HomeMy WebLinkAboutLIONS RIDGE FILING 1 LOT A1 A2 A3 SKYLIONl#Rry=*l t l^d, 4[ , Az, /.3
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ROBERT W. THOMPSON, INC.CONSULTING ENGINEER
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Geotechnical Investigation
Skylion Project
Lion's RidgeVail, Colorado
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1698
Prepared For:
Mountajn Properties LTDc/o Frasier and Gingery Inc.
2840 South Vallejo Street
Englewood, Colorado 80110Job No.
rTol souTH FEDERAL BLVO. . SL,|TE D . DENVER, COLORAOO AO21S . (3O3) 934.5473
July 1, 1974
Jr.'I' 'l a
TABLE OF CONTENTS
CONCLUS I OIIS I
SCOPE
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PROPOSED CONSTRUCTIOII
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SITE CONDITIONS
2
GEOLOGIC SETTING
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SUBSURFACE CONDITiONS
4
SLOPE STABILITY
6
BUILDING FOUNDATIONS
8
RETAINING WALL DESIGI'I
10
FL00R SLABS
L4
SURFACE DRAINAGE I4
LIMITATIONS
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FIG. 1 - LOCATIONS OF EXPLORATORY BORINGS
FIG. 2 - LOGS OF E,XPLORATORY BORINGS
FIGS. 3 through 6 - GRADATI0N TEST RESULTS
TABLE I - RESISTIVITY TEST RESULTS
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CONCLUS IOI'IS
. 1. Subsurface conditjons at the site consist of a highly
variable thickness of qlacial gravels oven hard ljmestone'
?. Groundwater was not encountered in any of the borings.
3. The average slope of the natural ground surface js about
2,5 horizontal to 1 vertical . Theoretical stabjlity analysis
indjcates the present and the proposed site configuration
will be stable.
4. Extensive retajning wail structures wjll be necessary to
make the desired cuts and maintain site stability. l^le
recommend use of select backfill, drainage b'l ankets be-
hind the walls, and construction of the required retaining
structures complete with backfill prior to building con-
struct ion.
5. Large boul<1ers and hard linestone bedror:k were encountered.
Excavat.ion costs wjll be hiqher than normal . Limiting cuts
wjll result in savings. For presently planned grades, a
boulder and rock excavation quantity should be included in
the bid documents.
6. Ljmjted working room will be a problem for both excavation
and generai contractors'
7. Temporary construction slopes ranging from 1.5 to 1to l to I
(horizontal to vertical) will be safe- Long term cut slopes
should be 2:1. Long term fill slopes constructed with the natural
granular soils w.i ll be stable at 1.5 to l provided the height
of fill does not exceed 12 feet. Fills should be benched into
the exjsting natural sloPe-
g. The proposed buildings should be constructed with snread footin5t
bype foundations.
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SCOPE
This report presents the resurts of a qeotechnical study for the sky-
lion Project to be constructed in the Lion,s Ridge Area, Vail, Colorado.
The report presents a description of the qeneral site geo1o5ry, subsurface
conditions, slope stabirity anaiys'i s, recommended foundation systems, ailowabre
soi l pressures, groundwater condjtions and design and construction criteria
influenced by the subsurface conditions. This report was prepared on the
basis of factual data gathered during the field and laboratory investigation
and our experience in the area.
PROPOSED CONSTRUCTION
l.Je understand that two 3-story wood frame bujidinqs are planned on Lot
A-3. Associated with the proposed buj ldings will be a swirnming pool between
the two buildings, parking on Lot A-3 and the Expected lot to the east of
A-3, and retaining walls above and through the proposed buildings. The park-
ing areas will require cuts ranging fron rz to zOt feet. The buildings are
general'ly in a cut section rlith the maximum cut in the buildinq area of
about 12 feet.
SITE CONDITIONS
Lot A-3 and the Excepted lot to the northeast of Lot A-3 are generally
located northwest of Red sandstone creek and north of Interstate 70 within
the Lion's Ridge area, vair, cororado. The site is rocated directly northwest
of sandstone Drive vrhich leads into the Red sandstone creek Road.
The site lies on a moderate to steeply sioping south facing slope. The
natural slope averages about 2.5 to 1 (horfzontal to vertical). The site was
undeveloped with a fair)y even slope across the site. There was a srnall area
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at the southern linrits of the property which had been excavated for gravel .
The southern and southeastern limjts of the property border Sandstone Drive
which has been constructed as a cut and fill section. Along the southeastern
limits of the Excepted lot east of Lot A-3 there is a cut slope approximateiy
20 feet high which is standing on a 1,5 to i (horizontai to vertical) slope.
Generally to the northeast and the southwest, the hjllsjde is regular and
continuous as it'i s within the investigated 1ot. Above the investigated
Lot A-3 and Excepted lot there fs an area shown on Fr'g. 1, Location of Ex-
p'l oratory Borings, as the Lion's Ridge Loop which is an undeveloped road
easement. This area was stripped of vegetation in the past but had been
overgrown by grass and small shrubs.
At the time of our investigatjon, there was no development on site.
During our investjglation rough construction roads were developerd on the site
to provide access for driliing equ'i pment. Development within the area but
not within the limits of the investigated site includes underground water,
sewer, electrical and telephone lines wjthjn the easements of Sandstone Drjve
and overhead transmission'l 'i nes along the Lion's Ridge Loop easement to the
north-northlvest of the investiqated site.
GEOLOGIC SETTING
The investigated site lies wr'thjn the g1acia11y formed Vai l Va11ey.
This site is on the limjts of the val1ey wal.l s r.rhich are generally moderate
to steep in slope. The entire site js below the upper limits of glacial
actjvity along the north-northlvest sjde of the va11ey. The entjre surface
rvithin the site indicates glacial materjals. There are outcrops of sedimen-
tary formations located higher on the slope above the jnvestigated site and
to the vrest and southwest at elevations continuous with elevations in the
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investigated site. Generally the formatjons vrhich occur h.i gher above the
investigated site are the bright red congolomerate, sandstone and siltstone
of the Pennsylvanian and Permian Maroon Formation. To the west-southwest
at elevations equ'i va] ent to those found vrithin the investigated site are
interbedded ljmestones and shales of the Pennsylvania and Permian Minturn
Formatjon. samples of the bedrock encountered during the driiling phase of
our jnvestigation were of red, pink, and gray limestones, sandstones, and
shales indicat'i ng that underiying the surface glacial overburden is bedrock
of the Maroon and Minturn Formations. 0utcrops within the general area had
att'i tudes ranging in strike from N60E to N82E and dips to the northwest ranging
fron 20 to 32 degrees. The dip of the sedimentary formations is opposite to
the slope of the vailey. The natural valley walls are a rever,se slope to the
sedimentary formatjons. Bedding plane slippage does not appear possible.
There are no topographical or vegetational indications that there is
any subsurface water aiong the slope on which this site is located. we
believe that the majority of rainwater and snow melt is carried as surface
water due to the steepness in slope.
SUBSURFACE CONDITIONS
subsurface conditions were investigated by driliing 6 borings at the
locations indicated on Fig. 1, Locations of Exploratory Borings. The
borings vrere attempted wjth a 4 inch continuous flight power auger at the
location of Test Hole No. 1, but it was not possible because of the'l arge
cobbles and boulders. The exploratory borings were drilled with a 4 inch
diameter down-the-hole air percussion hammer powered by a cME 55 drjll rig
and a 500 CFl4 ajr compressor. When the upper overburden material of boulders
and gravei uras penetrated, the bedrock was rotary drilled with either a
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"drag bit" or "roller bit" or NX sized diamond tipped core barrel using
air to remove cuttings from the borings.
Generaliy two types of subsurface materials were encountered in the
borings as shown on the Logs of Exploratory Borings, Fig. 2. The two
generalized subsurface units were (1) glacial debris which consisted of
boulders and cobble gravelly sandy matrix; these soils were medium dense
to dense, moist and gray to reddish brown, (z) weathered bedrock and bedrock
which included interbedded shale, sandstone and limestone. The bedrock was
primarily a very hard gray limestone interbedded with thinner beds of shale,
sjltstone and sandstone which were also very hard. Both the overlying glacial
maberial and bedrock layers vary considerably in thickness. The depth to
bedrock was very erratic and ranged from 9 to 80t feet. As indicated by the
Logs of Exploratory Holes, Fig. 2, the bedrock surface is near the ground
surface at rH-6 (elevation 9298) and slopes moderately to the east to the
location of rH-? and rH-5 where the bedrock surface begins to slope steeply
to the east. Bedrock was not encountered in Test Holes l and 4 to depths
of 45 feet. l,le investigated the depth to the bedrock surface at rH-l and
TH-4 using electrical resjstivity equipment whjch indicated that bedrock
uras approximately 70 to 80 feet below the ground surface as shown on Table I,
Results of Resistivity Investigation.
The glacial debris material which ranged in thickness in the Test Holes
from 5 to 45t feet, consisted of cobbles and boulders wjth a highly variable
gravel , sand, silt and clay nratrix. The glacj a1 material was medium dense to
dense, moist, gray to brown to reddish brown. There was generaliy a 1to 2
foot interval of sandy clay topsoi'l nraterial not indicated on the txpioratory
Boring iogs due to the excavation of the drilling access road. we estimate
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that 50% to 75%oO. upper glu.totorua.rial is.lr" and boulder size.
As jndicated by the tesb borings and boulders vrhich are on the surface, the
maximum boulder size is approxitnately 6 feet. The Gradation Test Results
as sholn on Fig. 3 to 6 general ly indicate material which is less than
1U? inches in d.i ameter. The maximum size obtajned with the 2.0 inch 0.D.
split-spoon sampler is 1I/2 inches. There were areas in the borings where no
cobble or boulders were encountered for approximately 1foot. I,le do not believe
that these zones are very large in ejther lateral or vertical extent.
The bedrock encountered jn the test borings at the site was generally a
massjve gray limestone wjth thin interbeds of shale, siltstone and sandstone
which varied in color from gray to pink. Several attempts were made to get
samples of the bedrock but standard sampling procedure usinct the 140 pound
hammer wou.ld not penetrate the bedrock. Cuttjng samples were obtained vlhere
rotary drilfing rvith a drag bit or roller bit w,ls used. A core sample was
obtained using a diamond tipped core barrel for an 8 foot jnterval in TH-5.
There vras 100% core recovery in the 2 core runs and a 100% "RQD" (rock quality
designation) in the lorver 5 foot core jnterval . There is a general 30 degree
bedding plan indicated in the core from TH-5 which we believe corresponds to
the general dip vrhich uras observed in sedimentary outcrops in the area of the
si te.
No free water was encountered in any of the test borings at the time of
drjlling, nor was groundwater observed in the borings up to 3 days after the
bori nqs were dri I I ed.
SLOPE STABiLITY
The proposed construction site is a fairly uniformly sloping site with
an average slope of approximately 2,5 to 1 (horizontal to vertical). Sub-
surface condjtions at the site were relatjvely erratic. Generally the depth
to bedrock was more shallolv on the west and north sjdes of the property with
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the thickness of overburden soirs increasing sharply to the east. Depth
to bedrock ranged from as rittre as 5 feet to the weathered surface to
approximately 80 feet. 0n the west side of the site, proposed building and
retaining wail cuts wiil probabry expose the underrying bedrock. Our borings
indicate that approximately 30 feet of glaciar materiars urir cover the
bedrock near the southeast corner of the u,estern most buirdinq. The eastern
buiiding and excavations for retaining wails will expose the glacial sand, gravel
cobble and bourders. Resistivity testing indicates depth to bedrock in the
eastern portions of the site to be on the order of B0 feet. currently pro_
posed plans indicate a major retaining wall on the uphill side of the struc_
ture. The required depth of cut to be retained ranged from approximately 12
feet at the west end of the site, to 17 feet near the middre of the site
and nearly 24 feet at the east sideof the site. There is a step in the
buildings located approximately 'i n the center of each building. current plans
show a grade change of 9 to r0 feet at this point with a reta.i ning wail re_
quired in the center of the structure.
In our stabirity analysis we considered the current configuration of
the site and the proposed site grading after construction. The existing
slopes are in a stabre configuration. Bedding plane siides are not Jikely
because of the reverse dip and srides against the bedding planes are unrike.ly
because of the massiveness of the rimestone. tJe considered two types of slide
action possible. A massjve deep seated slfde betlveen the surfjcial materjals
at the contact of the surficial materials with the bedrock and s.l .iding in
the upper surficiar materials. The dense gravel and bourder soir possess
relatively high inplace shear strength va'l ues. It is impossible to make
representative laboratory tests because of the size and gravel content of
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the soils on the site. In our opinion, the effectjve shear strengths of
soilare controrled by the finer portions of the sand and graver matrix.
our anarysis rve used friction angles ranging from 30 to 40 .egrees. r,Je
encountered no In/ater in any of the borings on this site and there was no
lvater severa'l days after driJling. surface examination at the site indicates
that it is a dry slope. Theoreticar stabirity analysis of the graveriy soils
on a 2.5 slope indicate the sl0pe is stabre with a relativeiy high factor
of safety. Our anaiysis indicate factors of safety ranging from 1.9 to 2.3
for the existing srope configuration. These are based on an assumed friction
angle of 35 to 39 degrees and an inplace average unit weight of approximately
135 pcf. The proposed cuts indicates theoreticar factor of safety after con_
struction ranging from 1.6 to 1.g depending on the assumed strength parameters.
In all of our strength analysis, we have negrected any cohesion component of
strength.
Our anaiysis indicates that the site wiil be stabre after construction.
The analysis of this type of site is interrelated with the proposed cuts and
building configurations. If the building is redesigned because of other
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considerations, it vrill be
to determine the effect of
necessary to make additional analysis of the sjte
changes in the design.
BUiLDING FOUNDATIONS
r're berieve bui)dings constructed on this site can be safeJy constructed
with spread footing type foundations. settJements of foundations wiil be
nominal. The soils exposed are relative.ly dense, granular materials. For
design of foundation elements for the structures, ure recommend sizing footings
for a maximum allowable soil pressure of 4000 psf. settlements under this
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I pressure vrjll be small. ile estimate maximum differential settlements on
_l the order of 3/4 of an inch. This pressure can be increased to 6000 psf for
I short duration total load conditions such as wjnd and seismic loads. In
add.i tjon, the 6000 psf allowable pressure can be used as an allowable toe
II pressure for desjgn of retaining wall footings'
| Our subsurface investigation encountered many large boulders- l'le an-
In ticipate very rough excavations at this sjte. Footing excavatjons can be
I Oifficult when the large cobble and boulders are encountered. To reduce
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concrete overrun it'i s possible to place compacted fine grave1 fill in large
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t potholes left in the foundation excavation as a result of removal of
i boulders. Either fil'l ing the potholes rv'i th lean concrete or placement of a
It .ontrol"l ed compacted fill will be satisfactory. Foundation excavation
: contractors must be vlarned of the possibility of very large boulders and
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difficult excavat'i on because of the presence of either iarge boulders or in
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I some isolated locations, massjve limestone bedrock'
Normal practice in the vail area is to provide a minjmum a 4 feet of
cover for frost protection for exteri or foundatjon elements. Interjor founda-
tion members can be p'l aced r,lith a minimum of 2 feet of confinement. The
confinement of ftlotings located at the downhill edge of structures on hjll-
sides sometimes is a problem. tle recommend designing the footings for the
allolvable pressure presented in this report and submission of the proposed
bu'i lding cross section for review. If the pressure from the foundations can
be contained r,,ithin the slope, no reduction in a.l lowable pressures will be
neces sa ry.
Continuous foundation vralls should be reinforced top and bottom to span
local anomalies in the subsoils. t'le recommend that foundation t^ralls be de-
signed to simply span a djstance of at'l east 10 feet'
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RETAINING bJALL DESIGN
type retaining walls should not be used at this site. If
large cuts of the nagnititude planned are to be carried out and maintained
Tho r r nnor
wall indicated by the plans, ranges from 12 to 24 feet jn heiqht. A 12 foot
high retain'ing wail at grade wiil require a total height of wall rangfng
to nearly 17 feet because of the amount required for cover of the dor,lnhill
footings. The cost of thfs type of construction is very high. If at all
po:;sible, we recommend maintaining maximum cut slopes of 12 to 15 feet which
wili result in retaining walls less than 20 feet high. Retaining wa11 heights
greater than 20 feet are possible but the amount of rejnforcement required
becomes excessive. The walls located on the uphill side of the site must be
designed to retain sloping backfitt. This will result in higher earth loadings
than a normal flat backfill. l^Je suggest use of the Culmann graphica'l procedure
to determine the actual pressures on the wall after the configuration of the
wall and the backfill has been determined. Actual pressures cannot be deter-
mined at this time because of the lack of sufficient detail. The eastern half
of the site at the present design grades will result in some very high re-
taining walls. It may be more efficient to use counterfort type walls on the
eastern portions of the property. For design purposes ire recommend using an
allowable friction angle in the backfjll soils of 35 degrees, an angle of
vrall friction equai to 17 degrees and a unit vreight of the backfill materials
of 125 pcf. The coeFficient of sliding between the footinss and the so.i ls
should be no greater than 0.45.
