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CASELOAD SUMMARY SHEET
City of Aspen
DATE RECEIVED:
DATE COMPLETE:
9//5/01
PROJECT NAME :JdtJ-e... Nd)
Project Address:
APPLICANT:
Applicant Address:
REPRESENTATIVE:
Representative Address/Phone:
TYPE OF APPLICATION:
PAID: 8 NO AMOUNT:
1 STEP APPLICATION:
(///rJ/VV
P&Z MEETING DATE:
PUBLIC HEARING: YES NO
DATE REFERRED:
INITIALS:
2 STEP APPLICATION:
CC
MEETING DATE:
PUBLIC HEARING: YES NO
DATE REFERRED:
INITIALS:
REFERRALS :
City Attorney
City Engineer
Housing Dir.
Aspen Water
City Electric
Envir. Hlth.
Aspen Consolo
S.D.
Mtn. Bell
Parks Dept.
Holy Cross
Fire Marshall
Fire Chief
Roaring Fork
Transit
School District
Rocky Mtn Nat Gas
State Hwy Dept(GW)
State Hwy Dept(GJ)
Bldg:Zon/Inspect
Roaring Fork
Energy Center
Other
FINAL ROUTING:
DATE ROUTED:
INITIAL:
City Atty
City Engineer
Bldg. Dept.
Other:
FILE STATUS AND LOCATION:
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'mBLEOFCON'l'ENTS
CONCWSIONS
1
1..'0 RiU'OSE IlND SCOPE OF STUDY
l"i<3. 1.0-1 - IDeation Map
2.6 moPOSEODEVELOPMENT
3.0 S.I'l'E COlIIDITIONS
2
3
5
7
8
8
10
4..0 SlJBSURFACE a:>NDITlOOS
4.1 Subsoils
4.2 Groundwater
s.n OOIIDlm FOUNDAT!Gl CONSIDERATIONS
11
f).O SITE GAADffiS
6.1 Proposed GJ:adirg
6.2 Stability Oonsiderations
6.3 On-Site Surface O(ainage
6.4 Off-Site Surface Drainage
12
12
12
14
14
7.0~
7.1 Groundwater Reg ime
7.2 Potential Impacts
7.3 Mitigation Ooncepts
16
16
17
17
8.0 SOIL COOROSIVIT.l
19
9.0 ADDITIONAL srooIES
10.0 LIMI'l'MIONS
20
21
APPENDIX A - FIEID EXPUItATIOO AND 1Al3ORATORY TESTI~
FIGS. A-l AND A-2 - roGS OF EXPLORATORY BORI~S
FIG. . A-3 - LF.GI::NI) AND ~
FIGS.A-4 THROOGl A-9 - GRADATICN TE.crr RESULTS
TABLE A-I - SlMMARY OF LABORATORY '1'ES'l' RESULTS
PJ:ATB I - SITE PLAN AND pROFILE SHcw.rOO LOCA'fIONS OF EXPLORATORY BORI~S
AND mOl?OSEO GAADI~
Cben& Associates
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CONCLUSIONS
1.
Subsoils:
'!he subsoil!;; encountereO in Holes 1 through 3 on the slope
consist of the earthflow deposits ...tlich are comprised of unstratified,
angular to subangular cobbles, gravels am occasional boulders in a
clayey sand to sarrly clay matrix. '!he subsoils in Holes 4. through 6 on
the north portion of the site' consist of eX'istilB fill and/or natural
sandy clay to depths~tlfo'\:en 10 and 15 .feet overlying relatively clean
!
. granular glaciofluvial depo$its.
Nl.lClerous cobbles am boulders Iooere
encountered to a depth of about '30 feet.
2. Foundation Considerations: '!he den$e to very dense granular soilS under-
lying the proposed hotel location are suitable for support of spread
footing foundations at relatively high allowable bearing pressure$' We
anticipate an allowable soil bearing pressure on the order of 6,000 psf.
3. Site Grading: '!he major factors which will influence slop:! stability
with respect to the proposed 9radilB are potential shallow groundwater
and fill placement on the. slopes.
'!he extent am depth of the fill
placed on the slope should be limited.
Addi t ionalslopestability
analysis will be conducted after further field data are gathered in the
Spring of .1986,
4.
Groundwater:
Groundwater mitigation measures consisting of subsurface
drains in the slope and .underdrain systerrs for the buildin;J may be re-
quired. '!hese relatively shallow mitigation mea.,ures should not affect
performance of the existing ~ll near the north side of the site.
Chen & Associates
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1.0 PURPOSE AND SCOPE OF SWDY
'!his report presents interim results of Fhase II of a preliminary geo-
technical study for the Little Nell Base D:veloprent, Aspen, (blorado. 1he
site vicinity is shown on Fig. 1.0-1 and the project site is shown on Plate r.
1he. study was conducted for the purpose of developing preliminary foundation
reccmnendations, evaluating impacts associated with proposed site grading and
evaluating potential impacts of site ,developnent on fxisting groundwater con-
ditions. ']he study is being ,conducted in general acqordance with our proposal
to Aspen Skiing Company, dated Clctoi::ler 22,198.5. We have completed Fhase I of
the study, a preliminary engineering geologic investigation based on site re--
connaissance, as reported under our Job No. 1 990 85 on Noverrber 4, 198.5.
,
'!he Fhase II field exploration program, consisting of exploratory borings
completed as groundwater monitoring wells, was conducted to -obtain infornation
on subsurface conditions. Material samples obtained during the fieldexplora-
tion progran were tested in the laboratory to determine .the c1assifia'ltion and
index properties of the on-site soil. 'Ihree of the borings were . located on
the upper portion of the site in the area of, proposed slope excavation to
evaluate soil and groundwater conditions as they will relate to excavation.
']he remaining three borings were located on the low lying north portion of the
site to explore subsurface co,nditions at the location of the proposed hotel
and to explote groundwater conditions in the area of the existing well and the
area of a suspected spring near the west site boundary. The results of the
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1'112285
LOCATION MAP
f'1c. 1.0-1
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field exploration and laboratory testing were evaluated to develop preliminary
recOmmendations for building foundations, site grading and groundwater mitiga-
tion. ,This preliminary study will not be complete until groundwater m:mitor-
iog is completed in the spring of 1986. N:. that time, the analysis and report
will be canpleted. The results of the field exploration and laboratory
testing are presented in Appendix A.
This report has been prepared to sunmarize the data obtained during this
study and to present preliminary conclusions and recommendations based on the
proposed construction and the subsurface conditions encountered. A discussion
of geotechnical engineering considerations related to development of the pro-
posed project are included in this report.
