
1. Final stabilization shall be achieved through permanent vegetation and landscaping after
construction of all buildings and paved surfaces.
2. With approval of the Town of Vail temporary erosion and sediment control measures
may be removed within 30 days after final site stabilization is achieved or after
temporary measures are no longer needed.
D. Inspection and Maintenance: Inspect erosion and sediment control measures weekly during
construction. In addition, inspect all facilities immediately after any significant runoff or
snowmelt which results in runoff. Repair or otherwise mitigate any damage to the erosion and
sediment control facilities at no additional cost to the Project Owner.
3.5 CLEANING
A. Removal of Controls: Remove controls upon completion of that portion of the work for which
controls were furnished. Leave the site and work area in a clean condition.
THE EDUCATION CENTER Project No. 122175.00
AT BETTY FORD ALPINE GARDENS Vail, Colorado
TEMPORARY EROSION AND SEDIMENTATION CONTROL 31 2500-6
END OF SECTION 31 2500