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There are
archi tectural
other flexi bl e
tr'ro major retaining wa11s planned at this site. The currenu
drawing indicates railroad tie type lvalls. Ra'i lroad ties anq
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retaining walls to provide lons term stabilit
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q- The backfill soils lvill probabiy have
contain excessive amounts of Iarge cobble
impossi bl e to use for control I ed backfi I I .
be imported. 0nsite soils
boulders and wi1l be virtually
to
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stone jn backfill behind the retaining walls should be 6 inches. The backfill
for the walls should be a reasonably we1 1 graded gravel ly material ranging
from a maximum size of 6 inches down. clayey backfill should be specifically
prohibited by the specifications. Immediately beh'ind the uphill face of aIl
retaining walls on this site, we recommend inclusion of a drainage blanket.
The drainage fill should be washed gravelly sand with approximately 40%
passing the No. 4 sieve and a rnaximum of 5% passing the No. 200 sieve. The
gravel drainage b'l anket should be a minimum of 18 inches of thickness, should
be piaced on the uph'i 11 side of the wall and should extend to within approxi-
mately 2 feex of l;he finished grade behind the wall. The upper two feet of
backfill behind the retaining wall should be more impervious soils available
onsite compacted to high density. There should be an ppen joint or perforated
drain tjie placed at the bottom of the wall to collect any moisture that
might be collected by the drainage fi11. The wall backfill should be mjnus 6
inch rnaterjals compacted in loose lifts of approximately B to 10 inches to
a mjnimum of 95% standard Proctor density (ASTM D69B-70). It js essential that
the materials placed as backfill on the uphi1l sides of the major retaining
tvalls be carefully compacted. -Placement and compaction of these fills should
be under continuous inspection by a competent soils engineer.
The current building configuration shows 6 retainingwall in the mjddle
of each buiiding running in an east-vlest direction urith a grade change of
approximately 9 to 10 feet. This type of construction is possible. There are
scvcral undesirable effects from a structural point of view. The ylall can be
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constructed as a free standing retaining wall or the building frame designed
with a concrete floor at the first level and loads from th.i s urall trans_
ferred into the frame of the structure. This type of construction is not
desirable, but necessary on hillside locations. placement of the wal'l and
compaction of the fill under the best of circumstances will result in some
rotation of the wal l during constructjon and poss.i b1y after constructfon.
The rotations are necessary to develop the shear strength of the soil. To
mjnjmize the effect on the overall construction of the structure, we believe
some selective construction techniques will be necessary. The best procedure
would be to construct the walls as free standing retaining wails and back-
fill the wa11s prior to any construction above the vralls. If this procedure
is selected most of the rotatjon r"rill occur during the backfilling process.
The wall should be detailed vrith sufficient alicrrvance for movement to mini-
mize the effect of the slight rotation on construction. If precast type ele-
ments are used t're suggest that the details be carefuliy revievred. Otherwise
it may be very difficult to get a proper fit. Backfill behind the lower
rctaining ivalls should be identical with those r:n the upper retaining wal'l .
It will be necessary to use a select backfjll rnaterial . The lower wall will
be a conventional flat backfill and can be designed as a free standinq wall
for an allowable equivalent fl uid pressure of 35 pcf providing select backfill
as described above is used. A drainage layer must be provided on the uphill
side of the vrall. If the vrall is totaliy restrained for example, with a
concrete floor at the first levei, it will be necessary to design the wall
for an equivalent fluid pressure of 5b pcf plus any appropriate surchage.
l'le have had the experience of observing this type of construction in
thc Vail area and Lhe influence of these major retaining vralls on construction
of sjrni lar condorninium structures. Our experience has been rather neqatjve.
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,t'lalls of this nature are difficult to construct and contractors generally
are reluctant to follow backfiliing procedures necessary to get good long
term performance. It is our opinion, that,g:j,ll- of these wars shourd be
constructed and backfilled prior to initiating any other form of construction
on this site, This will cause difficulty in construction scheduling. l,,le
observed construction of a similar wall in the summer of 1923 in the Dillon
area. Construction of the vtall took an experienced major commercial contractor
from the Denver area nearly 8 weeks to accompiish for a wall approximately
400 feet long and ranging in height from 15 to 25 feet. 0n this site, there
are two walls of siniilar height. construction should not begin until spring
runoff is complete to avoid excessive moisture in the near surface 'layer
and local slumping. This will seriously limit the construction season. A
possible alternative and one which certainly bears consideration is to con-
struct the walls during the late summer or early fall of the initial season
and begin construction on the site the fo1 lowing season. Recent delays in
reinforcement deliveries and other problems of slope construction indicate
that these may provide major construction delays and difficurties.
Ternporary construction slopes behind the retaining walls of 1.5 to l will
be safe. These slopes must be checked during construction by a soiis engineer
to determine if local flattening will be necessary- steeper slopes of 1to 1
m,ty be possible however, conditions must be observed during construction to
bc sure of l to l siopes rvill be temporarily stable. The presence of the large
stones and boulders wi11 probabiy create more probiems in the excavation
of thcse l'air1y steep slopes. Because of limited working room on the site, we
bel.i eve it will be almost essential to start on the uphiil wall and work
down slope during the excavation process. It appears on the preliminary 1ay-
outs thcre nray be enough working room to construct both walls simultaneouslv.
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FLOOR SLABS
' The natural onsite soirs will provide adequate support for srab on
grade construction. If nel fills are required to support slabs on grade we
recommend that they be onsite or similar graveliy soi'l s compacted to at least
95% standard Proctor density (ASTM 0698-70). Materials smaller than 3 inches
should be used to place as fiil to support froor s'l abs. In addition, inside
the building area where plumbingand other subfloor type utilities will be
placed, large materials should be excluded from the backfill. we recommend
frequent control ioints in all slab on grade construction to minimize slab
curling problems. Provision of a 3 inch layer level.ing course of sand is a
good design detail at this site. The sand layer will greatly enhance the
contractor's abi'l ity to provide a uniform surface prior to pouring slabs on
gr"ade.
SURFACE DRAINAGE
The site lies on the s'lope from the high country above the building area
r'rhich drains directiy into the Gore creek vailey. During the spring runoff
periods, extensive amount of runoff flow rapidly downslope and across the site.
control of drainage r,rill be essential. If the backfills around these walls
uphill from the structures become saturated during the spring runoff per.iod,
it is possible to initiate siumping or excessive pressure on the retaining
uall structure and resulting in rotation, distortion and other problems with
foundation walls. The design must include provision for interception and
control of surface drainage and routing of the drainage. l,le recommend rout.ino
of thc nater around and arvay from the foundatjon walls.
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to provide surface interceptor type drainage above the major retaining wali
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structure and route the drajnage around both sides of the structure.
Dr.rinage details around the building area should be carefu'l iy designed to
provide positive drainage alvay from the foundatjon walls. It is quite
easy to develop substantial anrounts of moisture and problems particulariy
jn below grade areas during the spring when ice buildup from the winter
rcsults in rapid runoff. These problensshould be carefully considered in
the design phases to provide for adequate drainage away from the structures.
All drainage must be designed to avoid saturation of the siopes and particuiarly
any saturation of new fi11s placed. The new fjll materials are very 1ike1y
to be more pervious than the natural onsjte sojls and slumping is a strong
possibility if these materjals beconre saturated.
LIMiTATIONS
Our borings were spaced closely to obtain a reasonably accurate founda-
tion picture, variatjons in the subsojl conditjons not indjcated by the borinqs
.lre all^lays possible. l'Je should inspect the completed excavatjon to confirm that
the soiis exposed are as indjcated by the borings. Placement and compaction of
fill as r.rell as installation of footings should also be inspected. At this
particular s'i te, performance of the slope is directly related to the proposed
cuts, fiils and inposed build'i ng loads. I,ie should be advised if substantial
revisions aremade in the proposed construction.
If we can be of further service in djscussjng the ccntents of this report
or in analysis of proposed structures from the soils and foundation viewpoint.
rr lca se cal l.
ROBERT t,l. THOMPSON, INC.
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By
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PR'PERTY "ou*o*"l|
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Joa No. 1698
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LOCATION OF EXPLORATORY BARINGS r-r9. I
83rO
8f,OO
82 90
8280
8260
8250
824 0
8230
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Et.8307'TH- 4
Er 8305'
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23/O
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20/t2 43/6
25/2
20/6
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JOB NO. | 698
LOGS OF EXPLORATORY BOR INGS
LEGEND:
TH-5
8t.8308'
83lO
8300
8290
82 80
4270
82 60
8250
8240
GRAVEL , SAI.IDY W ] TH CCJt3t JI-ES AND AO(JLDERS TO
6+ FEET IN :I[ZU, DEN';T, SCATTERED It FOOT
Tr-rIcK SAr,lt) t.AyfRS, :r{_ IGftTr,y I,iOIST. (Gp,Gp-G[4.GM)
WEATTIF-RED III.I)[II]CK, :;IIAI.E AND SILTSTONE,
MOIST, IIART). GRAY I0 I]I ACK
50/o
30/o
AEDROCK. I NTERT]EDDID I
VERY IIARD, I",I{ ) I 5T , GRAY
II,IESTt]i'E AND SIJAI-E,
I{) tiLACK
'o
PRACTICAI. T)RILL RIG RETU9- .WITIl 4 INCH
HEAVY DUTY Nt,GEf? . M(]I+E THAN CINE S,YMI]OL
INDICATES DEPT}I IN ADJACENT I()I E ATTEMPTED
AT.I;AME LOCA T IOIJ.
INDICATES LENGTII Ot: " NX'I (?.12'> INCIJ OIAIqETER)
SIZE CORE RUN. t\f,,Mllt-ll INDICATES PERCEiiT OF
SAMPLE RECOVETTF.D I'0fi L EI.JGTI.I CT']RFD.
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I DRIVE SAIiPLE, Trf SYMrylr_ 25,/5 INDTCATES
I TriAT 25 ttl_t)wS oF A I rr o pouND HAI\IMER FALL I r'JG
' 30 INCFES wEf?E f?FotrIRtD To DRIvE A z, o rNcH
SAf.1PI_ER 6 I NCllES.
I.{)TES:
( I ) RORINIGS WERE DRI{-I.IID .JIJNE IO-I2, I974 WITH A 4
INCH DOWN-IfTi.F{)LE. AIR PERCL,sSION HAMI4ER POWERED
I]Y CME55 DRILL RIG Ai.ID A 5OO CFM AIR COI4PRESSOR.
(2) TI"IE I]ORING WIIfT?E :]IT)WN h'AS CORED WITH AN II NXI'
SIZE D I AMIJI\ID TIPPED CORF TIARREL USING AIR TO REMOVE
CI.JTT I NGS FRON1 TI€ {TOR I tlc.
( 3 ) NO FREE WATER WAS FOUND I N THE I]OR I IIGS AT TIIE
TIME OF DRILLING.
(4) t-Lt:VATIONS WERE FURNISHID BY FRASIf:-R AND GINGERY
CONSII- T I IJG ENG J NEERS .
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STAIDARO
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LTQUTO LrMrT To PLAsrtctTY TNOEX %
s,.MpLE oF SAND, GRAVELLY, SILTY rRoM TH-l a 37 I
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GAAOATION TEST RESULTS
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J:.I] t{f,. I 698
GRAOATION TEST RESULTS
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Lf outo LrMrr % '.Llsrrcrry rNoEx 7o
SAMPLE oT GRAVEL, SANDY
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GRAOATION TEST
raov TH-3 O 12r
RgSULTS
HYO;IOIE ATiALYSI
oot orr oJ7 o?. r.t rr? J. rro lo "11:i---rE- r rc rCi E.r ---lii
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.c$ |{). 1698
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sAMPLE OF SAND, GRAVELLY, SJLTY FROM
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RESI. ;'IViTY TEST RESIL
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APPARENT RESISTiVITY
OHM-CM REMARKS
6a t4-dz>o
6Z 50-6 L y+
81 94-8 1 84
106 , OO0
200,000-
250, OO0
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DRILL HOLE TO
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210,000
l60,00o-
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BEDROCK AT ELEV.
8270.
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390,00o
90,000-
NO BEDROCK IN
DRILL HOI.E TO
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4 8305-8233
8233-8206
6 8308-8299
8299-A290
2890-4242
157 , 00o
230,0oo
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BEDROCK A299
MASSIVE LIMESTONE
8290-A276
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JOB NA. 1698 FIG.5
Trz&-
MEMORANDUM
T0: Pl ann j ng Conmi s s i on
FROlvl: Department of Community Development
DATE: December 9, 1976
RE: Sky Lion Proposed Special Development Di stri ct
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The aPPl'icant ProPoses 30 units
comparison of current zoning and proposed SDD
on 13.307 acres of land; a
ais as follows:
CURRENT
LOT
ZON I NG
AREA
ZONE
DISTR ICT ALLOWABLE UNITS ALLOI^JABLE GRFA
A-l
A-t
A-3
62,988
I .446 acres
50, 094
I ..|50 acres
4t ,l2l
.944 acres
Res i denti a'l
Cl uster
Res i denti al
Cl u ster
Agricul tural
l5II
28,270 sq. ft.
No Maximum
Assume 4000 Per unit
2l ,400
-4917O aTiorvable
65,3.l8 proposed
ExceptedParcel .l.394
Road &
Unplatted 8.373.|3.307 acres
Agri cu l tura'l
Agricul tural
PROPOSED SPECIAL DEVELOPMENT DISTRICT
-20 uniTF
30 units
' The proposal increases density fronr l'54 unjts per acre to 2'3
units per acre or an increase of approximately 49.8%. A GRFA increase of l8'648 sq' ft'
is requested whjch is an increase of approximately 40%, The request is cgmparable
to a request for rezoning A-3 and excepted from A to RC whjch would allow 29 unjts
total for the RC and 4 units on the A or a total of 33 units'
After a careful review by the Deptment of Conrmunity Development, the F'i re
Department, Department of Public works, and Royston' Hanamoto, Beck and Abey'
JI\I LIUII
Page Two
the staff has the following comments and concerns
proj ect :
relating to the proposed
I. DENSITY --The Department of Community Development report
concerning Lionsridge
indicated that potential population in the Lionsridge area shou'ld be m.i nimized.
Recent surveys completed as part of the Growth llanagement planning effort
further enforce the need to reduce population in this neighborhood, as well
as the entire Gore val1ey. The proposed density increase of approx'imately 50%
is not in line with the proposed growth management program and comprehensjve
plan. Proposed density per buildable accessible acres js 24 units per acre.
2. SL0PE -- 0f the total site of 13.307 acres, 9.557 acres
are in excess of 40% s'l opes with some portions in excess of l0%; none of the
site is less than 30% slope. Attached is a s'l ope analysis map.i ndicating the
area in excess of 40% slope and square footage calculations of areas less
than 40%
3. ENVIRONMENTAL IMPACT REP0RT -- The report as submitted 'is
unacceptable as it does not sufficiently address the impacts of the project
in the fo1 lowing areas:
a. Traffic -- The Environmental Impact Report assumes that
only 30% - 40% of the short-term visitors will bring a car and that the use
wil'l be minimized by Tovun of Vail bus system and the pedestrian overpass. These
assumptions were drawn from a report prepared by VaiI Associates for Lionshead
and we do not feel this area can be compared to Lionshead because of its
location. A traffic study prepared as a part of the potato patch .impact study
more accurately reflects this area and ind'i cates that each unit averages 6 auto
trips per unit per day. This could increase traffic on already coirgested
Sandstone Raod by as much as 1B0 cars per day.
tSKY LION
Page Three
.b.Fir.eplaces-.Impactof30firep.|aces.isnotaddressed.
A statement is made that since the project is so high on the side of the
va1.|eythatthewindwillblowthesmokeaway.Thisis-incorrectastheinversion
layer which creates the worse air pollutjon problems lies considerab'ly h'i glrer
thantheproposedproject.l{aturaldownslopeairdra.inagecouldcausefireplace
smoketoaggravateana.|readybadcondition.'Afireplacestudycurrent.ly
underwayind.icatestheGoreValleycontajnsmorefirep.|acesthattheair
shed and weather conditions will allow'
c. Populat'ion -- Population impact on the area was not
addressed,Givencharacterjstjcsforshort-termrentalunitsestablished
byTownofVailsurvey,5.gpeopleperdwellingunit,theprojectwouldhave
an impact of approximately 177 people at peak times' Given an estimated
population in Lionsridge of approximately 1300 people' this would be a
population increase of 13% - 14%'
d.BioticConditions--Astatementwasmadethatdisturbed
soils wjll be revegetated and additional Iandscaping will be added' Experience
has shown that revegetation on south-facing steep slopes has not been very
succes sful
e. Geg-lggj-g- -- The report submitted' again' was prepared
onlyforSiteA-3anddoesnotaddresstheproposedroadSystemandcul-de-sac.