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2.0 mOPOSED DEVELOPMENT
Conceptual plans indicate the proposed base developnent will include a
96-unit hotel near the northeast corner of the property. A pedestrian/
carunercial area is planned at approximately the existing grade ofDJrant
Avenue. Mud1 of the proposed coomercial area will be earth sheltered, con-
structed below grade ,into the toe of the slope. N=w ski base facilities,
including a higher capacity lift or gondola, are planned just upslope of the
hotel and coomercial facilities.
ve understand the proposed hotel will have three levels above grade and
tw::> parking levels below grade. SinCe the developrent is in the conceptual
stage; the proposed type of construction and anticipated structural loadings
are unknown at this time. l'e assurre the structures will be of reinforced
concrete or reinforced concrete and steel frame construction. Based on our
understanding of the proposed structure, \..e anticipate maximun colum loads on
the order of 500 to 700 kips.
To accarmodate the planned base facilities and improve the grade of the
ski slope, extensive site grading of the lower mountain slope is planned. 'lhe
generally convex portion of the slope on the project site will be excavated to
provide a more uniform slope as sho\\n on Plate 1. Excavation depths on the
slope range to about 25 feet. Subsequent to our field investigation, we were
provided with a revised grading plan which indicated large quantities of fill
will be placed upslope of the project site. Fill depths up to about 25 feet
are now proposed in that area.
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If the design varies fran the project description presented above, the
recomnendations presented in this report should be reevaluated. Wlen a speci-
fic project configuration is developed, a geotechnical review of the proposed
project should be conducted and additional exploration and analysis as re-
quired performed.
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3.0 SITE CONDITIONS
':the site is located south of D.Jrant Avenue betw=en Spring street and
Galena Street near the base of Aspen Mountain. 'tl1e site boundary is indicated
on Plate I. There are several existing structures on the nortliern part of the
site including the Aspen Mountain Ski Company offices, rraintenance shop, lift
ticket office, and the Little Nell Restaurant and associated businesses. An
existing ski lift is located on the eastern portion of the site. 9:he North of
Nell ccmnercial and condominium building is located near the northwest corner
of the site. An existing well am pLlClp house are located just north of the
northern property boundary. Existing' condominium and residential structures
are located near the east and w=st boundaries of the site. The ski trails on
Aspen Mountain are located south and upslope of the site.
Approxirrately the northern one-<juarter of the site is relatively flat.
'lhe southern three-quarters of the site on the lower slopes of Aspen Mountain
slope down from south to north. 9:he .existing slope on the project site ranges
from about 25% to 33%. Slopes less than 20% are present immediately south of
the site with much steeper slopes further south up the mountain. 9:he center
porton of the site is the toe of a large lobate earthflow. 9:he surficial geo-
logy on-site and upsLope of the site is discussed in our Phase I (preliminary
engineering geologic investigation) report.
Chen & Associlltes
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4.0 SUBSURFACE (X)NDITIONS
4.1 Subsoils
Subsurface exploration was conducted as described in Appendix A. Holes 1
through 3 were drilled on the upper portion of the site in the large lobate
earthflow deposit. Holes 4, 5 and 6, drilled in the relatively flat northern
one-quarter of the site, penetrated a layer of existirg fill and colluvilJ1\
overlyirg granular glaciofluvial deposits.
'!he earthflow deposit encountered in the borirgs consists of unstrati-
fied, angular to subangular cobbles,' gravels am occasional boulders in a
clayey sand to sandy clay matrix. Iayers of sandy clay and clayey to very
clayey sand were encountered in Holes 2 and 3. Penetration resistance values
indicate the granular materials are generally rredium dense to very dense.
However, the clayey sam at the bottcm of Hole 2 was loose. Very stiff sandy
clay was encountered in the lower 7 1/2 feet of Hole 3. We have conducted
previous exploration in the vicinity and upslope of the site W::iich indicates
that m::>st of the gravel, cobbles and boulders are aplite porphyry with minor
amounts of shale and limestone W::iidl were probably derived from the Beldon
Formation, and minor anounts of sandstone.
'!he subsoils encountered in Holes 4, 5 and 6 consist of 11 to 15 feet of
existing fill and/or natural sandy clay colluvillU overlying granular glacio-
fluvial deposits. '!he existing fill rraterials consist of varying mixtures of
sand and clay with cinders. Our observations and the penetration resistance
values imicate the existing fill materials are erratic in canposition and
degree of compaction. We did not determine the vertical and lateral extent of
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fill on the site as a result of this study. However, fill was encountered in
two of the three borings drilled in the level area of the site.
Sarrly clay colluvium \\as encountered just above the granular subsoils in
Holes 4 and 6. Based on penetration resistance values, the clay is soft to
medium consistency.
Granular subsoils were encountered in Holes 4, 5 and 6 at depths between
11 and 15 feet. '!hose materials generally consist of slightly silty to silty,
sandy gravel with cobbles and boulders. Lenses .of slightly silty to silty
sand were encountered at depth. Extremely difficult drilling conditions in-
dicating relatively large quantities of cobbles and boulders are present at
about 15 to 30 feet in depth. Granular materials with smaller grain sizes and
less difficult drilling conditions were generally encountered below that
depth. '!he granular materials in Holes 4, 5 and 6 were derived principally
from relatively hard granitic rock away from the imnediate vicinity of the
site. '!he rock fragments are generally subrounded as opposed to the angular
to subangular rock fragments in the earthflow deposit.
Penetration resistance values indicate most of the glaciofluvial deposits
are very dense'. However, samples of mediLm dense to dense sand were obtained
from Holes 4 and 5 at a depth of about 40 feet. '!he results of grain size
analyses corrlucted on samples of the granular subsoils from the borings are
presented on Figs. A-4 through A-g in APl?€ndix A.
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4.2 Groundwater
Groundwater monitoring \<.Blls ~re installed in all of the exploratory
borings, as described in Appendix A. fue water levels measured in the
borings are shown the IDgs of Exploratory Borings, Figs. A-1 and A-2 in
Appendix A.
fue water levels measured in fbles 2 and 3 range from 29 1/2 to
32 1/2 feet. Water was not encountered in fble 1 to a depth of 26 feet.
Water was not encountered in fbles 4 and 6 to depths of about 50 feet and 26
feet, respectively. Cbservation wells were installed in those tlo.O holes to
depths 46.5 feet and 24 feet, respectively. ']he water level infble 5 stabi-
lized at a depth of about 40 feet. A water level of about 34 feet has been
reported in the \<.Bll just north of fble 5. ']he corresponding elevation of
that water level is within 2 to 3 feet of the water level elevation measured
in fble 5. A water level profile was estimated based on the water level
readings in the borings as sho"l"l on Plate 1.
Chen &Associates
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5.0 BUIWINS FOUNDI\TION CONSIDERATIONS
'!he dense to very dense granular subsoils underlying the proposed hotel
site are suitable for support of sprea:! footing foundations at relatively high
allowable bearing pressures. As previously noted, \>e assune the ll'aXimum anti-
cipated colunn loads will be in the range of 500 to 700 kips or less. Based
on our understanding of the proposed construction and the preliminary explora-
tion, we anticipate spread footings placed on the natural undisturbed granular
soils rray be designed for an allowable soil bearing pressure on the order of
6,000 psf. Those materials ~re encountered at a depth of about 11 feet in
Hole 4. Existing fill rraterials and clay will have to be removed before
placement of foundations. Ho~ver, the proposed two-level basement v,ould
indicate excavation beyond the expected depth of fill and clay.
Once specific structural types and locations have been determined, a
design level soil and foundation study should be conducted to determine
foundation design criteria.
Chen & Associates
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6.0 SITE QW)IN::;
6.1 Proposed Grading
'!he grading proposed on and above the site is Sllmlarized by the contours
arrl profile shown on Plate 1. At the ti.Jre of our field exploration, v.e under-
stood the planned grading w::>uld consist only of excavation. W= now tmderstarrl
it is proposed to place the excavated material upslo~ above the excavated
area in the shaded area shown on Plate 1. '!he intent of the fill placement is
to dispose of the excavated material arrl to improve the configuration of the
ski slope. '!he preliminary grading plan indicates cut' depths up to about
25 feet arrl fill depths up to about 25 feet.
6.2 Stability COnsiderations
'!he stability of a slope de~nds on the engineering properties of the
subsurface materials, the georretry of am interaction betv.een the various sub-
surface llI1its, arrl the groundwater conditions. A limit equilibriun stability
analysis calculates a factor of safety, which is the ratio of forces resisting
slope rrovement to the forces tending to cause slope movement along an assuned
failure surface.
To corrluct a stability analysis, it is necessary to realistically rrodel
all of the above factors. For the proposed grading, it is necessary to con-
sider the effects of changing all of those factors both above arrl below the
graded area. In general terms, excavation into the toe of a slope can reduce
the forces resisting slo~ rrovernent and plaCEment of material on the top of
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the slope can increase the forces tending to cause slope movement. fuerefore,
both grading actions are destabilizing influences. A destabilizing influence
is one Iotlich reduces the factor of safety, but not necessarily to an unac-
ceptable level.
/', detailed stability analysis W3.S not proposed or corrlucted as a part of
this preliminary study. 'Ihe grading proposed at the time Io.e initiated our
study w:>uld have essentially resulted in unloading the existing slope by re-
moval of the 10lo.er bulged portion of the slope. '!hat grading \\Quld not be a
major destabilizing influence; the lTBjor concern W3.S to identify p:>tential
shallow groundwater levels or seepage conditions. As previously noted, Io.e now
understand fill placement on the slope above the excavation is planned. .&1r-
charging the excavated slope will have a destabilizing influence.
Holes 1 through 3 Io.ere primarily intended to explore the lTBterials which
will be excavated and determine groundwater levels. Water levels 32 1/2 and
29 1/2 feet below the proposed grade Io.ere encountered Holes 2 and 3, respec-
tively. l-e expect a rise in those water levels duril19 the spring and early
sunmer period. fue W3.ter levels in the exploratory borings will be checked
during that period. A groundwater level near the final ground surface planned
and seepage through the cut face .will have destabilizing influences on the
slope. After the data have been gathered, the influence of the higher ground-
water levels will be studied.
Additional study including detailed stability analyses will be required
to evaluate the impact of the proposed fLU on the slope. Although Io.e expect
sorre fill placement will be p:>ssible, """ do not have enough information at
this time to comnent on the degree of destabilization Iotlich will be induced by
the prop:>sed fill. Some of the prop:>sed grades are significantly steeper than
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the existing grades near the east side of the proposed fill. For planning
purposes, \Ie suggest the extent and depth of the fill be limited.
Prior to further evaluation of the impacts the planned grading will have
on slop" stability, water level information must be obtained during spring
runoff. Additional field exploration required to analyze the effects of the
proposed fill placerrent should be done at that time.
The present water level in Hole 3 indicates groundwater could impact the
toe of the slope. Groundwater mitigation concepts are discussed in 8ec-
tion 7.3 of this report.
6.3 On-Site Surface Drainage
Good surface drainage should be provided to protect slop" faces from sur-
face runoff. All slop" faces should be protected against erosion by revegeta-
tion or other rcethods. In addition, positive surface drainage should be
provided away from buildings to prevent surface water infiltration into
backfill.
6.4 Off-Site Surface Drainage
As stated in our previous preliminary engineer in:! geologic investigation
report, potential off-site impacts to the proposed developrent include the
potential for flood and debris flow events entering the site. The existing
Copper/Spar Gulch and Vallejo Gulch drainages discharge near the top of the
Little Nell earthflow. As previously reccmnended, the potential flood/debris
flON risk should be studied by a surface water hydrologist and evaluated in a
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canprehensive water/flood routing study. 'Ihe study should consider the im-
pacts associated with the proposed grading.
Chen & Associates
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7.0 GROUNIWATER
7.1 Ground\oater Regime
A projection of the groundwater levels in the holes along a 1.0IBituHnal
section through the site is shoW"! on Pl.ate I. Our experience in ,the area
indicates \oater levels on Aspen /obuntain can be quite shallow and with sig-
nificant fluctuation due to seasonal, runoff. fue lower p"rtion of the site
and the well near the north site boundary are underlain by relatively clean
;
glaciofluvial dep"sits. fue well taps an aquifer of relatively high perme-
ability and large areal extent. 'Ihe' earthflow deposit upslope has consider-
able fines content and the soils are probably much less perrreable than the
glaciofluvial deposits.
']he groundwater systan in the earthflow deposit
,
probably contributes little recharge to the glaciofluvial aquifer comr:ared
with total available recharge. ~asonal fluctuations in. \oater levels within
the earthflow deposit should have little impact on the \oater levels in the
aquifer tapped by the well.