0nthissteepsite,acomp.|etegeologicandso.ilsreportmustbesubmitted
which evaluates the project and sjte 'improvements as proposed'
f.Visual and Aesttre't'! r-!nrgg! -- refer to memorandum from
Bi l'l Pi erce.
4, DRAINAGE -- The preliminary drainage report as submitted is
not adequate for the ProPosed
large building lcoated on Lot
proiect as it was
A-3 and addresses
written sPecifical 1Y for one
only the Prevention of damage
SKY LION
Page Four
to the proposed building by a 100-year storm. It does not cover the'impact
of surface dra'inage on adioining sites, nor does jt propose a drainage plan
for the surface run-off. There appears to be a large natural dra'inage channel
on the west side of Lot A-2 which sesns to have a building located directly
in the center, A statement js made that drajnage w'i 1l be handled by a series
of swales and culverts as necessary. We feel that a complete drainage study
and p1 an is mandatory for a project of this magnitude wjth such a'large drainage
basi n.
5. R0ADS -- A statement is made that the max.imum grade of any
road.i s l0%. The cross sections and profiles, provjded at the most advantageous
'focations, indicate s'l opes of 13%+i our calculations, given the contours
provided on the site plan, jndicate that some of the corners are in excess
of Z0% slope which is totally unacceptable and unuseab'le in the winter. Due to
the extent of the road system and resjdentjal sites to be individually sold'
the Town of Vail would strongly recommend that a 40' dedicated road right-of-way
be required. The impact statement states the asphalt width wil'l be 25' and
the site p1 an scales on 20'of roadway width. The plivate roadway system
allows greater land area to be counted for GRFA&c'i rcumvention of maximun 12%
grades. 0n a road systen this extens'ive and steep, we. must have actual centerline
roadway profiles wjth stations and elevatjons, both existing and proposed;
and roadway sectjons to edges of cut and fjll every'l 00'' Without th'i s information'
it is impossible to evaluate both the environmental impact and useability
of the roads. G'iven the average snolvfall in the vail area and road slopes, it
would be impossible to p'low the snow up-hill. No snow storage areas have been
provided and plowing snow toward buildings on these slopes could creates "man-made
avalanche,,cond.i tions. It is further noted that the Zoning ordinance requires that
a'l I drives over 816 grade be heated.
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SKY LION
Page Five
6. UTILITIES -- A water system which incorporates a 90,000
gallon storage tank to assure water pressure is indicated on the plans; however,
there are no specific plans for pumps, pressure reduction valves or other
equipment. The Lions Ridge water District must be asked whether they are
willing to assume the maintenance necessary for this system; if not, jt
appears that owners could be faced with tremendous maintenance costs for the
extensive water system. A letter from Lyon-collins, represent.i ng the water
District' indjcates the ability to serve 25 units which were proposed on Site A-3.
They did express a number of reservations about wat'er pressure and precise
design of the system. Is the Lionsridge water D.istrict wjlling and able to
serve 30 units and accept the system as designed? The Div.i sion of water
Resources must also review the project in light of the requested, revjsed
service p'l an for the district. Impact of constructing the water tank was
not addressed and the tank site was not evaluated in the geologic report. An
access road of some sort would have to be constructed to the tank site both
for construction and maintenance of the facility. No such access is indjcated
on the plans or in the EIR.
" sewer connections to the main rine and between cu'l -de-sacs
appear too steep for construction and could further create a situation where
solids and liguids would separate and potentjally clog the lines. There are
also opposing flows at manhole jntersect.ions.
7, FIRE PROTECTION --The Fire Department has indicated that
the road grades are too steep for access and
turning radius less than the 30' required, for
the corners without backing up severa'l times.
of Lot A-l and both bujldings on Lot A-3 are
site steepness, If cars were parked in the
that two of the corners have a
ntaneuvering a fire truck around
The bujlding on the south side
inaccessible from one side due to
driveways, the uppermost floors of
Ja\I L I Ul\
Page Six
some buildings wourd not be reachable with the radder for rescue.
g. ECoNoMICS -- The EIR estimates the cost of site improvements
which seem to be unrealistic given the site characteristics. we have re-estimated
these costs based on our recent experiences in similar rocations:
ITEM BUDGET ESTIMATEq BY T0HN 0F VArL
El ectrical
Landscape
Roads
Retaining lla'lls
Sewer
!,later
l.later Storage
+ 25% factor
this visual site)
25,377 ' 55,000 (Based on cost in
Potato patch)
not incruded r6,000 ,il;{"r:;,:l:]r:|."il"."
seem to be necessary)
45,000
25,000
l7,900
25,000
50,000
45,000 (not re-estimated)
25,000 (not suff.icjent to screen
17,750
42,000
50,000 (not re-estimated)
--41-A!9* 4l,ooo
* report indicates totar of $207:21l'677
. $292'250
Cost per unit 7,656 9,742
Land Value Per Unjt ** 12,772 12,772
Construction Cost at $:S sq. ft. 63,000 63,000
C0ST PER UNIT $83,428 $85,514
** based on 4,398 acres in area B 0 $2.00 per sq. ft.
Based on both the deveroper's and Town of VaiIs estimates of
costs, the project does not seem to be economically viable. l.le must be cautious in
this respect as part of the site development could be completed and the project
not completed, leaving a visual blight -- we must not be faced with another
Page Seven
Sunburst of King Arthur's Court.
The Department of community'Development strong'ly recommends
the developer restudy the areas quest'ioned and that given the existing
proposal , the proiect be disapproved. The environmental impact report
subm'itted with the proposal is not acceptable. A third party, approved
by the Town of vail, must restudy those areas of the environmental impact
statement questioned.
Rovston
Hairamoto
Beck &
Abev
RE:
December 14, 1976
Mr. James F. Lamont
Department of Community
Devel opment
Town of Vail
P. 0. Box 100
Vail, Colorado 81657
Skylion Project
Project Review
Dear Jim:
0n December 9, 1976, I participated with you and your staff in a review
of the Skylion Submittal requesting designation as a Special DevelopmentDistrict. My conunents are as follows:
Plan Review
Because of the steep site slopes special and careful attention must be
given to road construction, wal I construction, slope stabil ity, site
drainage, erosion control , and site landscape. The solution to these
problems precedes any concern about building form or design.
The plans submitted were not adequate in representing proper solutions
to the above prob'l ems. Our adv'i ce to the Architect was to prepare
p1ans, in conjunction with a Civil Engineer, addressing the design
problems described above and to accurately estimate construction costsjnvolved. The project budget submitted appeared to be seriously deficient
and one must question project feasibility.
Project Report Review
The following are my conments per page. The pages were not numbered,
thus the numbers assiqned are mine.
Page 1 The Site
a. Slope characteristics in the developable area were not adequately
descri bed.
landscape Architects:
land Planning
Urban Design
krk Planning
Environmental Planning
Principals:
Roben Royston FASLA
Asa Hanamoto ASLA
Eldon Beck ASLA
Kaz uo Abey ASLA
[0uis G. Alley AIA
htricia Carlisle ASLA
Associates: 225 Miller Avenue
Harold N. Kobayashi ASLA Mill Valley
Robert T Batterton ASLA Califomia 94941
George w. Girvin ASLA 415 3E3-7900
Robert S Sena ASLA
Mr. James F. Lamont -2-December 14, L976
Page 2 - Utilities and Services
a. Gas may not be available to the site. A statement should be
made regarding economics and energy requirements of an allelectric project.
b. Fire access is difficult, not readily available.
c. Pedestrian access from the project to the referenced pedestrian
bridge is not shown on the plans. Sidewalks and/or steps could
be significant cost and space use factors.
Paq 3-4 - _Ue_ley.gbpmeq|
a. With the narrow roads described, guest parking can occur only
on driveway ramps. Is this adequate? Should streets be
widened or guest parking areas provided?
b.
d.
Reference was made to "possible heat pump/solar assist.', Afirm statement is necessaiy-wTEh proper evaluation as to costper unit and feasibility.
Reference is made to use of solar domestic hot water systems.
The system proposed must be described, heat storage defined,
and cost evaluation made.
Trash collector bins in screened areas adjacent to each building
gPPear to be physically difficult because of site grading.
These are not shown on plans and could be significant coit andv'isual quality items.
The report states that roads are 25 feet wide, plans show roadsat 20 feet. What is the road sectjon? 0n steep slopes everyfoot of w'idth is critical.
Roads in some areas are steeper than the 10% maximum listed.
The plan is not accurate.
Reference is made to a transient population. The organizationof a homewoners' association must be described. These home-
owners will eventualiy bear total responsibility for project
appearance and maintenance. Will they, in fact, be interested
and willing to bear the substantial long-range costs invo'l ved?
The developer must provide a management statement and relatedyearly project maintenance costs, nornally termed project CC
& R's.
First phase construction proposes building all roads and utiljties.
These are enormous front end costs. Does the developer bond and
guarantee iong-range road maintenance and snow removal for these
e.
s.
h.
, Mr. James F. Lamont -3-December L4, 1976
are aIl private streets. Wjll erosion control and project 'l and-
scape be complete at the outset? How long is the developer a
member of the homeowners' association bearing significant project
maintenance costs? Is the Town assured of fol 1ow {hrough in
terms of unit construction, or wilj the project erdin financial
straits after an enormous initial investment?
Page 5 - Quantitative Description of Project and Site
a. Incomplete
Page6-Nocomments
Pages 7, 8 & 9 - The Geology
a. The statement is made that there is "no anticipated use of high
retaining wal1s." This statement does not appear to be accurate.
b. Description of drainage techniques is incomplete.
c. Surface erosion characteristics of the soil when disturbed is
not described.
d. Compacted fill surface slope requirements are critical, yet not
stated.
e. The costs and techniques of the drain system is inadequate.
Page 10 - Drainage
a. An inadequate statement of a serious problem. Impacts both on
site and directly below the site bear serious liabi'l ities.
Pages 11 & 12 - Effects on Physical Conditions
a. The ability of residents to walk comfortab'ly to the pedestrian
bridge is not shown on the plans.
b. The opinion stated regarding smoke dispersal is not correct.
Page 13 - Hydrology
a. The statement is made that the natural surface has minor alter-ation. This is not accurate, the natural runoff and natura'l
conditions are dramatical 1y altered.
b. An analysis must be made of the impact of street gutter and drain
system runoff on the public streets and private properties be1 ow
the project.
Mr. James F. Lamont - 4 - December L4, 1976
Page 14 - Geologic and Biotic
a. The statement regarding slope stability is not adequate.
b. Regrading indicates probable significant surface
disturbance, rather than minor.
c. The budget described is not sufficient to mitigate
construction imoact.
Page 15 - Visual
a. The statement that the project design creates a more
natural merging of the project with the hillsjde than
does the existing lower project, is not supported by plans
s ubmi tted .
b. Reference to use of natural materials to solve construction
impacts is not supported by plans submitted.
c. The visual impact of this project as seen from the val1ey
and others will be highly significant. This is of concern
to the Town.
Page 16 - Table for Development
No comment.
Pages 17, 18 & 19 - 0utline Specifications
a. Site irrigation was not listed.
b. A Iandscape plan was not part of drawings submitted.
Page 20 - Budget
a. The budget did not include:
- Storm drainage- Imigation- Trash areas- t,Jal kways or steps
b. The budget does not appear to be adequate for landscape or
retaining walls.
Mr. James F. Lamont -5-December 14, 1,976
In conclusion, the best interests of either the Town or of future project
residents is not served by inadequate planning and inadequate cost projections.
Further project review should not be considered until complete and accurate
data is received. With such information in hand, a thorough project assess-
ment and preparation of an Environmental Impact Report shou'l d proceed.
HANAMOTO,& ABEYk
Ms Diana Toughill
Mr. Kent Rose
Mr. Bill Pierce
Mr. Terrell Minger
}.Ifl-
1'r
,
MINUTES - PLANNING & EWIRONMENTAL COMMISSIONPg. 5 6/L3/7e
Sandy Mi1ls wondered whether they could restrict by allowingno campers to park in the lot. Tom Jacobson was very adamant
about his feelings that the lot should not be a11owed, he
asked that this request be tabled.
Tom Harnid of Vail Associates, stated that V.A. will closethe lot for the surnmer, and that ln wj.nter there will be snow
berms to reduce the viSual impact, and also feels that they
would restrict overnight parking.
Pam Garton made the [Iotion to approve Vail Associates, Inc.request for Conditional Use Permit to allow a temporary publicparking lot in the LionsHead area, this Conditional Use Permit to
be effective for one year from this date, with conditions thatthe lot be open only during winter season operations and that it
be snow bermed as discussed and that the hours of operations belimited, the 1ot to be closed from 2 A.lvl . to 7 A.lU., and signedappropriately, and that no buses be allowed in the parking lot.
Gerry White seconded the Motion. The Commission voted 5 membersfor approval and Ron Todd opposed.
Gerry White is now chairing the meeting as Mr. Drager
was cal1ed away.
Number 7 on the agenda, Sky Lion - Request to rezone Lot 3,
Block A, Lionsridge Filing No. 1 from Agricultural to ResidentialCluster wlth a maximum of trvo dwelling units.
Dana Rickli addressed the Commission with this request.
IIe explained the site configuration and tbe fact there will beland dedicated to the Town of Vail through this rezoning.
Diana Toughill also gave the background for this request.After some discussj,on Scott Hopman made the Motion to approvethe request to rezone Lot 3, Block A, Lionsridge Filing No. 1,
from Agricultural to Residential Cluster with a maximum of two
dwelling units by Sky Lion, contingent upon the memorandum from
the Department of Community Development, and that approximately
8.6 acres are to be dedicated to the Torvn of Vail prior to issuanceof a Building Permit. Pam Garton seconded the l{otion, the
Commission voted approval by four members and Sandy Mills opposed.
Item number 8 has been postponed. The ll'lotion was made by
Sandy lUills that there be an indefinite postponement for the
VaiI lrlountain School, Lot 12, Block 2, YaiL VilJ-age l2th Filing
the request for a Conditional Use Permit to alIorv a private
school in an agricultural zone, this postponement requested bythe applicant.
Another Public Notice will be published and the Board of
Directors of the Vail Mountain School have been requested to hold
a meeting with interested citizens prior to their being put on
the Planning & Environmental Commission agenda, this to address
opposition from the neighborhood
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MEMORANDUM
.t
REF SIry LION PROPOSED REZONING OF LOT-3, BLOCKJ,,
LIONSRIDGE T'ILING NO. 1.
-
I5
4
ZE
I
TO PLANNING & ENVIRONMENTAL COMMISSION
FROI'I DEPARTMENT OF COI{IIUNITY DEVELOPMENT
DATE 8 June 1978
The applieant proposes to rezone to Residential
Cluster with a maximum of 2 dwellings on .944 acres of land
currently zoned Agricultural . A comparison of current zoning
and proposed rezoning is as follows:
CURRENT ZONING ZONE
I,oT AREA DISTNICT ALLOWABLE UNITS
A-1 62,988 Ilesidential
L.446 acres Cluster
A-2 50,094 Residential
1.15O actes Cluster
A-3 4l,L2r
944 acres Agricultural
Road &
Unplatted 8.373 acres Agricultural
PROPOSED REZONING A-3 2 uNitS
Net reduction in number
of units (3) units
The proposal decreases density from one unit per
1.86 aeres to one unit per 4.66 acres.
After a careful review by the Department of Community
Development, the staff has the following comments relating
to the proposed project.
The Department of Community Development report con-
cerning Lionsridge at the time of annexation and zoning tndicated
that potential population in the Lionsridge area should be
minimized. Recent surveys completed as part of the Growth
Management planning effort further enforces the need to reduce
population in this neighborhood,as well as the entj-re Gore
Valley. The proposed density decrease is in line with the
proposed growth management program and comprehensive plan.
Pg. 2. Siy Llon Proposed Rezoning 8 June 1978
The geotoglc report was submitted for Site A-3
which indicates that the site is buildable. On this steep
site, a complete soils report and foundatlon design must
be submitted which evaluates the residence and site improvements
as proposed.
Design will be very important as the site is extremely
visible.
At the time Lot A-3 was annexed and zoned, the
council expressed their willingness to consider a workable
pLan and possible rezoning. The rezoning and dedication
would actually reduce the possible maximurn density by 3 units
and would therefore be in keeping with the growth management
plan.
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MEMOMNDUM
T0: (1) Planning Commission
(2) Djana Toughill
FR0M: William F. Pierce
Architect and Town of Vait Bui'lding Officjal
DATE: December B, 1976
RE: Aesthetjc Revjew of the proposed
SkY Lion Proiect
At Diana,s request I have reviewed at tength the visual impact of the
proposed Sky Lion development. My comments follow:
A.,Theconventionaldes.ignofthebuildingsisvisually
unacceptable on this steeply sloping site, The vertical character of the proposed
structures does not compliment the exjsting'land forms. A structure on this
site should step horizontally into the slope of the hil'l at each vertjcal
floor level to minimize its visual impact.