We understand seepage has been reported in the vicinity of Hole 6 on the
northwest portion of the site.
We also understand that seepage may have
resulted fran :a broken waterline upslope. Based on the groundwater levels in
Holes 4 and 5 and the absence of .\oater in Hole 6, we do not believe the
rep"rted seepage resulted fran a high groundwater level.
It is p"ssible
surface runoff or water fran a broken waterline could nanifest itself as
seepage at that location due to the relatively low penneability expected of
the shallow clay soils.
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7 . 2 FOtential Impacts
The primary impact groundwater will have on the proposed project is the
potential effect on stability of the regraded hill slope above the building
sites. Based on the present water levels, there appears to be a potential for
shallow water conditions or seepage to occur near the toe of the proposed
cut. Water levels will be measured in the rronitorlng \\Blls throughout the
spring and early sumner of 1986 to better evaluate the potential groundwater
impact on grading.
Another potential impact is the groundwater mitigation rreasures on the
slope to effect the performance of the el(isting ~ll. In our opinion, the
relatively shallow mitigation measures which may be required on the slope will
not significantly impact the well production.
7.3 Mitigation Concepts
It is likely subsurface drainage measures will be required to prevent
high water levels an:'! seepage in the proposed cut. Although subsurface drain-
age recomnendations will depend on additional exploration, monitoring and
analysis, v.e suspect transverse trench drains on the order of 10 to 15 feet
deep on the lower portions of the cut may be necessary.
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Below ground construction on the site should be protected by underdrain
systems. Although the present water level in Hole 4 is \-.ell below the
proposed lo~r floor level, our experience in rrountain areas indicates <>et
basement conditions ,can result from snow melt infiltrating the subsoils around
structures.
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8.0 SOIL CORROSIVITY
We understand there have been problems in the area with corrosion of
buried metal pipes. We .reasured _ter soluble sulfate cont.ents an:l pH of four
samples of the naterials from the earthflow deposit to determine ...nether those
factors \'.Quld contribute to corrosion of buried metal. '!he _ter soluble
sulfate contents range from 0.001 to 0.007 and, pH ranges from 7.0 to 7.4 as
shown in '!able A-1. '!he water soluble sulfate contents are low an:l the pH's
are neutral to slightly basic. Therefore, those factors will not contribute
to corrosion of buried metal.
'ltle electrical resistivity of a soil will indicate it's corrosivity to
buried rretal. Sorre of the clayey materials in the earthflow deposits are
likely to have relatively low resistivities, especially at high moisture
contents. We do not expect the granular glaciofluvial soils at the north end
of the site to have resistivities low enough to be of concem.If buried
metal pipes are to be embedded in the earthflow deposits, or in the existing
clay or fill materials near the north end of the' site, soil resistivity sur-
veys should be conducted in the field at the locations of the proposed
pipes.
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9.0 ADDITIONAL STUDIES
'!he recarmendations presented in this report are preliminary in nature.
I\dditional studies will be required to address buildin:J foundations am site
gradin:J. A design level foundation stLXly should be coooucted in the proposed
hotel area once plans are more definite. A thorough study of the conditions
effecting the stability of the slope should be conducted if any fHl placement
is proposed on the slope. 1he studies cannot be completed without high
groundwater level information obtained during sprin:J runoff. klditional
studies are also warranted to define the surf.ace \O.6ter hydrology of the site
. am evaluate the flood and debris flow' risk.
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10.0 LIMI'mTIONS
'Ihis report has been prepared in accordance with generally accepted
geotechnical engineerin;J practices in this area for use by the client for
preliminary design and planning purposes. 'Ihe conclusions and recomnendations
submitted in t:his report are based on the data obtained fran the widely spaced
exploratory borings drilled at the locations shown on Plate I. ldditional
studies have been recoourended to further evaluate site geotechnical condi-
tions.
If you have any questions or if ..e can be of further assistance,
please contact us.
CHEN & ASSOCIATES, INC.
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Afb~
-By~~~'
ineering C~ologist
;.----
Reviewed By'ib.<>~
Harold HoI ing rth, Jr., P.E.
AC/eac
cc: D:sign w:>rkshop, Inc.
Attention: Mr. Bill Kane
Chen &Associatcs
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APPENDIX A
FIELD EXPLORATIO'l AND IABORA'lDRY TgSTIN:; PROGRAMS
Chen & Associates
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Field Exploration Progran
The field exploration program was conducted from November 5 through 8 am
11, 1985. Six exploratory borings \iere drilled at the loeations sho\oKl on
plate 1. IDeations and elevations of the borings \iere surveyed by the
client's surveyor subsequent to drilling and given to us prior to preparing
this report.
The borings I<.ere advanced through the overburden soils with 4-inch dia-
rreter continuous flight augers. ']he borings \iere logged by a representative
of Olen & Associates, Inc.
Samples of the subsurface 'Taterials \iere taken with a 2-inch and a
1 3/8-inch I.D. spoon sampler. ']he samplers ~re driven into the various
strata with blows from a 140-pound hammer falling 30 inches. This test is the
standard penetration test described by AS'IM Method D-1586 when the 1 3/8-inch
1.D. sanpler is used. R:netration resistance values, when properly evaluated,
indieate the relative density or consistency of the soils. Cepths at which
the samples ~re taken and the penetration resistance values are shown on the
Logs of Exploratory Borings, Figs. A-1 and A-2.
Groundwater monitoring ~lls I'oere installed in all of the borings by
placing slotted plastic easing wrapped in filter fabric to near the bottoms of
the holes. Granular oockfill was placed around the casings. Steel surface
casings with locking caps l.ere embedded in concrete at the tops of the '-'?lls
for protection. The tops of the casings ~re placed flush with the ground
surface.
Measurements of the water level l.ere made in the borings by lowering a
\ieighted plumbline into the monitoring wells tlo.U days to seventeen days
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subsequent to drilling. '[he depths of the water levels rreasured and the
number of days subsequent to drilling are shown on the logs of Exploratory
Borings.
laboratory 'lesting Progran
Samples obtained fron the exploratory borings \\ere examined and visually
classified in the laboratory by the project engineer and project geologist.
'!he laboratory testing conducted incllXled standard property tests, such as
natural moisture content (AS'lM D-2216), dry unit \\eight, grain size analysis
(AS1M 0-422) and liquid and plastic limits (AS'IM 0-4318). '!he percentage of
water soluble sulfates in general accordance with "Standard l>Ethods for the
Examination of vater and Wastewater, 15th ed.," and the pH v.ere detennined for
selected samples.