B.Theexistingdrainagewayonthewestsideofthesite
is disturbed by placement of structures and access roads. More respect must
be paid to the existing land forms for v'i sua'l harmony wjth the existjng and
future environment.
c.Duetotheslopingcharacterofthesite,thevisua.l
impact of any vertical build'ing surface js increased' 0pen space and landscaping
are screened by bujlclings when vjewed from below. Adequate visual screening with
heavy plant material would be inordinately high in cost in that trees of significant
height would be necessary to be effective in a visual sense.
' Page Two
D.Thjsleadstoaquestionswhichisquitegenera.|.in
nature. In a Colorado mountain valley, which side of the va1ley'i s more
acceptab'l e for buildjng? North-facing slopes are general]y graced with natural
dense tree cover, thereby providing excel'l ent screening for developments'
south-facing.s1opes, on the other hand, are generally devoid of s'i gnificant
native tree cover making any artificial disturbance to the environment visually
prominent. vjsually, developments should be confined to the valley f'l oor or to
the north-facing sloPes.
E.Vjsually,cutandfi.|.lslopes.areagreatproblemjnthe
Vail Va11ey. Efforts to provide vjsually attractive retajnage' especially on
the south-facing slopes, has proved futile. Measures' such as those used on
the Vail Pass construction, to modify land forms to acconmodate roadways are
very expensive and environmentally questionable. Earthwork of that scale seeills
impractical on this site.
F.Duetothehjghcostsofaccessways'grading,uti.lity
placement and adaquate landscaping, it seems that some comprom'ises in design may
be necessary to make the project competitive financially, Due to the visual
prom.inance of this site in the Vail townscape, any compromises aesthetically
would be inaPPropriate.
In conclusion, I fjnd the project quite unacceptable' Deta'i 'l s of the
arch.itectural treatment of the structureswerenot investigated at this time;
in that, I f.i nd the conceptual forms'i nappropriate. The entire project must be
completely rethought with high priority giyen to creatjon of structures and their
inrpact on the environment.
box 10O
rail, colorado. 81657
(3031 476-5613
I
department of community development
June 16, L978
Mr. Dana Rickli
120 W. Alameda
Denver, Colorado
Dear Mr. Rickli:
' /our request to rezone Lot 3, Block A, Lionsridge FilingNo. l, known as Sky Lion, from Agricultural to ResidentialCluster with a maximum of two dwelling units was broughtbefore the Planning & Environmental commissi-on on Juhe 13, lgzg.
This letter constltutes notification that this requesthas been approved and granted by the P.lanning & Environmental
Commissj-on by a vote of 4 to 1, and is granted contingent uponapproximately 8.6 acres of land to be deeded to the Town of Vailprior to issuance of a Building Permj.t. This decision willbe heard by the Vail ?own Council-on July 18, l9Z8 at 7:30 p.M.
Sin
S. Toughill
Administrator
DST/gew
lana
Zoning
-l
PUBLIC NOTICE
NoTIcE rS HEREBY GrVEN THAT Dana Rickli, representing
the owners, has applied for a rezoning of Lot 3, Rlr'nk Ar-
Llonsridge Filing No. 1 from Agrlcultural to Besidential
Cluster Zone District with a maximum of two (2) dwelling units.
Application for rezoning has bedn made in accord with Section
18.66.O60 of the Municipal Code for the Town of Vail.
A Public Hearing will be held pursuant to the
provisions of Section 18.66.060 of the Municipal Code on
Jul5r 18, 1978 before the Town Council. Sai.d hearing wtll be
held in the Vail Municipal Building at 7:3O P.M.
TOWN OF VAIL
DEPARTMENT OF COI.{MUNITY DEVEIOPMENT
i r ^ '':.-::' "'
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Diana S. Toughill
Zoning Administrator
Published ln the VaiL Trail June 23, 1978.
/
PUBLIC NOTICE
NOTICE IS HEREBY GIVEN THAT Sky Lion partners of
rezoning and resubdivision of Lots l, 2, and 3, Block A,
Vail have requested
excepted parcel and parcel
described by metes and bounds, Lionsridge Filing No. l, from residential cluster
and agricultural to Special Development District to allow development of the site
in a more unified manner, App'l ication has been filed pursuant to Section 2I .500
of the Zoning 0rdinance, Ordinance No. g, Series of .|973.
A Public Hearing will be held on December g, 1976 before the Town of Vail
Planning Comrnission in accord with Section 21.400 of the Zoning 0rdinance. Said
hearing will be held at 3:00 pM in the vail Municipar Building.
TOWN OF VAIL
DEPAPTY'*' OF COI{'IUNITY DEVELOPMEIIT
..),,.. /.-/ /,/
K^K4;{;,#rr/'{/
Zoning Administrator
Publ ished in the Vail Trai'l November '19, .l976
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Town Council
Town of VailVaiI, Colorado
Re: Ordinance NumberDistrict Number
Sky Lion at Vail
Ladies and Gentlemen:
OECLAN J. O'OONNELL
ROBERT L. HARRIS
OF COUNSEL
DAVID A, SCHOYER
aSsocrAtE
October 25t L976
3 I 2 UNIVERSITY BOULEVARO
OENVER, COLORAOO AO2O6
(3O3) 3 99-8171
This will represent the application of sky Lion partners at vair forestabl-ishment of a special Development Di;trict by ordinance, a copyof which is attached hereto, This appLication includes a request ?orzoning change.
Architect Dana Rickli has prepared a scale model of the sky Lion de-velopment that shows in some detail the intended utilization of theapproximate 13 acres. Multiple dweLling units are clustered on theLower ground and single-family sites are located above. The road sys-tem is extended across the area at gradual slopes to avoid any steepgrades and minimize the need for cuts and fill;. All utilitils willbe_underground and adeguate provision made for drainage. The proposedord.inance also requires the usual set backs and distances between-structures, as wel-L as height and square footage standards for con-struction.
The neighboring structures immediately berow this proposed projectconsist of the Lions Mane and Home stlke buildings. irrey c6*piise theNorth border of development in ttre Lions Ridge aiea. th-e comiarative-1y massive size of these structures tend to irake the North boider ofLions Ridge appear to spring-up too abruptly. The sky Lion plan wouldround off the North border with more conservative devllop..ni. An im-portant zoning advantage of the sky Lion plan, in an estlretic sense,would be amelioration of this abruptness in favor of a more gentleappearing circumf erence.
Also, the existing fill on the old ]-oop road has an incongruous yellow-green strip effect on the olive-colored hill and this would be airelio-rated. The existing d,g-zag construction road cut into lot A-3 wouldbe corrected too. The entire 13 acres would blend, betler as a buffer
October 25, L976
Town Council, Town of Vail
Page 2
between the National Forest and the massive buildings of down-'town
Lions Ridge.
I night mention that the Sky Lion Project should contribute favorably
to the personalLty of Vail. This land is gorgeous. It would be a
shame to deny guests and residents of vail the spectacuJ-ar view and
exclting experience of sky Lion. Tne neighboring Potatoe Patch area
has set a high standard of great expectations.
The change in zoning implicit in the proposed development district
application is a change in Lot A-3 and the West half of the old loop
road from agricultural to R.C. zoning. The result is that 6.844 +
acres wi1l be agricultural and that 4.934 + acres will be R.C. zon-ing.
This extends the existing R.C. zoning on Lo-ts A-l- and A-2. The net
up-zoning effect is to change 1.802 acres from agricultural to R.c.
This is quite compatibte with existing uses. There is no request for
any commercial zoning. The entire area would be dedicated to light
residential use.
Lot A-3 has been zoned for high-density condominium development by the
County of Eagle for roughLy 10 years. Contemporaneous with annexation,
the Town of Vail down-zoned it to agricultural . Neighboring Lots A-1
and A-2 were zoned R.C. The present application. covering approxi-
mately 13.307 acres, is considered to represent a compatible and uni-
form treatrnent of lots within the District, as well as an aPpropriate
plan for the North border of Lions Ridge. This should promote the
objectives of the zoning ordinance without discriminating or granting
special privLlege of any kind.
The effect of the requested variance on light and air for neighboring
projects would not be adverse because Sky Lion would be up hill to the
North and across the road from them. The current useage of the road
to the project is limited to Lions Mane and Sky Lion, for all practical
purposes. It certainly has capacity to serve the subject project. The
interior road system will be privately naintained so that no additional
burden is foreseen for the Town of Vail. A bus station will be located
on the South East corner of the property to accommodate access to
existing bus service. There wilL be a slight increase in density re-
sulting from the up-zoning of l-.802 acres from agricultural to R.c.
However, the distribution of population within the Special Development
District is geared to compliment the terrain to the full-est degree,
with residential units grouped appropriately along the well-planned
road system, rather than being placed more arbitrarily on existing
October 25, L976
Town Council, Town of Vail
Page 3
parcels. In this manner, the use of the Special Devel-opment District
provides a more J-ogical distribution of population within the District
and more than Justlfles the slight increase in density.
Any additional data, corunents or analysis will be supplied upon reguest.
Sincerely,
A*h/"\*!
DECIJAN J. OIDONNELL
DJO: fg
Enclosure
\
November 5, 1975
Dana Rickli
2862 S. Otis
Denver, Colo 80227
RE: Sky Lion Condominiums at Vail
E lectric Serv i ce
Dear Mr. Rickli
The following is a sfatement of facts as re la+e to availability of electric
service to the Sky Lion Condominiums at Vail project locafed in Lot A 3 of
Lionsridqe Subdivision Filinq #1.
Item l.
Item 2.
Item 3.
lfem 4.
Item 5.
lfem 6.
Holy Cross Electric Association, Inc., is the certi f icated
electric public utility in the area in question.
An overhead, three phase high voltage power line exisfs on orjust North of Lot A 3. This power line is a part of the main
distribution system fhat Holy Cross Electric uses in serving
the Vail area. lt cannot be moved withouf substantia I expense
to the party requesting its movement.
Three phase underground power lines capable of serving a condominium
development on Lot A 3 exi sts on the Soufh side of Sandstone Drive.
It will be fhe ownerfs electrical subcontracforts responsibility to
extend two, four inch rigid steel conduits from a vault located on the
northernmost corner of Lot A 5 to an accessible transformer location
located on Lot A 3. lt will also be the electrical subcontractorrs
responsibi lity to purchase and install one transformer pad to meet
Holy Cross Electric Associationrs speclfication UMI-13, or UMI-ll
depending upon what size transformer is installed.
l2O/2O8 volt, three phase, four wire servlce will be available at the
transformer locat ion.
PLEASE ORDER 208 VOLT, ELECTRIC HEATERS, ELECTRIC RANGES, ELECTRIC
WATER HEATERS, AND ANY OTHER PHASE TO PHASE CONNECTED APPLIANCES.
,q
Mr. Dana Rlckll
2862 S. Otls
Denver, Colo 80227
Page 2
Item 7. lnstallatlon of the two conduits men+ioned ln above ltem 4 wlll
requlre the crosslng of Sandstone Drlve. The owner will be
requlred to make all inltial and permaneni road repairs requlred
by thls excavatlon.
Slncerely,
HOLY CROSS ELECTRIC ASSOCIATION, INC.
, M4./#
lf Rlchard D. Brinkley, System Engineer
I ..', steve I son
Eagle County
OO
4i"fror/o trgrruurt, Ltnc.
CIVIL ENGINTTRING . PIINNING . SURVTYS
SUBD|V|SIONS . WATT,R & SrWER 5y5Tt \5
Kenneth E. Richords
l4r. Michael S. Blair
Plar..ning Director
Post Of f ic€ tsox 789
Bagle, Colorado 81631
Re: File No. Sp-44-74
Sky Lion at Vail
Upper Eagle Valley Sanitatj-on District
Dear Mr. Blair:
Referring to my letter to you of March 25, 1974, which stated that the
Dist,rict could serve 39 condominiunr units and a 2100 square foot restaurant
on Lot A-3 Lions Ridge Subdivision, I understand now that there rvi1l be only
25 units and no restaurant. Sewer service will be avaifable upon payment of
the standard tap fees before tapping the District's rna in alld at the standard
service charges.
The pistrict has expanded its plant and additional improvements are
underway at this time- AIso, most line repairs have been completed anrl the
infiltration should be very much lower next year.
Sincerely,
RICHARDS ENGINEERS, INC-
Engineer
E. Richards
for the District
LFQ . ^r,
cc: .rames Collins, Manager
Al rlewelling, Superintendent
Upper Eagl-e Vall-ey Sanitation District
Michael Dawson
Morcus Realty and Tnvest(ent Co.
Dana Rickli, ARchitecE
Box 1908
Voil, Colorqdo 81657
Phonc 47 6-5072
Dcnver)Eipf :(Klgr 89 3- 1531
September 17, L975
Regislered Pro[essionol Engineers
Regirtered Lond Surveyors
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Ootda lt, 1975
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LOCAL GOVERNMENT MANAGEMENT CONSULTAI{TS
'" Denuer Office // 17,10 Wiltiams Street / Denuer, Colorado 80218 / Phone [303] ggg-7053
''' )a Offtce /i P.O. Box 82 / Vail, Colorado 81657 / Phone [303] 827-5274
lov. 23, lt?5
l|t. Xlehecl S. BlrlrDlrector, Dcprrtrcnt of Plranhg rnd
Ilcvelopncnt
Eeglc CountyP. O. Box 789
Er31o, Colorrde l16tt
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ldr. Mlchael
Novenbcr 25,
Pagc Tro
eS. Blair
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Jarcl P. Collinr
Lyon, Collins € Co., Iac,
DISTRIC-T T'IANAGEB
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6t:y*ountatn Propertl'es, Ltd.c/o Decleo O'Donrcll, Attf.
512 Unlversity Blvd.
Deaver, Colorado E0206
Ed llregerThorc ll. Lyster?ol Grisshar
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JOB NO. 1698
GRAOATION TEST RESULTS
FIG. 6
t.
TABLE OF CONTENTS
CONCLUS IONS
SCOPE
PROPOSED CONSTRUCTION
SITE CONDITIONS
GEOLOGIC SETTING
SUBSURFACE CONDITIONS
SLOPE STABILITY
BUILDiNG FOUNDATIONS
RETAINING I.IALL DESIGN
FLOOR SLABS
SURFACE DRAINAGE
LIMITATIONS
FIG. 1 - LOCATIONS OF EXPLOMTORY BORINGS
FIG. 2 - LOGS OF EXPLORATORY BORINGS
FIGS. 3 through 6 - GRADATION TEST RESULTS
TABLE I - RESISTIVITY TEST RESULTS
1
2
2
2
3
4
6
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CONCLUSIONS
1. Subsurface condjtions at the site consist of a highly
variable thickness of glacial grave'l s over hard limestone.
2. Groundwater was not encountered in any of the borings.
3. The average s'l ope of the natural ground surface is about
2.5 horizontal to L vertical . Theoretical stability analysis
indicates the present and the proposed site configuration
will be stable.
4. Extensive retaining wall structures will be necessary to
make the desired cuts and maintain site stabif ity. lle
recommend use of select backfill, drainage blankets be-
hind the walls, and construction of the required retain'ing
structures complete with backfill prior to building con-
structi on .
5. Large boulders and hard limestone bedrock were encountered.
Excavation costs will be higher than normal . Limiting cuts
will resu'l t in savings. For presently planned grades, a
boulder and rock excavation quantity should be included in
the bid documents.
6. Ljmited working room will be a prob'l en for both excavation
and general contractors.
7. Temporary construction slopes ranging from 1.5 to 1to 1to 1
(horizontal to vertical) will be safe. Long term cut slopes
should be 2:1. Long term fill slopes constructed with the natural
granular soils will be stab'le at 1.5 to l provided the height
of fill does not exceed 12 feet. Fills should be benched into
the existing natural s1oPe.
8. The proposed buildings should be constructed with snread footingt
type foundatjons.
-2-
SCOPE
This report presents the resurts of a geotechnical study for the Sky-
lion Project to be constructed in the Lion's Ridge Area, Vail, Colorado.
The report presents a description of the general site geology, subsurface
conditions, slope stabi'r ity analysis, recommended foundation systems, ailowable
soil pressures, groundwater conditions and design and construction criteria
infJuenced by the subsurface conditions. This report was prepared on the
basis of factual data gathered during the field and laboratory investigation
and our experience in the area.
PROPOSED CONSTRUCTION
we understand that two 3-story wood frame buildinqs are planned on Lot
A-3. Associated with the proposed buildings will be a swinrning pool between
the two buirdings, parking on Lot A-3 and the Exftprted tot to the east of
o
,O A-3, and retaining walls above and
ing areas will require cuts ranging
general'ly in a cut section with the
about L2 feet.
through the proposed buildings. The park_
from 12 to 20t feet. The buildfngs are
maximum cut in the building area of
SITE CONDITIONS
Lot A-3 and the Excepted rot to the northeast of Lot A-3 are generaily
located northwest of Red sandstone creek and north of Interstate 70 within
the Lion's Ridge area, Vair, cororado. The site is rocated directry northwest
of sandstone Drive which reads into the Red Sandstone creek Road.
The site ries on a moderate to steepry sroping south facing srope. The
natural slope averages about 2.5 to 1 (horizontal to vertical). The site was
undeveloped with a fairly even slope across the site. There was a small area
_ 3_
at the southern limits of the property which had been excavated for gravel .