Results of the laboratory testing program are shown on Figs. A-4
through A-9 and in the attached SlllTlllary of Iaboratory 'lest Results, '!able A-
I. 'Ihe laboratory testing was conducted in general accordance with applicable
AS'IM standards.
Chen & Associates
10 24/12 22112
WC=13.9
00=98.7
.19/12 +4=19
WC=9.3 -200=46
15 +4=78 LL=34 15
-200=6 PI=16 32/12
LL=27 1.'55=0.007
PI=7 pH=7.2
I- WS5=().OOl-- 16/12 I-
"-' '"
"-' pH=7.0 WC=12.0 "-'
... ....
20 28/12 24/12 +4=45 20
:I: WC=5.8 -200=21 :I:
I- +4=65 L,L=28 I-
0. 0.
"-' -200=10 - "-'
'" P 1=11 '"
-- 1.'55=0.003
pH=7.4
25 36/12 28/6 6 7/12 25
-=-
.
"
Hole I Hole 2
E I . =8041 . I ' E I . =80 12.6 '
Proposed G!'3de (Typical)
o
32112
5
30
35
40
I 1122 35 Chen & Associates
25/12
38/12
8/12
WC=10.9
+4=28
-200=31
LL=29
PI=12
Hole 3
EI.=7973.6'
17
o
5
40/12
30
........
-
25/12
WC=16.3
+4=5
-200=73
LL=35
PI=16
4/12
WC=20.0
-200=68
LL=29
PI=8
35
40
LOGS OF EXPLORATORY BORINGS
Fl., A-I
N
N
'"
'" '
ri
:r
~
=
l(c
>
CIl
CIl
Cl
/')
-.
~
-
~
CIl
m
r-
m
<
".
-<
o
Z
."
m
m
-<
r-
o
'"
VI
o
."
m
X
."
r-
o
'"
".
-<
o
'"
-<
'"
o
'"
Z
'"
VI
:!l
'!"
".
,
N
Hole 4
E1.=7940.0'
7940
7935
52/12
Hole 5
EI.=7938.4'
13/12
Hole 6
EI.=7938.0'
7940
7935
7930 4/12 7930
15/12 7/12
WC=21.2
-200=78
LL=34
7925 53/12 P 1=1 I 7925
wSS=0.003
40/6 pH=7.4
7920 ~
Est imat~~~J
Lower Floor
Level
7915
7910
7905
7900
7895
7890
7885
-56/6
WC=I .4
+4=54
-200=8
50/6
53/12
~:o
'0
,.'0'0
ll:~"
O. ,
'.
.>.Q
:~
.;,...
42/12
wc=8.0
50/6 13.16
+4=8 -=
-200=26 3
NP
68/6
--
40/3
120/8
WC=4.3
+4=40
-200=13
75/12
WC=4.3
+4=16
-200=8
19/12
wc=8.6
+4=1
-200=7
110/8
. 75/8
t
7920
7915
7910
7905
7900
71>95
7890
7885
,.., ~
__I
"'
m
r-
m
<
~
o
z
."
m
m
-<
N
N
Cl:>
'"
~
=-
~
=
~
>
C"Il
C"Il
~
"
-.
~
it
C"Il
r-
'"
C")
'"
:z
'"
:>
:z
'"
:z
o
....
'"
V>
~
".
,
W
LEGEND:
24/12
m
ro
.._I
.'
j
rn
Topsoil, sand, gravelly, silty, clayey, moist, dark brown.
~
Co'ushed rock fi 1 I.
~
Fill, varing percentages of sand and gravel, cLayey to silty, occasl'onal sandy clay, generally not
compact, moist, brown to black, cinders.
u
Clay (CLl, low to medium plasticity. sandy, silty, medium to very .stiff, moist to very moist, yellowish
broIVn to brolVn, lenses of clayey to si lty sand, scattered gravel and, cobble.
~
W
Sand (SP-SM). fine to coarse grained IVith gravel. sl ightly silty, medium dense to very dense. 1 ight
moist to IVet. light brolVn.
t].
~and (SC), fine to coarse grained IVith gravel, clayey to very clayey, loose to very dense, I ight moist
to wet, mixed browns.
~'.
.'
.
Sand (SM). fine to coarse grained IVith gravel, silty, dense to very dense, light moist,
light brolVn.
~
Gravel (GP-GCl. fine to coarse grained IVith cobbles and boulders, slightly clayey sand matrix, medium
dense to very dense, moist to wet. mix.ed browns.
PJ?l
[ill
Gravel (GC), fine to coarSe grained IVithcobbles and boulders, clayey sand to sandy clay matrix.
medium dense to very dense, moist to wet, mixed browns.
f??,1
~
Gravel (GP-GM). fine to coarse grained IVlth cobbles and boulders, sandy. sl ightly silty to clean, very
dense, light moist to IVet, light brown.
p
~
Drive sample, 2-lnch 1.0. California I iner sample.
Drive sample, Standard Penetration Test,
3/8-inch 1.0. spl I t spoon sample.
Drive sample blow count. IndIcates that 24 b.lolVs of a 140-pound hammer falling 30 Inches were
required to drive the Cal ifornia or SPT sampler 12 inches.
Indicates PVC pipe installed In hole to depth shown.
6
Depth to IVater level and' number of days after drl Il.lng measurement IVas made..
--- Depth at IVhich test hole caved.
~
Pract ical rig refusal.
NOTES:
1. Exploratory borings IVere dril led on November 5 through 8 and 11, 1985 with a 4-tnch diameter continuous
flight auger.
2. Locations of borings IVere surveyed by the client's surveyor..
3, Elevations of borings IVere.. surveyed by the cl lent's surveyor.
4. The lines betIVeen materials shoIVn on the boring logs repre.sent the approximate boundaries between
nlaterial types and the transi t ions may be gradual,
5. W'at~r l~vel reduing:> l>r.()wn un LhE::!logs w~re rtlC:loe at the lillie, andundercol.oilions inclicdted.
FJuctuations _Ln~the water level may occu'rwlth time.,
6. Laboratory Test Results:
WC=Water Content (%);
DD=Dry Densi ty (pcf);
+4=Percentage retained on No.4 Sieve;
-200=Percentage passing No. 200 Sieve;
LL=Liquid Limit (%);,
PI=Plasticity Index (%Y:
NP=Non-plastic;
WSS=Water Soluble Sui fates (%);
pH=So i I Ac i d i ty.