The southern and southeastern limits of the property border Sandstone Drive
which has been constructed as a cut and fill section. Along the southeastern
limits of the Excepted lot east of Lot A-3 there is a cut slope approximately
20 feet high which is standing on a 1.5 to 1(horizontal to vertical) slope.
Generally to the northeast and the southwest, the hillside is regular and
continuous as it is within the investigated lot. Above the investigated
Lot A-3 and Excepted lot there is an area shown on Fig. l, Location of Ex-
ploratory Borings, as the Lion's Ridge Loop which is an undeveloped road
easement. This area was stripped of vegetation in the past but had been
overgrown by grass and small shrubs.
At the time of our investigation, there was no development on site.
During our investigation rough construction roads were developed on the site
to provide access for drilling equipment. Development within the area but
not within the limits of the investigated site includes underground water,
sewer' electrical and telephone lines within the easements of Sandstone Drive
and overhead transmission'l ines a'long the Lion,s Ridge Loop easement to the
north-northwest of the investigated site.
GEOLOGIC SETTING
The investigated site lies within the g'lacially formed vail valley.
This site is on the'limits of the valley wa'lls which are generally moderate
to steep in slope. The entire site is below the upper limits of g'laciat
act'ivity along the north-northwest side of the valley, The entire surface
within the site indicates glacia'l materials. There are outcrops of sedimen-
tary formations located higher on the slope above the investigated site and
to the west and southwest at e'levations continuous with elevations in the
a -4-
investigated site. Generally the formations which occur higher above the
investigated site are the bright red congo'l omerate, sandstone and sirtstone
of the Pennsylvanian and permian Maroon Formation. To the west_southwest
at elevations equivalent to those found within the investigated site are
interbedded limestones and shales of the pennsylvania and permian Minturn
Formation- samples of the bedrock encountered during the drilring phase of
our investigation were of red, pink, and gray limestones, sandstones, and
shales indicating that underjying the surface glacfal overburden is bedrock
of the Maroon and Minturn Formations. Outcrops within the general area had
attitudes ranging in strike from N60E to N82E and dips to the northwest ranging
from 20 to 32 degrees. The dip of the sedimentary formations is opposite to
the slope of the valley. The natural vailey walls are a reverse slope to the
sedimentary formations. Bedding prane slippage does not appear possibre.
There are no topographical or vegetational indications that there is
any subsurface water along the slope on which this site is-located. l^le
believe that the majority of rainwater and snow melt is carried as surface
water due to the steepness in slope.
SUBSURFACE CONDITIONS
subsurface conditions were investigated by drilling 6 borings at the
locations indicated on Fig. 1, Locations of Exploratory Borings. The
borings were attempted with a 4 inch continuous flight power auger at the
location of Test Hole No. 1, but it was not possible because of the large
cobbles and boulders. The exploratory borings were drilled with a 4 inch
diameter down-the-hole air percussion hammer powered by a cME 55 drill rig
and a 500 cFl4 air compressor. When the upper overburden material of boulders
and gravel was penetrated, the bedrock was rotary drilled with either a
a
o 3
"drag 6i1" or "rolrer bit" or NX sized diamond tipped core barrer usingair to remove cuttings from the borings.
' Generally two types of subsurface materials were encountered in theborings as shown on the Logs of Exploratory Borings, Fig. Z. The twogeneralized subsurface units were (i) glacial debris which consisted ofboulders and cobble gravelly sandy matrix; these soils were medium denseto dense, moist and gray to reddish brown, (2) weathered bedrock and bedrockwhich incruded interbedded shaIe, sandstone and limestone. The bedrock wasprimarily a very hard gray limestone interbedded with thinner beds of shale,siltstone and sandstone which were arso very hard. goth the overlying glacialmateriar and bedrock layers vary considerably in thickness. The depth tobedrock was very erratic and ranged from g to g0r feet. As indicated by theLogs of Exploratory Hores, Fig- 2, the bedrock surface is near tt,. grornasurface at rH-6 (erevation g2gg) and sl0pes moderatery to the east to therocation of rH-2 and TH-5 where the bedrock surface begins to srope steepTytc' the east. Bedrock was not encountered in Test Holes 1 and 4 to depthsof 45 feet. ,ue investigated the depth to the bedrock surface at rH_l andTH-4 using erectricar resistivity equipment which indicated that bedrockwas approximately 70 to g0 feet berow the ground surface as shown on Table I,Results of Resistivity Investigation.
The glac'ial debris materiar which ranged in thickness in the Test Horesfrom 5 to 45t feet, consisted of cobbres and bourders with a highly variablegravelr sdrdl silt and clay matrix. The glacial material was medium dense todense, moist, gray to brown to reddish I)rown. There was generally a I to 2foot intervar of sandy clay topsoir material not indicated on the ExploratoryBoring 10gs due to the excavation of the drilling access road. ,ue estimate
o
that 50% to zs,O the upper gtaciat6rlr""iut ;lnnru and bourder size.
As indicated by the test borings and boulders which are on the surface, the
max'imum boulder size is approximately 6 feet. The Gradation Test Results
as shown on Fig. 3 to 6 genera'l ]y indicate material which is less than
r r/2 lnches in diameter. The maximum size obtained with the 2.0 inch 0.D.
split-spoon sampler is 7 7/2 inches. There were areas in the borings where no
cobble or boulders were encountered for approximately 1foot. 14e do not believe
that these zones are very large in either lateral or vertical extent.
The bedrock encountered in the test borings at the site was general.ly a
massive gray Iimestone with thin interbeds of shale, siltstone and sandstone
which varied in color from gray to pink. several attempts were made to get
sanples of the bedrock but standard sampling procedure usin5l the 140 pound
hammer would not penetrate the bedrock. Cutting samples were obtained where
rotary drilling with a drag bit or roller bit was used. A core sample was
obtained using a diamond tipped core bamel for an g foot interval in TH_5.
There was 100% core recovery in the 2 core runs and a r00%,,RQD,' (rock quality
designation) in the lower 5 foot core interval . There is a general 30 degree
bedding plan indicated in the core from TH-5 which we believe corresponds to
the general dip which was observed in sedimentary outcrops in the area of the
site.
No free water was encountered in any of the test borings at the time of
drilling' nor was groundwater observed in the borings up to 3 days after the
borings were drilled.
SLOPE STABILITY
The proposed construction site is a fairly uniformly sloping site with
an average slope of approximately z.s to 1 (horizontal to vertical). sub_
surface conditions at the site were relatively erratic. Generally the depth
to bedrock was more shallow on the west and north sides of the property with
-7-o
the thickness of overburden soirs fncreasing sharp.ry to the east. Depthto bedrock ranged from as rftre as 5 feet to the weathereo surface to
approximately g0 feet. 0n the west side of the site, proposed building and
retaining wan cuts will probably expose the underlying bedrock. Our borfngs
indicate that approximately 30 feet of glacia'l materials will cover the
bedrock near the southeast corner of the western most building. The eastern
building and excavations for retaining wails wiil expose the glacial sand, grave.r ,cobble and boulders. Resistivity testing indicates depth to bedrock in the
eastern portions of the site to be on the order of g0 feet. cu*en'y pro-
posed plans indicate a maior retaining wall on the uphill side of the struc_ture' The required depth of cut to be retained ranged from approximately 12
feet at the west end of the site, to 17 feet near the middle of the site
and nearly 24 feet at the eastsideof the site. There js a step in the
buildings located approximately in the center of each building. cuffent plans
show a grade change of 9 to r0 feet at thfs point with a retaining warl re_
quired in the center of the structure.
In our stability analysis we considered the current configuration of
the site and the proposed site grading after construction. The existing
slopes are in a stabre configuration. Bedding plane slides are not tikely
because of the reverse d'ip and srides against the bedding pranes are unrikely
because of the massiveness of the'r imestone. r,le considered two types of sride
action possible' A massive deep seated slide between the surficial materials
at the contact of the surficiar materials with the bedrock and sliding in
the upper surficiar materiars. The dense gravel and boulder soil possess
relatively high inprace shear strength varues. It is impossibre to make
representative raboratory tests because of the size and gravel content of
-8-
the soils on the site. In our opinion, the effective shear strengths of the
soil are control 1ed by the finer portions of the sand and gravel matrix. In
our analysis we used friction angles ranging from 30 to 40 degrees. l,|e
encountered no water in any of the borings on this site and there was no
water several days after drilling. Surface examination at the site indicates
that it'is a dry s1ope. Theoretical stability analysis of the gravelly soils
on a 2.5 siope indicate the slope is stable with a relatively high factor
of safety. Our analysis indicate factors of safety ranging from 1.9 to 2.3
for the existing slope configuration. These are based on an assumed frjction
angle of 35 to 38 degrees and an inplace average unit weight of approximately
135 pcf. The proposed cuts indicates theoretical factor of safety after con-
struction ranging from 1.6 to 1.8 depending on the assumed strength parameters.
In aIl of our strength analysis, we have neglected any cohesion component of
strength.
Our analysis indicates that the site will be stable after construction.
The analysis of this type of site is interrelated with the proposed cuts and
building configurations. If the build'ing is redesigned because of other
considerations, it will be necessary to make additional analysis of the s'i te
to determine the effect of changes in the design.
BUILDING FOUNDATIONS
l,le believe buildings constructed on this site can be safely constructed
with spread footing type foundations. Settlements of foundations will be
nominal . The soils exposed are relatively dense, granular materials. For
design of foundation elements for the structures, we recommend sizing footings
for a maximum allowable soil pressure of 4000 psf. settlements under this
O
-9-
Dressure will be sma'l l. We estimate maximum differential settlements on
the order of 3/4 of an inch. This pressure can be increased to 6000 psf for
short duration total load conditions such as wind and seismic loads. In
addition, the 6000 psf a1 'l owable pressure can be used as an allowable toe
pressure for design of retainjng wall footings.
0ur subsurface jnvestjgat'ion encountered many large bou'lders. |r|e an-
ticipate very rough excavatjons at this site. Footing excavations can be
difficult when the large cobble and boulders are encountered. To reduce
concrete overrun it is possible to place compacted fjne gravel fil'l'in large
potholes left in the foundation excavation as a result of removal of
boulders. Either filling the potholes with lean concrete or placement of a
control 1ed compacted fill will be sat'isfactory. Foundatjon excavation
contractors must be warned of the poss'ibility of very large boulders and
difficult excavation because of the presence of either large boulders or in
some isolated 'locations, massive ljmestone bedrock.
Normal practice in the Vail area is to provide a minimum a 4 feet of
cover for frost protectjon for exterior foundation elements. Interior founda-
tion members can be p1 aced with a minimum of 2 feet of confinement. The
confjnement of footings located at the downhjll edge of structures on hill-
sides sometimes is a problem. We reconrnend designing the footings for the
allowab'l e pressure presented in this report and submission of the proposed
building cross section for review. If the pressure from the foundations can
be contained within the slope, no reduction in allowable pressures will be
necessary.
Contjnuous foundation wal'l s should be reinforced top and bottom to span
local anomalies in the subsoils. lle recomrnend that foundation walls be de-
signed to simply span a distance of at least 10 feet'
-10 -
RETAINING I^,ALL DESIGN
There are two major retaining walrs planned at this site. The current
architectural drawing indicates railroad tie type walls. Railroad ties and
other flexible type retaining walls should not be used at this site. If
large cuts of the magnititude pranned are to be ca*ied out and maintained
successfulry' it wilr be essentiar to provide heavy reinforced concrete
retaining wa's to provide'rong term stabirity of the slope. The upperwa' indicated by the plans, ranges fron 12 to 24 feet in height. A 12 foot
h'igh retaining wall at grade will require a totar height of warl ranging
to nearry 17 feet because of the amount required for cover of the downhirlfootings' The cost of this type of construction is very high. If at arlpossible, we recommend rnaintaining maximum cut slopes of rz to 15 feet whichwirr resurt in retaining walls ress than 20 feet high. Retaining wail heights
greater than 20 feet are possible but the amount of reinforcement required
becones excessive. The wails rocated on the uphi.r l side of the site must be
designed to retain sloping backfill. This will result in higher earth loadings
than a normal flat backfill. l,le suggest use of tfre Ct'fffigraphical procedure
to determine the actuar pressures on the warl after the configuration of the
wall and the backfilr has been determined. Actuar pressures cannot be deter_
mined at this time because of the rack of sufficient detail. The eastern harfof the site at the present design grades will resurt in some veny high re_
taining wails. It nray be more efficient to use counterfoft type wails on the
eastern portions of the property. For design purposes we recommend using an
allowabre friction angte in the backfill soils of 35 degrees, an angle of
wall friction equal to 17 degrees and a unit weight of the backffll materialsof 125 pcf. The coefficient of sriding between the footings and the soils
should be no greater than 0.45.
;o
-11 -
The backfirl soirs will probably have to be imported. 0nsite soirs
contain excessive amounts of large cobbre and boulders and wirl be virtualry
impossible to use for controiled backfiil. The maximum arowabre size of
stone in backfill behind the retaining walls should be 6 inches. The backfill
for the wails shourd be a reasonably wer'r graded graver'y material ranging
from a maximum size of 6 inches down. clayey backfilr shourd be specificalry
prohibited by the specifications. immediately behind the uphi.lr face of ail
retaining wa's on this site, we recommend incrusion of a drainage blanket.
The dnainage fill shourd be washed gravelly sand with approximately 40%
passing the No. 4 sieve and a maximum of 5% passing the No. 200 sieve. The
graveldrainage blanket shourd be a minimum of 1g inches of thickness, shourd
be placed on the uphiil side of the wail and shourd extend to within approxi_
mately 2 feet of Lhe finished grade behind the wa.rr. The upper two feet of
backfill behind the retaining wall shourd be more impervious soirs avairabre
onsite compacted to high density. There should be an open joint or perforated
drain tile placed at the bottom of the wail to coilect any moisture that
might be co'fiected by the drainage firt. The war.r backfi.H shou]d be minus 6
inch materials compacted in roose rifts of approximately g to 10 inches to
a minimum of 95% standard proctor density (ASTM D698_70). It is essential that
the materials placed as backfilr on the uphiil sides of the major retaining
walls be carefully compacted. pracement and compaction of these fiils shourd
be under continuous inspection by a competent soils engineer.
The current building configuration shows a retaininqwarr in the middre
of each building running fn an east-west direction with a grade change of
approximatery g to 10 feet. Thj s type of construction is possible. There are
severar undesirabre effects from a structurar point of view. The wail can be
-12-
constructed as a free standing retaining wail or the buirding frame designed
with a concrete floor at the first lever and roads from this wail trans_
ferred into the frame of the structure. This type of construction is not
desirabre, but necessary on hiilside rocations. pracement of the wall and
iompaction of the filr under the best of circumstances wirr resurt in some
rotation of the wall during construction and possibly after construction.
The rotations are necessary to develop the shear strength of the soit. To
minimize the effect on the overall construction of the structure, vre believe
some serective construction techniques wiil be necessary. The best procedure
would be to construct the wans as free standing retaining warls and back_fill the wails prior to any construction above the walrs. If this procedure
is selected most of the rotation wiil occur during the backfilling process.
The wall should be detaired with sufficient ailowance for movement to mini_
mize the effect of the s't ight rotation on construction. If precast type ele_
ments are used we suggest that the detai] s be carefuily reviewed. Otherwise
it may be very difficult to get a proper fit. Backfill behind the lower
retaining wails shourd be identicar with those on the upper retaining walr.
It will be necessary to use a select backfill material . The lower wall will
be a conventional frat backfiil and can be designed as a free stand.ing wa.r
.l
for an allowable equivalent fluid pressure of 35 pcf providing select backfirl
as described above is used. A drainage Iayer must be provided on the uphill
side of the wall. If the wall is totally restrained for example, with a
concrete floor at the first level , it will be necessary to design the wall
for an equivalent fluid pressure of 55 pcf plus any appropriate surchage.
',e
have had the experience of observing this type of construction in
the vail area and the influence of these major retaining walls on construction
of simirar condominium structures. Our experience has been rather negat.ive.
- 13-
Walls of this nature are difficult to construct and contractors generally
are reluctant to follow backfilling procedures necessary to get good long
term performance. It is our opinion, that both of these walls should be
constructed and backfilled prior to initiating any other form of construction
on this site. This will cause difficulty in construction scheduling. l,le
observed construction of a similar wall in the surrner of L973 in the Dillon
area. Constructjon of the wall took an experienced major commercial contractor
from the Denver area nearly 8 weeks to accomplish for a wall approx'imately
400 feet long and ranging in height from 15 to 25 feet. 0n this site, there
are two walls of similar height. Construction shou'ld not begin until spring
runoff is comp'lete to avoid excessive moisture in the near surface layer
and local slumping. This will seriously limit the construction season. A
possible alternative and one which certa'inly bears consideration is to con-
struct the walls during the'l ate summer or early fal I of the initial season
and begin construction on the site the following season. Recent delays in
reinforcement deliveries and other problems of slope construction indicate
that these may provide major construction delays and difficulties.
Temporary construction slopes behind the retaining wal1s of 1.5 to l witt
be safe. These slopes must be checked during construction by a soils engineer
to determine if local flattening will be necessary. Steeper slopes of 1to I
may be possible however, conditions must be observed during construction to
be sure of 1to l slopes wjll be temporarily stable. The presence of the'l arge
stones and boulders will probably create more prob'l ems in the excavation
of these fairly steep slopes. Because of limited working room on the site, we
bel'ieve it wil'l be almost essential to start on the uphill wall and work
down slope during the excavation process. It appears on the preiiminary lay-
outs there may be enough working room to construct both walls simultaneously.
- 14-
FLOOR SLABS
The natural onsite soils will provide adequate support for slab on
grade construction. If new fi'l ls are required to support slabs on grade we
recommend that they be onsite or similar gravelly soils compacted to at least
95% standard Proctor density (ASTM D698-70). Materials smaller than 3 inches
should be used to place as fill to support floor slabs. In addition, inside
the building area where plumbingand other subfloor type utilities will be
placed, large materials shourd be excruded from the backfiil. l^Je recornmend
frequent control ioints in all slab on grade construction to minimize s'l ab
curling problems. provision of a 3 inch layer leveling course of sand is a
good design detail at this site. The sand layer will greatly enhance the
contractor's ability to provide a uniform surface prior to pouring slabs on
grade.
SURFACE DRAINAGE
The site lies on the slope from the high country above the building area
which drains directly into the Gore creek VaIley. During the spring runoff
periods, extensive amount of runoff flow rapid'ty downslope and across the site.
Control of drainage will be essential . If the backfills around these walls
uphill from the structures become saturated during the spring runoff period,
it is possible to initiate slump'ing or excessive pressure on the retaining
wall structure and resulting in rotation, distortion and other problems with
foundation walls. The design must include provision for interception and
control of surface drainage and routing of the drainage. we recofimend routing
of the water around and away from the foundation walls. It may be necessary
to provide surface interceptor type drainage above the major retaining wal.l
- 15-
structure and route the drainage around both sides of the structure.
Drainage details around the building irea should be carefully des.igned to
provide positive drainage away from the foundation walls. It is quite
easy to develop substantial amounts of moisture and problems part.icularly
in below grade areas during the spring when ice buildup from the winter
results in rapid runoff. These problem<should be carefully considered in
the design phases to provide for adequate drainage away from the structures.
AlI drainage must be designed to avoid saturation of the slopes and particularly
any saturation of new fills placed. The new fiil materials are very likely
to be more pervious than the natural onsite soils and s'l umping is a strong
possibility if these materials become saturated.
LIMITATIONS
0ur borings were spaced closely to obtain a reasonably accurate founda-
tion picture, variations in the subsoil conditions not indicated by the borinqs
are always possible' l^Je should inspect the completed excavation to confirm that
the soils exposed are as indicated by the borings. placement and compaction of
fill as well as installation of footings shourd arso be inspected. At this
particular site, performance of the slope is direcily related to the proposed
cuts' fi'l 'l s and inposed building loads. l.le should be advised if substantial
revisions aremade in the proposed construction.
If we can be of further service in discussing the contents of this report
or in ana'lysis of proposed structures from the soils and foundation viewpoint,
please cal l .
ROBERT l,l. TH0MPSON, INC.
By
Reviewed By
t
E0C/CRN: em
o:
^U
o
EXCEPTED LOT
{
TH4
-]
LOT A3
o
.. u,
tro
tlj,z
Faoz
a
t
I
I
IL.
PROPOSED RETAINING WALLS
o
LOCATION OF EXPLORATORY BARINGS FIG. 1
PROPERTY
""'-"-"/
JoB NO. 1698
t
r'
_!aaI
a
oI
a
I
a,aI
t
oI
I
o
3
F
f
Fa
oa
a
cLAy (2trtlrct to 3tLT (tG.rlr3yrcl
GR/\VEL 38.9 % s^No 29.2
Llouto LrMrT %
5AMPLE OF GRAVEL, SANDY,
(GM)
cLlY lr!ra:rc1 to ttl? (16-trltrct
To sr LT
PLASTICITY
SILTY FRoM
aND CLAY 3l .5
I NOEX
TH-l A 3r
7o
%
o
=
E
(\I
E
t-.o9.GR^VEL 3s.2 %
LIQUIO LIM IT
% srLT aNo cLA.z ll.z %
FLA3Trcrr.z tNoEx 7c
SILTY FRoM Tl-F 1 a 3Zl
sANo 53.6
7o
s^M FLE oF SAND, GRAVELLY,
(SP-SM)
GRADATION TEST RESULTS
t|l. I rr. .s.urrreit
a lrl ao rlt |'rn a ltt I r|{.too .sO..O.!o .[
orltETEi oF t
t. rr
rti ttLL
I {.[
?Et3
DIAII T E I O'
JOB NO. 1698 FIG.3
o
7|l. I rrc
^ar(,ltrrr6lrl aar lr rra a rtt t tr|'
OI TE Y E i
It
=!t
2
o3
a
o
_taat
t
oa
I
c|.ly IrL^trrc) To 3tL? (rc.t|.rtnc)
o
I
3
l.a
(,a
c
o:
a
I
a
:
c
cRAvEL 59. S To
LIOUIO LIMIT
SaMPLE or GRAVELT
(GP-qq)
t^to 31 .3 % stLT ANo cr-rr 9.2
% l'LAsrrcrry rNoEx %
SAi{DY ' SJLTY FRoM 1H-2 a Tl
lo
:
Eof:.
cLrY r2Lra:El ?o ttl? tro-r|'rttrcl
cR,rvEL 61.2 % sAHo 36.5% stLT Axo cLly ZJ olo
Lreuro LrMtr % FLlsrrctTy INDEX %
5A''rPLE oF GRAVEL, SANDY FRoM TIFZ A Lll
t . Irrt itrgtrntlatra aort tn a |tt. I lrr
9rattltt ot Lt rr ttLlHartrt
JOB NO. 1698
GRAOATION TEST RESULTS
FIG. 4
F
lr,
lr,,l!
I
zo
F
lrlJ
ul
83rO
8500
_ 8290
8280
8260
8250
9240
82 30
TH- 5
Er.8307'
TH-q
Er. 8308'
a
til
4sotoFII
-lT
r*'oIHIHIHI
E
83rO
8300
8280
82 60
8250
8240
LEGEITD:
GRAVEL, SANDY WITH COBBLES AhID BOTLDERS TO
6+ FEET IN SIZE, DENSE, SCATTERED T* OOT
THI CK SAND LAYERS, 3_ I GHTLY T'IO J ST I ( GP
'
GP- GtV , GM )
WEATFERED BEDROCK, SHALE AND SILTSTOTIE,
MOIST, HARD, GRAY TO BLACK
BEDROCK, I NTERAEDDED LII4ESTONE AND SHALE,
VERY FARD, FM I ST , GRAY TO E]I-ACK
PRACTICAL DRILL RIG REFUS_ WITH 4 INCH
HEAVY DUTY AUG€R . T"IORE THAN ONE SYMBOL
II.DICATES DEPTH IN ADJACENT f f)LE ATTETVPTED
AT SAME LOCAT ION.
INDICATES LENGTH OF '' NX '' (2.I25 INCH DIAI!,ETER )
SIZE CORE RUN. MJMBER INDICATES PERCENT OF
SAMfuE RECOVERED FOR LENGTH CORED.
DRIVE SAI,IPLE, TI-E SYMBOL 25,/6 INDICATES
THAT 25 A_OWS OF A I4O POTAD HAIf,4ER FALLING
30 INCF€S WERE REOUIRED TO DRIVE A 2.0 INCH
SAI.'IPLER 6 INCF|ES.
l€TESr
(I) AORINGS WERE DRILLED JTJ|.IE IO_I2. 1974 WITH A 4
INCH MWN_TFE-FOLE AIR PERCUSSION HAIVI4ER POWERED
BY CME55 DRILL RIG AND A 5OO CFM AIR COMPRESSOR.
( 2 ) TI-JE BOR I t']G WFERE SH]IYN WAS coRED WITH AN I' Nx II
SIZE DIAMOND TIPPED CORE BARREL USING AIR TO REPNVE
CUTT I t\GS FROM TFE 8OR I t,lc .
( 3 ) NN FREE WATER WAS FOUT\D I N TFE BOR I I.IGS AT TFE
TIME OF DRI LL ING.
TH- 4
Et.8305'
2t /t2 50./0
25lO
TH- 2
Et.828t'
F
TH- I
Et. 8274
20/t2 43/6
23/?
20/6
?5 lO
TT
T
T
u/6
t5/6
,a /7
20/a
t4 /6
?t /6
to/o
F
IrJlrlE
I
z.o
F
lrJJ
lrl
( 4 ) [:LEVATIONS WERE FL.,RN I SHED BY FRASIER
CINSU-T IllG ENGI I\EERS.
AND GINGERY
JOB NO, 1698
35/5
LOGS OF EXPLORATORY BOR INGS
FIG. 2
se*l
tt tI t. rF ii tt!:1i,{ili4:lil
a
SPECIAI, DtrVELOPitlE:IT DISTRTCT
. DAlr-{\ - (i!{!-rls1roFtlEtl xarcltrJta.R cHr:tr3$c1r
ae6a 6.0Trg. lfElt\rElrn.co.ese.g---I
+-ownhou:it condoniniums irr 7
13.30? acr. es loc.tted. in
A planned unit developnent containing 26
'buildings ancl 4 resident,ial units all on
Llon sr j.dg€ subdi.vision.
gliliEnt'
Sky I ion "partners at VaiI,
A Colorado Corporation
312 University Boulevayd,Colorado B 0?06
Co lorado
Denver,
?\ i? a u T na r.'a'F .
Dana C. Rickl-i
2 3 fi 2 Soutir OL.is
Dcrnvcr, Colorado
$j!c_!!rns:
Ginqery and
?Orn C..rr+?,
Iing l ewood ,
A ssoc ia te s
Colorado 80110
)lrJ "rr', L.ltrl I\t-Llr.:
5..!t. Thonrpson, Inc.
17 01" S. Fe,.rleral. IlIvd.
iienver, Colorado I0219
i
I
I
I
I
I
I
I
I
l
I
i
I
I
Oo
;
-rHE SI1E:
oo
l
.'The site, a triai.lgular shape, is
corner of Lionsridge subdivi s ion
of which I0 acres o are treelese
'and. shrubs (see exhibit "A"). It
Forest on the north and uest and
A platted roadway (Lionsridge Loop) has been
revcgatated several years ago and it has no
?he- topography is sloped from 3Ot (19'in 3OOr) to 70?
qrest to east. The elevation ranges fro.n 8230r to g59O'
developed area is between 8250. and 8340, (see exhibit
cut, refiLlad and
access to other roads,
(100r in 30Or)
but the
B, and c^)..r z
{.ITT I. T? I ES Arib st;RvrcEs
Lions Ridge ifater.Dlsericr isee exhiblt
s^f is l0catecl in a. 6n main al0ng the north side of sandstone Dr.
''
I
!
I
I
be
g-l-gsg.!q service is avairabre on the north slde of snads+-one Dr.
",,'hcre 3n existing vault is located (see exhibit "o" ) . An alr:ve
(;round trans;nission. line clgsses the property lrest to east from
50'to 1.00' south ff the trce line at elevation g3S0. to g410,.
This i.s a nain feeder to the town and.is. to remaln.
l.:.1r i s :rva iIaI_.Ie in a
av.ri labl e for discharge
avaj lable for this project.
rirg-l-lg\s{lg service has been
" Iine in Sanditone Dr.
(see cxh ilrl t "O" )
marrhol es .
thls subdivision.
this developnent
vla the new
rnunicipally
br. and gas
with
Lttility Plan
.'
ca.i linr. ic rlcn l^-
a
Bus Scr)avice
Aut-o access
is projected to be
is ava 1lable
recently extended. tb
a-vailable in l9?7 for
and to Lionshead... 'on Sandstone Dr. to thc village
Periestr ien access
:rc(j(.:strian bridge
will also be availhb]c to Lionsbead
to be constructcci in 1.97?.. -
on Sendstone Dr.whlch is.
'cr
na in!a itlcd
See
, . ".-i,*
s creet
I I
aOoo
TTIE DEVELOP!'TENT:
26 townhouse condominiums in 7 buildlngs .of 3 and 4 townhouses each
are planned.. Each tor,fithouse sill have a 2 car garage and entry
vestibule on grade and include 3 bedrooms, 2l baths, kitchen, dining,
and living room and storage area. Parking adjacent to garage for
two adclitional cars will be available. (see exhibit ., , )
Consturction will be frame with stained wood siding. Roofs r,rill be
r*ood shingles. All glass rpill be double patre, wood f rarned. Iieating
_systems will be electrie or gas hot water wi.th posaible heat pump/
solatr.assist. Domestic watcr .will be solar heated using roof, top
colleceor. Insulation will be 5" (walls) and J.2t' (roof) batts to
provide R-19 and R-40 ratings for walls and roofs (see specif i.cations
exhibit
A]so to be
cuI-du-sac )
rni n inurn of
).
inctudecl are
which wi 11
2 car garage
sites for 4 private residences. (2 on each
be up to 4000 sg.ft. each mqximum. with
and parking for 2 additional vehicles.
Specifically, these house6, nirile not prc<lcsigned, shaIl
rvith tire townhouses in material .and finish by covenant.
These uni+-s shall be desiqned wi!h solar domestic hot water
and possibly will havo solar-assisted heating systcms.
ba corn!ra tab 1e
sys t ems
?rash disposal will be handled
anticipaicd that each unlt will
col lector bins wi I I br-- screened
on. a por buiJ-ding basls
have a trash compactor.
in an area adjacent to
"l
and it is
Larg e
each bu i ld ing
h'ith f,enci.ng and plantinge.
' - _| .'
A pavecl road syste. or 25' aspharb wirl be irnmedi-t.rv aciacent to
all units and r:rovide direct aece,qs to crar<1qes. Roads are
<iesigned to i:ave a maximurn srope of lOt and since this is a .south
facinq slope the necessity for heated roaclways is'eliroinated.. These
rords will ba maj-ntainccl by tire resident adciociaLion on a joint
b.r.sis, as will the trash re:noval
The townhouses are to be sold through a Chieago based
on a time-share basis. The anticipation is then of a.
poprrlation which woul<1 not chanqe school projections,
j.ncreasing the tax base with mininum impact.
sales of f i-ce
+*--- i ^-!r-.r-crrl-_t.!rj.rL
substant j.ally
The rcsidential sites tnay have permanent re.sidents but four familj.es
with the u.s. average of 2.3 childr:en per household will only total
9.2 chj.ldren to add to Lhe presenc school population. A combj-ned
tdivn bus stop/school bus stop Kiosk is pranned and wirl be located
near the intersection of sandsLone Road and Vail view Drive.
construction is anticipated on site work (r:oads, utilit.ies) in
i,:a)', 1977 and btrilding construclion to bcrqin as soon. as access
boconres possible thereafter. one townhouse building at a time
be constructed as nurnbered on site development plan.
late
to si t-es
sir.r ll
ff salcs dictate, additional units may
cornplete buildings will_ be built. It
and roadwork will be cornpleted.during
be built sj.multaneously but
is anticipated t,hat all ut.ilit.y
the 1977 building season.
QUi\l';'rITAjlM DESCIiIPiION
Toisl .Acreage
tlisting Zoning
Proposed Zoninq
ia'.*nhouses:
13.307 acres
:
RC: 2;596 + .944
A: 9.767 . ''i i. ---r/
S.D.D; with
a. ..
3.54'(- -:-i aeres
. -r.J
100'
4
t.t
I
'Uax. 4000 t{
' Same
. [Iax, 16000 g
'l'lax 40OA fl
5
4.
A;8.909 acrcs
i':c;pc,:;r:d Usage':
Buildings
Units,/Buil ding
Total. Units
7\ F.rl /tlrr i t..t v qil vr.4 e
Toeal Area
Tota.l Ground cover,/Unit . ." .
Total Ground cover,/Building
ToLaI Ground Cover ' .- :-
Maximurn Height of
Average lleight of
I'taximum Length of
tleximum Lengt.h of
Buildings
uni tslBui lding
TotaI,/Units
Arca,/Unit
Arear/Building
Total Area.
Ground Covcr/Unit'
|.t.I
i
Un it
Bu j.]dinq
Ii,-.r i ,i? rlrn J. i :.r 1 .
l
]
School Age Children
Vehicles:
2/uniE
Residences
'Townhouses
. Residences
:'
'!
i
i
.,
.I-I{P GEOLOGY
l::j.s repcst, made in the suftner of 1974, specifically for..site A-3 is
:)r'eenter: of the proposed develope<l area and its findinqs can tre
i.ntcrpolated for the areas east .and ',,rest since the contiguous
.:r.r.'eloDnent is on ther same geologic base with similar slope and
charact-eristics. S)-iqht variations a{.e possible even within the A-3
!iiLe boundaries buc rvith inspection by the soils engineer at the
vlri.ous excavations and buts nade for roads, ut.ilities and foundations
anv rrariat.ions discovered mav be accounted for in ammended desiqns
i):; recorrunended by the soi.1s engineer.