CA-2.19'"
chen and associates, inc.
HYOROMETE:R' ANALYSIS
TIME. READINGS
SIEVE ANALYStS
uS ST .wOAOO SERIES CLEAR SQUARE PENlN
'<0
24 HR. 1 HR
,
100
SMJN 15MlN .6Q ~lIN19 MIN 4 MIN IMIN ."'" '100 " 'SO "40 ~30 ',16 'R ., .... I.... "..,.. ,.. 5~6 . R'
.0
,
0
1
.002 .005 .OO!l .019 .031 .074 .149' "" .590 1.19 2.38 4.76 9.52 19.1 38.1, 76.2 >21 2 ,
I
90
80
~.6Q
;;;
.,
<
~5O
~
Z
w
~AO
w
~
""
20
'0
o
.0<1
42 2,0
DIAMETER OF PARTICLE IN MILLIMETERS
SAND
FINE ME1)IUM COAASE
052
GRAVEL
FINE COARSE
C08BLES
CLAY TO SIL T
GRAVCL 78
16 ..
SAND
...
SILT AND etA v
...
PLASTICITY INDex 7
6
"
...
LIQUID LIMIT
27
SAMPLE OF S I j gh t lye I ayey
sandy gravel
H61e j at depth 14.5'
FROM
HY'OROMETER ANALYSIS
TIME READINGS
SIEVE ANALYSIS
u.S, STANDARD SERIES CLEAR SOUARE OPENINGS
"0
S.
24HH 7HA.
SM1N M 60MN
"'"
'100
.""
,.
N
.5O
,
"
z
;;;
':I
~
~
z
w
"
~
w
.
, 05 'N I .19MIN,4MI t MIN "0 '" 'S ., . ,. I'"~ S'
.00
90 '0
80 20
1<l ""
'"
50 50
'0 60
'" 10
20 60
'0 90
-
0 ,
''''' 002 00' OO!l 0"' "" o~.. .., 291 590 01' 0'" ". 9!52 "" ", 76.2 121 M
00
CLAY TO SilT
42 20
OIAMETER Or PARTICLE IN MILLIMETERS
SAND
Ml'OlliM
COaBU:S
os,
GflAV€l
fINE COAIlSE
FINe
COARSE
GRAVEL 1 0
SAND 1,1,,,
"
1,6
SIL.T AND Ct.A v
...
L10UIQ LIMIT
31,
..
..
PLAsnCITY INDEX 16
Hole 2 at depth 19.5'
SAMPLE OF Ve I"Y clayey sund
FROM
GRADA TION TEST RESULTS
. A-y
Flg..__
1 1122 85
'..
o
20
30
o
w
'"z
"
~
w
so~
~
z
w
60"
~
w
~
o
80
'"
00
o
w
Z
"
~
w
~
Z
w
<.>
~
w
~
chen and associates, inc.
HYDROMETER ANAL YSIS
TIME READINGS
SIEVE ANAL YSIS
US. ST ANOARO SERIES CLEAR SOUARE OPENING
"0
2' HR. T HR
4
,
00
SUIN 15MIN 60 MINI9 MIN .. MIN 1MIN .,"" .,"" "50 '.0 '30 '" ., ., ". ~." t"i' 3" S'.S' ,-
00
,
0
7
0
0 121 ' 2 ,
, .... DO> .009 .Olg .037 .OT. .149 297 .'00 1.19 '38 4.76 9.52 ,19,1 38.1. 16.2
o
o
80
20
'"
"
zOO
in
~
~
"so
~
z
w
~.w
w
..
o
w
40Z
"
~
w
so<<
~
z
w
ooU
<<
w
..
'"
o
20
80
'"
00
CLAY TOSIL f
."2 2.0
DIAMETER OF PARTICLE 'IN MILLIMETERS
SAND
FINE MEDIUM QARSE
'S>
GRAVEL
FINE COAASE
COBBLES
GRAVEL 65
..
SAND 25 ..
Sit T AND CLAY 10
..
lI0UID LIMIT
..
PLASTICITY INDli:X
..
SAMPLE OF
51 ightly clayey
sandy gravel
FROM
Hole 2 at depth 20'
HYDROMETER ANALYSIS
TIME READINGS
24 HH 1 HR.
.
200
00
SIEVE ANAL VSIS
U,S. STANDARD SEAlES CLEAR SQUARE OPENINGS
"0
.'"
"
z
in
~
~
..
~
z
w
U
<<
w
..
4 MIN,15MIN. 60 MIN, 19 MIN." MIN IMIN ., 'SO '''0 -" 'S ., ..- V.'. "J,H 3' SNS.'
'''''
00
80
'0
40
'" ,
20
'0
0 ,
"'" 00. 00' 009 0.. 037 074 ... 291 .90 "' 38 ... 9~2 ,. , 3'" '" '" .
o
'0
20
30
o
40 'Ii
"
~
w
so<<
~
z
w
oou
<<
w
..
o
80
00
00
CLAY TO SIL f
42 20
DIAMETER OF PARTICLE IN MILLIMETERS
SAND
MEOIUM
IS'
FIN€.
COAIlSE
(;RAV(L
flNE COAI~SE
conAlES
GRAVEL 28
"
SAND 4 I ..
$IL T AND CLAY 31
"
lI0UID LIMIT
29
..
PLASTICITY INDEX 12
"
SAMPLE OF Clayey g'"c1ve II y sund
FOOM
Hole 2 at depth 35.5'
I 1122 85
GRADATION TEST RESULTS
Fig
^"5
l..:,A~'t.~/'d
chen and associates, inc.
HYDROMETER ANAL YSIS
TIME READINGS
SIEVE ANALYSIS
US ST ANOAnD SERIES CLEAR SOUARE OPENINGS
'>0
2. HR. 1 HR
,
'00
,.
SMIN ISMIN 60 MIN. 19 MIN.. MIN lMIN '200 0'00 .500 '.0 '30 .,. ('. " ,.. ","" 1'~" J" 5"6' .
0
1
, 1 I< ." 4.16 .52 1 , I
o
'0
80
20
"
30
o
W
<OZ
"
~
W
5O~
~
z
W
eo"
~
W
"
o
"
Z80
~
"50
~
Z
W
1;1<0
if
20
80
10
..
o
.00'
002
.005.009 0 9
OJ
o 9 ,291 ,590 1.19 2.34
..2 2.0
DIAMETER OF PARTICLE IN MILLIMETERS
SAND
FINE MEDIUM COARSE
9 381.
16.2 121 20000
lSl
Cl.AY TO SIL T
FINE
GRAVEL
COARSE
COBBLES
GRAVEL 45
..
SAND
..
34..
SilT AND CLAY
~1
11"
..
lI0UID LIMIT
28
PLASTICITY INDl:X
SAMPLEOF Clayey sandy gravel
FROM Hole 3 at dePth 20'
HYDROMETER ANALYSIS
TIME READINGS
SIEVE ANALYSIS
U.S. Sf ANDARD SERIES CLEAR SOU ARE OPENINGS
010
2.HH 1HR
,
"
Z
..
~
<
"
~
Z
W
"
~
W
"
, MIN.1SMIIIl 60 MIN. 19 MIN. 4 MIN lMIN '200 .,"" 050 '40 '30 ." ,.8 ., ,.. 10' 11'>' ,.. 5.'6'.
100
,. ,
80
10
'0
30 1
20
10
-
0 ,
"", 002 00' 009 0" 037 01< 1<l19 291 ,,. '" J8 '" 951 ," 361 '" '" ;;
o
o
20
"
o
<oW
Z
"
~
w
5O~
~
Z
W
60<>
~
W
"
o
80
00
""
<lI2 ~ 0
DIAMETER OF PARTICLE IN MILLIMETERS
1~,;>
CLAY TO SIL r
fiNE
SAND
MEDIUM
COAHSE
('.llAVU
r INt' COAH:il
i~ ~
I,., ~
COtllllt~
GRAVEl
5 ...
SAND 22 %
SI!.:. T AND CLAY
LIQUID lIMI T
35
...
PLASTICITY INDEX
SAMPLE OF
Sundy clay
FnOM
Hole ~ ~~t ~ie:)th
,- ,
J~
1122
n.
u~
,
GRAOA TION TEST RESUL TS
Fig ..1\: [~
,,,',
chen and associates, inc.
HYDROMETER ANAL YSI$
TIME READINGS
SIEVE ANAL YSI$
US STANDA'no SERI~S CLEAR SQUARE:. OPENtN
'10
:<'4 HA. 7HR
0'
'00
70
MIN 15MIN 60 MIN 19 MIN 4 MIN 1 MIN '>00 '100 '50 '40'30 0'. I"~ ., ,. l.... "'I''' 3" 5'"6' .
.002 037 .074 " .149 .'90 9.5:<' I
I .005 .009 019 .297 1.19 238 476 19,1 38.1. 76.1 127
o
90
10
80
20
30
30
o
w
",Z
"
~
W
"'~
~
Z
w
600
~
w
..
70
~60
i7>
'"
<
..",
~
Z
w
~40
w
..
20
60
10
'"
o
00
CL.AY TO 51l T
.42 20
DIAMETER OF PARTICLE IN MilLIMETERS
SAND
FINE MEDIUM COARSE
>0000
"2
GRAVEL
FINE COARSE
COBBLES
GRAVEL
54 "
SAND
"
33'"
SILT AND ClA Y
8"
"
LIQUID LIMIT
PLASTICITY INO;:X
SAMPLE OF
S I j gh t Ii s j I t"l
sandy 9ravel
FROM
Hole 4 at de~t~ 1~"3'
HYDROMETER ANALYSIS
TIME READINGS
24HH 7HR
00
SIEVE ANAL VSI$
U.S STANOARD SERIES CLEAR SOUARE OPENINGS
"0
30
"
z
i7>
'"
<
..
~
z
w
o
ffi
"
45 MIN.15MIN. 6OM1N 19 MIN, 4 MIN IMIN '>00 "' .'" .40' 01. " '0 ,.. "'... 1",,' 3" 5"6'"
100 0
90 I
80
70
00
30 7
20
10 90
0 I
.00' 002 00' .009 .019 .037 0" ," 297 '90 1.19 "38 n. '" 19' 381 7.2 m 0
o
20
30
o
"'w
Z
"
~
w
"'~.
~
z
w
60U
ffi
"
o
80
00
CLAY TO 51l T
42'10
DIAMETER OF PARTICLE IN MILLIMETERS
SAND
. M(Olt)M
IS?
FINE
COAHSE
GIlAVf'L
flNI" COAflSt
COBfiLCS
GRAVEL 8 %
L10UID LIMIT NP
SAND
..
66%
$IL T AND CLAY
26 ..
..
PLASflCITV INDEX UP
SAMPLE OF
S I i q;a I 'f ':J r ':-lvcl
sillY sC:lid
I"
,
FIlOM
Ho I (~
o.r
..:(~:) t h i.I'
1122 35
GRADATION TEST RESULTS
Fig.___!'::L
.... ".
CA'2,79
chen and associates, inc.
HYDROMETER ANAL YSIS
TIME READINGS
SIEVE ANAL YSIS
U S.STAN-DAnD SERIES CLEAR SO~ARE OPENIN
'00
24HR. 1HR
..
100
90
M'N 15MIN 60 MIN, 19 MIN 4 MIN 1 MIN '200 "00 "50 "40 "JO '1' ("R ., .... ~," 1'i)M ,.. 5M6' 0'
.
I
7
9.52 I
I 00' .OOS 009 .,. 037 ... ... .297 .S90 1.19 '38 416 19.1 38.1" 16.2 121_2
.
..
20
7.
30
li..
iii
'"
<
~..
~
Z
w
~40
w
~
30
o
w
..Z
.
~
W
..<<
~
Z
w
GO"
<<
w
~
.
20
GO
..
'"
.
.00
00
CLAY TO Sll T
,42 2.0
DIAMETER OF PARTICLE IN MilLIMETERS
SAND
FINE MEDIUM COARSE
152
GRAVEL
FINE COARSE
.COBBlES
GRAVEL 40
'l\
SAND
'l\
47 'l\
SILT AND eLA Y
13 'l\
'l\
L10UID LIMIT
PLASTICITY INDi:X
SAMPLE OF Very gravelly
silty sand
FROM
Hole) at dept:' 24.5'
2" HH 1HR
45 MIN 15 MIN 60 M1N 9 MIN .. MIN M1N
'200
"00
SIEVE ANALYSIS
U.S. STANDARD SERIES CLEAR SQUARE OPENINGS
'1.
"SO '''0 '30 '16 "S "4 ""., Jo'.H l'1,M 3" 5"6"
HYDROMETER ANALYSIS
TIME READINGS
"
z
iii
'"
<
~
~
z
w
"
<<
w
~
I , ,
100 .
90 ,
..
7.
..