The rcport notes as average
and of an uncleveloped nature
A construct.ion road irad been
cr;uipi,rent
a[)l]cltr possible.
Thcre are no topogroi>hical
j.s opposite to the slope
or veg{tatjrnfffu,indic.rtions that there is
slope of 2,5:1
with a fairly
developed to
(horizontaL
even sloge
allow access
to veritcal.)
across the si te.
Fat Asl lIiF^rJ-.|-!:rY
'lhe siLe lies below the upper lirnits of gl.acial activity and the
enuire surfacc within tlre site indicates glacial material, wit.h
oirtcrops of sedimcntary forinations located higher on the slope above
tl:e investi<_lated sitc, and to the west and south west at elevations
.: rnt rnuous wi th elc,vati ons in the investiqated site..
The slope of the sedimentary fornations
of t.he vallcy. The natural vall-ey walls are a rcverse slope to the
st'rdinrentray for:mati.ons, Lherefore bedding plane slippacye does not
i
t.E F ,.,tface watoralonq thc'east portion of the total aeiea,re. iher:e 'j.s'
l. ' "i"al: r r 11111,1 areA On tire etst ed.:e of lot _l\-l and t-ho tr'F!:t .:r_tr!.' 11f
t
tt ;..-Z with treeg and brush nhich indicate.'run off concentration
t-, .l::--h r.'? r:r;::t- i:,:rl uiLh by containing and.diVerting wherc roads
' lrrverse the arca.
, 'l'::r) .r:rajoriti, of rain or snohr nelt water is
'.r.:iter clue to the angle of the site.
'i,.to t!.'pes oi- subsurface roaterials were encotrntered: (l) glaclal
.iibris and (2) r''eathere<l bedrock, both of varying, thickness.
80', No free watcr
the ti-rnc of drilling
carried off as surfacc j
was encountered in
for 3 <lays after- :
-+
I;lrCrock depth wag 29' to I
!.iry of .ti:e test borings at
i'I..r ?-.r:t <1nn4 iS Stabel with a. J. r rlvl-r
| (1.9 to i.3).
5:iiice the analysis was based
).:i-tinr; and retaining vre feel
<Jc",'cl1op-rnent should have even
r-:ilrefore be equally stabler
corlccived usinq 4000 psi soil
no longer of in"'nportance. "
relatively high factor
on a design which reguired extensive
that the easier design of the present
Iess effect on underlying strata and
with spread footings as originally
Pressure.
Ite anticipate no use of high retaining walls on the projected
cl,.-.sign 60 nost. adverse corxnents in the report concerning those are
be utilized arounclllerouting and control of surfaee drainage must
:
I
":l!'lletion
, :,.-'^I 1,_, '.1u
I !.., r- :l i n.l.te!t.r.- . \. e$- -
to effectiveLy s,tabilire these areaE and interceptor
r:.ust be install.eC irt thcse locaticns (founC:tlo:rs
area s )
,t,
lr
i' r)-r l:J
t,
.l',i..'g*;j
no'v, serves onJ-y Cif project
The .Lionrs Mane project- of
t,, '"i. ;1 1-*s61;h€f,Q:
i'
r, jr rl ': r r-(i lle ur'
cl: I-cu-sac end
: : .r tossible
,t.-
(upper porLion)
on the west.
population of
and has
Units
.. .: j-,rcpsi;red developnent is being conceived as a time.share
.r ':::lio:iiniu:tl prolect and wiLl be owned by oqt-of-town non-permanent
:,..:;iiicnbs who historically, in Vail, have eome to town via maos
,r'r;s1t systems (air or bus) and utilize private development parking
.rt s 3C-401 rate of capacity. (ie: gurvey by Vail Associates made in
''-.i't-:rber 19?3 for Lionshead)
"'.rng this as a basis, our
!. 1 351 of a total provided;
- t I't:h i cles .
cars, by Vail regulation ratj-os.
capacity at any one time would
=50 x .35-)'provinq to be
project-ed
(30x2
:':'::ICrr woul-d alipear to be the season $rhen the maximum vehicles wil.l
iic !):'esent and this colncides $rith the lower rates of total
''.:ci.:I)a!1c:/ for the valley and the greater availability of parking
:i, M:":lcteci areas of the town.
par)":ing, bus availabillty and close proximity of the
briige all lead to the. belief that even the 2l vehicles
would be under-utilized thr further miniuizing.their
the valley as a whole.
are p;ojected 4onl'y alone. per unit baeis therefore a totalI'J.l'epl.rce..s
Irt,I
.E
. F'..s.
I
.t'
rr
i..
I
i
, D ..- -9,
. i !'1 (3uld
- ' ! ^..: thi' nnturat, wind* to'caffy 'the snoke generated alof t;and
.; .:, I cc.ruLd be electriC
i:r Lhc cualitY units we
or ga6
hope to
type but especially
I
It
1
source capacity is
a requj.reil
suPply sl'stem
rr;'n tlOl,OGICA.t',':.:j:*-
?he area.now. is a aurface ru.n off area and the development wl1l not
,rl-rer the natu::al condition, but will present some additional
,'.
':pervious surfaces, but with filL from other areas a probabl
r:,:c..:ssity, the more permeability of these areas coul<l offset the
r.oads and building areas. Besides the roadways will have gutter areas
;r)ii.ch will channel their runoff and in effect lessen the total run
cff on the exj.sting soils by transmitting the runoff to tbe base of
r::-: site directly.
'.i.ricf and sewer liFib€ are readily accessible and
.riicqu:rtr:' for the projecteJ <levelopment.
ri uater storage tank with purnp wiLl aid i,n naintaining
,:cad of water pressure and act as a reserve should the
l;e inoperative for any reason.
li'.irants (5) are
IoertionS within
to be provided for fire department use
the development.
at canvenient
!
i
t-
lt
t
t
f,
Ii
Additional
unit for a
and at road
+landscaping will be provided on a basis of :1000 per
total of $251000 for trees around and between buifciings'
:-oUtS. ' tt
?he deuelopment, abdve the other larger bulldings jn thc
. . area, wi1l, present a. Ioosely defined edge for development
' extends toward the tree line above. and Eire forest service
. tl:r: ea.st and west.
.1'! .. :
Lionstted,i*r:.. '
!
as it
lands to
The easing of the abrupt zone of
lands wi1.1 be more natural .than
developed area with the fcrest
thc conditions which now exist.
Thc developers rsirl revegetate the ar:cas cut previously for sitc
studies and also blend the new construetloh, with the site thru
use of compatible colors and materials and use 6f natural materiaLs
at areas where they are disturbed'b)' construction. .
..
The developrnent r^rirl. present some of the finest vier.rs of the, totar
valley while the srnalr scale of the units (25') ancl their ioif,,i,
diagonally wirl presents a faceted appearance wlth many offsets on
a-lr f acacies, as vrill the varying roof rincs possible by having
as .nany as 3 different. entry elevations rvith each buirding. ,
I Jr:ie io Sept.30..'tL977
'1 June to sept.3o, 1977
1 June to'l
*l Building Excavation:
Sent. 30 ,ent. 30 r t977
6 per development Plan tt:15 July r 1977 toBu!ldingsr Sequenced as
ntl.FT.Tr.rF a DF/r tF Y^n4r trrrlc
SKYLION TOWNHOUSES
arn tt a-n t n ftl t\/1v tt ^u, \, \., IJ \,r. \J r lJ l\,
1. Foundations:
xllD
Refrigarator:
Modernmaid
286/NBC. 230
GE 14 cubic foot
..rs'.'-' -r':l'-Ei t -:'3tr:gli:. .' ;{L-t-
frost free with ice
:'
S1>read Footingst L2r tlrick (sizes vary)
Fia1ls: 8" thick with t4 ? I2'. E.l.I.
'.::-Grade I,laIIs: 8'' thick with.2-#5 top and bottom
' Floorsz 3/4" plywood on 18" TJlrs I 24n cc, carpeted
Walls: ! Gypsurn board on 2x4 and 2x6 framing, painLed
Paneled, 5/g type x at garages
Cabinets: Prefab, solic1 wood doors, oak, prefinished
Stove; Oven; Dishwasheri Ductless llood: Freestanding
Etectric DCt 422,/NDw 560 Combination unit.
3. Doors,
4.Kitchens:
Ceilings. *rn gypsum board spray textured
l"IinCorvs;
Sliding Doors: 510" x 6t8" wood
Exterior Doors z L 3,/4" solid,.core, glazed, painted
.
Interior Doros z L 3/4" solid core oak veneer stained -
Bifold Doors z L L/8" Flush oak veneer, stained
Ilirrdows: Wood sliding , 4'O' x 4 | 0' ,' 2'O" x 4'0" and
' fixed, aLL 5/8" insulated glass with storm
panels
oa
'r, .\. :,..,' -. .i.\ ..
-,\
OUTLINE SPTcIIJIcATIoI.Ig
Disposer: l,lodernmaid,XttD-450 lhp
Sink: 18" x 20' stai.rrless steet (air gap for
dishwasher) with spray and single leve} faucet
tops: Plastic Laminate with 4,, p..L. splash
3 sides and bar.
: Cast iron 30" x 60"
3 wal1s around tub
with showerr. cerarnic tile
Lavatory: oval 18r' cast, iron bowl with single lever
faucet
Stool: China floor mounted, watcr saver
ilot I'Iater Heater: 50 gal, electric
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SKYLION CONDOMINIUITIS
VAIL, COLORADO
'Counter
5. Baths:
6. Ileat.ing
7 . Utilities:
Fv+A?in?.
L rIlJ
type
Apar:trnents: Base board electric, resistance
vrith individual thermostats each room
vidual meters for each unit)
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(inc1i-
ffater: connpcted to municipal trater 'systern
Sewer: connected to municipal r!'as te system
Eleetric: llolycross Electric Co. service (uncler-
grouncl)
si<ling: . 5,/B! pJ-ywood (textured) wLth pine
.
trim, sta.ined
Open Railinqs.: 2x4 at 10" cc uith l8' plywood bop
rail,2x5 trim
8.
Wallsr 'R 16 batts
Foundations
Ceilings: R 30 batts in
I" etyrofoarn
joist spaces
sheatrng
'7
..:. ..,
ac
i1. IialIs Franing: .
2x6 at ]6" cc exterior structural 2x4 at 16" ec
elsewhere - Plur'rbing walls 2-x 6 at 16" cc
a
l ) I '! hr t:l\.1-.
. . -?-
Fl n.rrq. c;rr'':rrt - sheet vinyl at baths; quarry til.e '
a}1 +rrttillL.|-)r
'Base: I k" wood ,.'.'.'''.'
IlaLls:
.
A. 'Light texLured drywall, paj'nted {enanel
kitchen and baths)
ts. Panelecl rvith Br:ookswood 3/4" T&G (n.S.l
C. Ceranic Tile at tubs
Ceilings: Ileavy sPraY texture on drywall .
All v;oocl interior to be natural or stainecl and shellaced
Alf exterior t:ood to be stained or sealed
13. I",andscaping: slOpes to be covered with native rocks with
I ^-.-iplanting areas of evergreens and aspen
li. Special IJquiplnent:
Sinoke Detectors: each unit at bedroom halls and garage
Fire system: Buildings will be tied into Vait !'ire
Station with teLephone signaL alarn,
Telcphone: Ono rough-in provir.led for each unit
Fireplaces: Prefabricated Metbl-bcstos 1i-tn double-
' walletl netal flues raised hearbhs with quarry
rr i "Jot ?l,rNE SPECIFICAfIONS
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, SKYLION EONDOMITTTUI{S
VA.IL, coLoRADO
' tile sutface and woocl edgee' ^ . . . :
Each unit to hiVe two garage spaces and two other
'.'rparking space
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.
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Fl lect.'" r ,.
sqiisi-r! rlf til
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ir.itr.,"
l. .,...-'..
45,0C0
' 25r 000
)\ 2't1
17, 800
25, ooo
50,000
__i.-L i,30_
207,677
'c tt
Jr*;,i:n&,^7*
ORDINANCE NUMBER
DISTRICT NUMBER
Series ot L976
AN ORDINANCE ESTABLISHTNG SPECIAL DEVELOPMENT
DISTRICT 8 AND AIVIENDING THE ZONTNG ORDINANCE
AND THE OFFICIAL ZONING MAP.
WHEREAS, ArticJ.e 1, Section L.201, of the Zoning Ordinance,
Ordinance No. 8, Series of 1973, of the Town of Vail, Colorado,
as amended, established thirteen zoning districts for the muni-
cipality, one of which is the SPECIAI DEVELOPMENT DISTRICT.
WHEREAS, SKY LION PARTNERS AT VAIL, a Limited Partnership,
submitted as owner an application requesting that the Town
establish Special Development District 8 hereinafter referred to
as "SD8" for the devel-opment on its parcel of land comprising
13.307 acres in the portion of the Lionsridge area more fully
described ag Lots A1, A2, A3, Excepted, L,ionsridge Loop R.O.W.,
and unplated area north and (above) of Lionsridge Loop R.O.W.,
resubdivision of Block A, Lionsridge Subdivision, County of
Eagle, State of Colorado, which was annexed to the Town effective
on the l6th day of December, L975.
WHEREAS, the establishment of the reguested SD8 will ensure
unified and coordinated development and use of a critical site
as a whole and in a manner suitable for the area in which it is
situated.
WHEREAS, the Town Council considers that it is reasonable,
appropriate, and beneficial to the Town and its citizens, inhabi-
tants, and visitors to establish said SD8;
NOW, THEREFORE, BE TT ORDATNED BY THE TOWN COUNCIL OF THE
TOI^IN OF VAIL, COLORADO, AS FOLLOWS :
Section l-. Title
This Ordinanqe shall be known as the "Ordinance Establishinq
Special Devel-opment District 8. "
Section 2. Amendment Procedures Fulfilled; Planning Corn-
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mission Report.
o
The amendment procedures prescribed in Section 21.500 of
the Zoning Ord.inance have been fulfilled' with the report of
the Planning Commission recommending the enactment of this
ordinance.
Section 3. Special Development District 8 Established;
Amendments to Zoning Ordinance and Official zoning Map.
Pursuant to the provisions of ArticLes 1, 13, and 20 of the
Zoning Ordinance, Ordinance No. 8, Series of 1973, of the Town of
Vail, Colorado, as amended, Special Development District 8 (SDB)
a special deveJ-opment zoning district, is hereby established for
the development on a certain parcel of tand comprising 13.307
acres in the Lionsridge area of the Townr and the Zoninq Ordinance
and the Official Zoning Map are hereby amended by the addition of
the following provisions which shall become the Chapter of
Article 13, the caption of which shall be "Special Development
District 8, " and a map which shal1 become an addition to the
Official Zoning Map:
A. Purposes.
Special Devel-opment District 8 is established to en-
sure comprehensive development and use of an area in a manner
that will be harmonious with the general character of the Town'
provide adeguate open space and recreational amenities, and pro-
mote the objectives of the zoning ordinance. The development is
regarded as complementary to the Town by the Town Council and
the Planning Commission, and there are significant aspects of the
special development which cannot be satisfied through the impo-
sition of standard zoning districts on the area.
B. Special Development District 8 Established.
(I) Special Development District I is established
for the deveJ-opment on a parcel of land comprising 13.307 acres
in the Lionsridge area of the Town; Special Development District
8 and said 13.307 acres may be referred to as "SD8."
-2-
t2) The land shall be divided into two develop-
ment areas called A and B. Development Area A shall consist of
8.909 acres including the unplatted area' a portion of the right-
of-way (abandoned Lionrs Ridge Loop), and the excepted Lot and
sha1l be agricultural in nature. Development Area B shall consist
of 4.398 acres, including Lots A1, A2, A3 and a portion of the
right-of-way and shall be residential cluster in nature.
C. Approval of the Development Plan Required Prior
to Development.
(f) Before the developer conrmences site prepara-
tion, buiLding construction, or other improvement of open space
within SD8, there shall be an Approved Development Plan for said
district.
(21 The Proposed Development Plan for SDB in
accordance with Section D hereof shall be submitted by the de-
veloper to the Zoning Administrator who shall refer it to the
Planning Cornmission, which shalL consider the plan at a regularly
scheduled meeting, and a report of the Planning Commission stating
its findings and recommendations sha1l be transmitted to the Town
Council. in accordance with the applicable provisions of Article
2L hereof.
(3) Upon receipt of the ProPosed Development Plan
and the Planning Commission Report, the Town Council shall deter-
mine whether the plan is acceptable to the Town in accordance with
the applicable provisions of Sections 21.505 and 21.505 hereof.
(4) The aforesaid determination by the Town
Council shall be made through its enactment of an ordinance amend-
ing the provisions of this Chapter in an appropriate manneri in
the event ttre Proposed Development Plan is approved, it will be
incorporated herein as the Approved Development PIan.
(5) The Approved DeveloPment Plan shall be used
as the principal guide for all development within SD8.
(6) Amendments to the Approved Development Plan
which do not change its substance and which are ful1y recommended
in a report of the Planning Commission may be approved by the
Town Council by resolution.
-3-
(7) Each phase of the development shall reguire
the prior approval of the Design Review Board in accordance
r^rith the applicabl.e provisions of Article 15 hereof .
D. Content of Proposed Development plan.
The Proposed Development Plan shall include but is
not limited to the following data:
(1) The Environmental Impact Report and a sup-
plemental report for each phase of construction which sha1l be
submitted to the Zoning Administrator as may be requested in ac-
cordance with Article 16 hereof.
(2) An open space and recreational plan suffi-
cient to meet the demands generated by the development without
undue burden on available or proposed public facilities.
(3) Existing and proposed contours after grading
and site development having contour intervals of not more than
two (2\ feet if the average slope of the site is 20 per cent or
less, or with contour intervals of not more than ten (I0) feet
if the average slope of the site is greater than 20 per cent.
(4) A proposed site plan, at a scale not smaller
than 1 inch = 50 feet, showing the locations and dimensions of
all buildings and structures, uses therein, and all principal
site development features, such as landscaped areas, public fa-
cilities, pedestrian walkways, driveway, and off-street parking
and loading area.
(5) A preliminary landscape p1an, at a scale not
smaller than I inch = 50 feet, showing existing landscape fea-
tures to be retained or removed, and showing proposed 1andscap-
ing and landscaped site development features, such as outdoor
public facilities, trails, pedestrian walkways, and other ele-
ments and methods of reveqetation aL cuts and utility.excavation.
(6) Preliminary building elevations, sections,
and floor plans, at a scale not smaller than 1rl8 inch = I foot,
in sufficient detail to determine floor area, gross residential
floor area, interior circulation, locations of uses within build-
ings, and the general scale and appearance of the proposed develop-
ment.
-4-
(7) A proposed plan of parking, loading, traffic
circulation, and transit facilitiesi and a proposed program for
satisfying traffic and transportation needs generated by the
development.
(8) A proposed preliminary plan for any utilities,
such as water, sewer, gds and electric, which plan shall desig-
nate easement areas and conform to the usual specifications of
the approving authorities of such utilities.
(9) A preliminary interior road plan providing
ingress and egress, designating appropriate easements, and re-
guiring less than 10 per cent sl-ope throughout the area.
(10) A volumetric model of the site and the pro-
posed development, at a scale not smaller than I inch = 50 feetr
portraying the scale and relationships of the proposed develop-
ment to the site illustrating the form and mass of the proposed
buildings.
(11) An architectural model- of each proposed
building, at a scaLe not smaller than 1 inch = 20 f,eet, portray-
ing design details.
(12) A proposed program indicating order and
timing of construction phases and additional amenities.
E. Permitted Uses.
(1) In development Area A the folLowing uses
shall be permitted:
(a) Single family residential dwellings;
(b) Public parks, recreation areas and
open spaces.
(2) rn Development Area B the following uses
shall be permitted:
(a) Multiple family residential dwellings.
includingattachedorrowdwetlings,andcondominium
dwellings.
F. Conditional Uses.
(1) rn Development Areas A and B the following
conditional uses shal1 be permitted, subject to issuance of a
-5-
Conditional Use Permit in accordance with the provisions of
Article 18 hereof;
(a) Public utility and public service uses;
(b) Public buildings, grounds, and facili-
ties,
(c) Public park and recreation facilities.
G. Accessory Uses.
(1) In Development Areas A and B the following
accessory uses shall be permitted:
(a) Indoor and outdoor recreational faci-
lities, including but not limited to, swimming
pools, tennis courts, and similar recreational
facilities.
(b) Home occupations, subject to issuance
of a home occupation permit in accord with the
provisions of Section 17.300 hereof.
(c) Other uses customarily incidental and
accessory to permitted or conditional uses, and
necessary for the operation thereof.
H. Development Standards.
The following deveJ.op:nent standards have been submitted
to the Planning Cornmission for its consideration and recommenda-
tions and are hereby approved by the Town Council; these standards
shall be incorporated in the Approved Development Plan pertinent
to each Development Area to protect the integrity of the develop-
ment of SD8; the following are minimum development standards and
shalI apply unless more restrictive standards are incorporated in
the Approved Development Plan which is adopted by the Town Council.
Development Areas may be modified, provided that no such modifi-
cation shall- increase the discrepancy between the structure or
site improvements and the development standards set forth in this
Article for the Development Areas.
(l) Lot Area.
Development Area A shall consist of approximately
8.909 acres and Development Area B shall consist of 4.398 acres.
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(21 Setbacks.
The required setbacks shall be as indicated on
the Approved Development P1an, being a minimum of 2Q feet from
any perimeter property line of the total site.
(3) Distances Between Buildings-
The rninimum distances between all buildings on
the site shall be as indicated on the Approved Development Plan,
being a minimum of 20 feetr provided that 1 foot of additional
separation between buildings shall be required for each 2 feet
of building height over 15 feetr calculated on the basis of the
averagle height of the buildings. This sha1l not preclude buifd-
ings from being connected by enclosed walkways.
(4) Height.
The maximum height of all buildings shall be
25 feet Area "A" and 30 feet Area "8."
(5) Density Control-.
The floor area of all- buildings and number of
dwelling units sha11 not exceed the foltowing provisions:
(a) General DensitY PIan.
DeveloPment DeveloPment
Area A Area B
l4aximum gross GFRA shall be less than GFRA shall be less \
residential or equal to 4000 square than or equal to
floor area feet per dwelling unit 1842 sguare feet
(square feet)
Maximum number 4
of dwellingunits
per dwelling unit
26
TOTALS 16,000 square feet 47,894 square feet
(6) Building BuIk Control.
Buil-ding bu1k, maximum wall lengths, maximum
dimensions of buildings, and requirements for wal1 off-sets,
shal1 be as indicated on the Approved Development Plan; provided'
however, that said standards shatl not be less restrictive than
the specifications under Section 12-506 (s.F.R.) and 23-505 (R.C.).
(7) Site Coverage.
Not more than 5 per cent of Development Area A
and 10 per cent of Area B shall be covered by buildings.
(8) Useable OPen SPace.
(a) Useable open space for residential
cl-uster dwellings shall be required as indicated on the Approved
Development Plan, but in no case shall the useable open sPace
requirements be less than the following:
A minimum of 500 square feet of useabJ-e open
space shall be provided for each dwelling unit in Area A, and
350 square feet for each dwelling unit in Area B.
(b) Useable open space may be common space
accessible to more than one dwelling unit, or may be private
space accessible to separate dwelling units or a combination
thereof.
(c) At least 50 per cent of the reguired
useable open space shaLl be provided at ground level' exclusive
of required front setback areas.
(d) At least 75 per cent of the required
ground level useable open space shall be common space' the
minimum dimension of any area qualifying as ground level useable
open space shall be 10 feet.
(e) Not more than 50 per cent of the useable
open space requirement may be satisfied by balconies or roof
decks; the minimum dimensj-on of any area qualifying as non-ground
level useable open space shall be 5 feet. and any such area shall
contain at least 50 square feet.
(9) Landscaping and Site Development.
A rninimum of 60 per cent of Development Area B
shall be landscaped in accordance with the Approved Development
Plan. A minimum of 95 percent of Area A shalI remain in its
natural slate.
(10) Parking and Loading.
(a) Off-street parking shall be provided
in accord with Article 14 of this ordinance; the required parking
shall be located within the buildings. or beneath accessary decks '
-8-
or terraces, and shaLl- be compJ-etely enclosed and screened frorn
view.
(b) No parking or loading area shall be
Iocated in any required front setback of the Special Development
District, and no parking or loading shall be permitted at any
time in areas designated for recreation or open-space use on the
Approved Development Plan.
(c) Driveways, passenger loading areas, and
parking areas not located within a building shal1 be permitted
only as indicated on the Approved Development Plan-
I. Recreational Amenities Tax.
The recreational amenities tax due for the development
within SD8 under Ordinance No. 2, Series of 1974 of the Town of
Vail, Colorado, shall be assessed at a rate not to exceed $0.25
per square feet of gross residential floor area and shall be paid
in conjunction with construction phases and prior to the issuance
of a building permit.
J. Limitation on Existence of Special Development
District.
Prior to the adoption of the Approved Development Plan
the Tohrn Council reserves the right to abrogate or modify Special
Developnent District for good cause through the enactment of an
ordinance; provided, however, that in the event the Town Council
finds it to be appropriate to consider whether to abrogate or
modify, the procedures shal1 be in accord with Section 21.500
hereof.
K. Conservation Controls.
(1) Developer shall include in the building
construction in Development Areas A and B energy and water con-
servation controls as general technology exists at the time of
construction.
L. Additional Amenities.
Developer shalt provide in its approved Development
Plan a bus shelter of a design and location mutually agreeable
to developer and Town Council. Said shelter to serve the Lions-
ridge area generally for regular and or school bus service-
-9-
';:L)i::----. :. :" - a
!1. solar utilization.
Developer shalL provide for solar utilization in
building designs where they prove to be feasible and readily
available such as for domestic water heating and or building
heating.
N. DeveloPment Control-
The Developer shall retain controL over the progressive
construction of site and building improvements to see that they
meet the restrictions set above and as may be amended and shall
be responsible for carrying out the intent of this development in
a manner acceptable under these above tems.
-10-
App I i
Hea r i
c,I tnS l
At,r'L i c^r I ol1,,r;if: u^', i
^rror-
c0NDll l0i,1AL. tillI PIRMll'
0rdinance I'l o. E (St:t-ies o I l913)
cation ,"rf lOl4l% ..Pub I ication ,,,ru-fufi--
,lr I
ns Da r. y'litu. ? learin1- ,." lOO." ld,
Dec i s ion da1'e for Town C<:uncit
( Add ress )
( vre )
pnone ?/t7-u-ll
(State) (City)
do hereby request perrnission 'to appear before the Vail Planning
Comm i ss ion to req uest 'l lre f o I lot^r i ng:
) Variance {rom Article , SectionX zonins change rro'KC;FA-'t" 5F-) Parkino Variance r
) Cond it iona I Use Perrr it fo allow
in Zctte.
Clearly s1'ate p u rpose and intent of this applical'ion
For the folloviing described properfy: Lo'i,/tract lrZrS* , atoctAtEiStl
Fi iins Numbe , LlA$Ctr(l'|(te # |
(Applicant)
lirt^lP.
WhaJ' cio you {eel the bas is f cr trardsh ip th is case?tn
5i ii1 rl itrr
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SKY LION SUBDIVISION
VAI L, COLORADO
PRELIMINARY
DRAINAGE STUDY
Job No. 752.012
August, '1975
Prepared For
Mountai n Properti es , Ltd.
Chicago, I'll inois
By
Gingery Associates, Inc.
Englewood, Colorado
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SKY LION SUBDTVISIONvArL, COLORADO
DRAINAGE STUDY
Job No. 752.012
August , 1-975
TABLE OF CONTENTS
l L. General
r rI. Area Description
I rrr. criteria
IV. Calculations
I v. Proposed Drainage Study
I VI . Surnmary
r vrr. Figures
I Figure I Vicinity Map
r Figure 2 Rainfall Depth - Duration - Frequency Graphs
t ;;::: ; :::i'::"il::":;:.;T:li:l"ary Desisn Da,a
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t Drawing - Drainage Study Sheet No. I of 1.
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The site o
developmen
cated on twith Vaila slope ofoff fl owsnorth s'i de
There are
wou I d tend
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GENERAL
Sky Lion
ment i n
Towns hi p
i s shown
subdivision isVail, Colorado i
5 South, Range
on the vicinity
The current plan for thjs site consjsts of one large building
located at the southwest corner of the si te. The remainder of
the site wil'l remain undeveloped in its present condition.
The total area of the site is approxinately 4.6 acres and theoff-site tributary area is approximate'l y .|3.3 acres. The
owner of this site is Mountain Properties, Ltd. of Chicago,Illinois.
'located i n the Li on's Ri
n the southeast quarter
Bl West of the 6th P.M.fidp, Figure 1.
dge Deve'l op-of Section l,
The si te
The objective of this study is to de'l ineate any possible
drainage prob'l ems and prov'ide the necessary facilities to
meet the requirements of Eagle County and to eliminate anyfuture drai nage probl ems .
AREA DESCR I PTI ON
f thi s deve'l opment i s I ocated i n the Li on 's Ri dget near Vai'l , Co'l orado, and more specif ica'l 1y is 1o-
he north side of Sandstone Drive at the intersecti on
View Drive. The site is quite steeply s'loped with
approximately 2:'l (horizontal-vertical). All run-
fronr the north to the south and then east alonq theof Sandstone Dri ve.All the runoff is sheet flow.
no defi ned draj nage courses on the si te whi chto channel ize any runoff.
III CRITERIA
The cri teria used i n thi s drai nthe requirements of Eagle Countthe drainage facilities be constect the devel opment on the si tflood, specifica'l1y the 100-yea
were then used i n conj uncti on w
contained in the Denver Reg'i ona
Urban Storm Drainaqe Cri teria M
age study is consi stent wi thy. These requirements are that
tructed such that they wi 11 pro-e from damage during a majorr storm. These reeuirementsith the desiqn informationI Counci I of-Governments'
an ua I .
To devel op the runoff i nformati on i n thi s study i t was
necessary to generate a rainfall intensity-duration curve forthis particular area. Since rainfall information in thispart of the State is limited, i t uras necessary to developthe rainfall curves from three seDarate sources of information
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Drainage Study -
August 15, 1975
Pa ge Two
Skv Lion Subdivision
Information derived from each of the sources was pl otted
and analyzed. The relative accuracy in app'l 'icabi lity of
each publication was evaluated. Based on the analysis and
evaluation the following procedure was adopted.
These sources of information are as follows:
" Preci pi tati on - Frequency Maps for Col orado, " prepared
by Specia'l Studies Branch,0ffice of Hydrology, Environ-
mental Science and Services Administration-Weather
Bureau for Engineering Division, Soii Conservation Ser-
v'i ce, U. S. Department of Agriculture, 0ctober, 1967.
"Rainfall Frequency Atlas of the Ll nited States," Techni-
ca'l Paper No.40, prepared by David M. Herschfe'l d,
Cooperative Study Section, Hydrologic Services D'ivision,
U. S. Department of Commerce, l,leather Bureau for the
Engineering Divisjon, Soil Conservation Service, Mdy,'loAl
"Urban Storm Drainage Criteria Manual ", Denver Regional
Counci'l of Governments, March, .l969.
Use the basic 6 hour and 24 hour precipitation
values obtained from the "Precipitation-Frequency
ttlaps f or Col orado", dated 0ctober , 1967 .
Extend the prec'l pitation values obtained from
"Precipitat'i on-Frequency Maps for Colorado" by useof the rainfal'l -depth-duration diagram contained
i n Techni cal Paper 40.
Use the depth-duration frequency graphs in the
Urban Storm Drai nage Cri teri a Manual to determi neprecipitation amounts of very short duration storms.
The design rainfa'l I values obtained by this method are shownin Figure 2, Rainfal l-Depth-Duration-Frequency graph and in
Figure 3, Rainfall Intensity-Duration Curve.
For the drainage systems and runoff in this study, the Rationa'l
Formul a was used as the basi n i s rather sma'l I . The rrCrl
factor used for the hi stori c conditi on was .30 and the "C"factor used for the developed portions of the site was .72.
A natura'l rtCrr factor of .3 was used as the site is very steeply
s I oped. Al so an antecedent moi sture condi ti on factor of I .25
was applied to the .|00-year storm.
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Drainage Study -August .l5, .|975
Pa ge Three
I V. CALCULATION
Sky Lion Subdivjsion
Flows for the 100-year storm for this reportusing the Rational Formula both in the dbve'lcondition. These ca'l cu'l ations are shown inDrainage System Preliminary Design Data.
were ca'l cu I ated
oped and historicFigure 4, Storm
PROPOSED DRAINAGE SYSTEM
The draing.gq. system for this site is designed to prevent damageto-the building during the 100-year or smaller storm. Thiswill be accompljshed by.constructing a smal'l "vee" shapedswale uphill (northwest) of the buiTding which 'wi'l'l interceptthe runoff and divert it away from the building. The exactsize and location is shown on the attached drainage studysheet I of l.
To protect the entry to the site and sandstone Drive, it wil'lbe necessary to place an l8-inch CMp under the entry and im-prove the existing drainage ditch along Sandstone Diive.The sizes and location of the ditch along sandstone Driveand the entry culvert are shown on the attached drainaqestudy draw'ing.
S UMMA RY
4.dluinusg study has been completed for the Sky Lion sub-division located near vail, colorado. Fo'r rowiirq the recommen-dations of thi s report shoul d prevent any possi 5l e damage tothe site due to f'l ooding in the future. -
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GINGERY ASSOCIATES, INC.
Prepared By
Revi ewed By
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VII. Figures
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