30 7
20
I.
. ,
00' 002 OOS 009 .,. .37 .7< 14~ 2'.H S90 '19 r/3d 4 If. '51 191 "" '" 171 7
.
20
30
o
..w
Z
'.
~
w
50<<
~
Z
w
.."
<<
W
~
.
80
90
00
CLAY TO SILT
47 7n
DIAMETER OF PARTICLE IN MILLIMETERS
SANC)
MEOI~IM
1 ~.;>
.'INE
COAIl$(
GH.........U
flN( COAllS(
COl\illfS
GRAVEL I 6
LIOUID LIMIT
%
SAND
%
76 %
SIL T AND CLAY
3 .%
%
PLASTICITY INDEX
SAMPLE Of
S I i 'Jill I Y ,i I t Y
~r".Jvl~ll.,. S...1Ih.i
F!tOM
I!ol(~ :; at dc:H:l ]:),51
1122 8:;
GRADATION TESTRESUL TS
F i9... .... _'-'--:.,8__.
,,;'
.'
chen and associates, inc.
HYDROMETER ANAL VSI$
TIME READINGS
SIEVE ANAL VSIS
uS Sf ANDAnD SERIES CLEAR SQUARE QPENINGS
"0
24HR 7 HR
,
"'0
80
S-MIN 15M1N 60 M1N "9 MIN 4 MIN lM1N "00 "00 '50 '40 "30 .,. '" " ,. ".h 1'},>" ,.. 5"6' B"
0
,
7
03' ". 291 590 '.>Il ". 9.52 38.' . ,
0 ,002 005 009 00' 0" U9 19.1 16.2 127 ,
o
90
20
70
'"
~60
..
"
<
~'"
~
z
w
~ -40
w
~
'"
a
w
.oz
;;
~
w
"'~
~
z
w
"'u
~
w
~
o
20
80
00
'"
o
00
00
CLAY T051&:,T
,-42 2.0
DIAMETER OF PARTICLE IN MilLIMETERS
SAND
FINE MEDIUM COARSE
152
GRAVEL
FINE COARSe
COBBLES
L1aUID LIMIT
SAND
..
92 ..
SILT AND CLAY
7
..
GRAVEL ~
PLASTICITY INOt!X
..
SAMPLE OF
SI ightly si Ity sand
FROM
Hole 5 at depth 39.;'
HYDROMETER ANALYSIS
TIME REAOINGS
2-4HH 7HR
-4S MIN 15 M 60 MIN 9 MIN -4 MIN 1 MIN
."'"
'000
SIEVE ANAL YSI$
u.s. STANDAROSERIES ClEAR SQUARE OPENINGS
"0
'SO '-40'30 '16 "8 '-4 ""., l'oM l'h~ J~ SM6"
"
z
..
"
<
~
~
z
w
U
~
w
~
'N 1 ,
100 0
90 ,
80
'0
-
'0
3() 7
20
I.
0 ,
00' 00' 005 009 .019 037 0" ". "" 590 ". .; '" 476 9~ .., "" ,., 127 ~'2
,
o
20
30
a
.o'J!
;;
~
w
"'~
~
z
w
oou
"
w
~
o
80
90
00
CLAY TO SILT
, ,.
DIAMETER OF PARTICLE IN MILLIMET ERg
5ANO
MEDIUM
152
FIN[
COAHSf
GHAvn
~'INf: COAHSE
COOOLES
GRAVEL
..
SAND
..
..
SIL T AND CLAY
..
LIQUID LIMIT
PLASTiCITY INDEX
..
$AMPL E OF
FOOM
II::>::> 85
GRADATION TEST RESUL TS
F. {,_C
Ig.-_.~
.
.'
CI)
f-
-l
::>
CI)
w
0:
f-
.<1) CI)
W W
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MEMORANDUM
TO:
Aspen city Council
Robert S. Anderson, Jr., City Manager f.7rr-
Alan Richman, Planning and Development Director ~
THRU:
FROM:
DATE:
Little Nell Hotel Parking Plan Increase
October 7, 1987
RE:
================================================================
SUMMARY: The staff recommends that you grant
request to place an additional 26 parking spaces
Nell Hotel, in partial fulfillment of ASC's
respect to the Aspen Mountain Master Plan.
the applicant I s
below the Little
obligation with
PREVIOUS COUNCIL ACTION: Council approved the Little Nell
Precise Plan on April 14, 1986. Included in the Plan was a
requirement for the applicant to provide 118 parking spaces
subgrade, plus 13 spaces in the drop-off area and 2 service
delivery spaces. This number of parking spaces was in excess of
the number originally proposed by the applicant, and appears to
adequately handle the needs of hotel guests, users of the
commercial space and certain employees of the ski area.
BACKGROUND: On May 6, 1985, the Board of County commissioners
approved the Aspen Mountain Ski Area Master Plan. One condition
of their approval, based on a referral of the Plan to the city,
was that the applicant provide 46 off-street parking spaces to
mitigate the impacts of the ski capacity increase on the mountain
from 3,000 to 4,300 skiers at one time. The condition gave ASC
the option to provide these spaces in a number of ways, including
at the base area, via cash-in-lieu or via construction Off-site,
subject to approval by the City of Aspen.
PROBLEM DISCUSSION: section 24-7.9 of the Municipal Code
provides the Planning Director with the authority to authorize
minor changes to adopted precise plans, if required by engin-
eering standards or other technical design needs not anticipated
during review of the project. The applicant states that due to
detailed soil borings, foundation design and construction
drawings for the hotel, addi tional parking on-site has become
feasible. We believe this situation meets the test for an
amendment which can be approved by the staff.
A drawing of the proposed new parking plan has been submitted to
me, showing 144, rather than 153 subgrade spaces. Therefore, the
maximum number of new spaces we can approve at this time is 26,
not the 35 cited in the attached letter. If additional spaces
are able to be accommodated on the site in later drawings, I will
e.......
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handle such changes at that time.
I am prepared to issue a formal order amending the Precise Plan
to include the 26 spaces below the hotel, unless City Council
. removes this item from the consent agenda and directs me to put
this amendment through the public review process. please be
aware that if this cannot be approved by the Planning Director,
section 24-7.9 requires all other amendments to go through the
full conceptual and precise plan review, a four step process.
Requiring this type of review will effectively kill the proposal,
as it will not be possible to design the hotel for construction
in 1988 to include these spaces.
The reasons that I believe this minor amendment should be
approved are as follows:
1. There is nothing in the approved SPA agreement pre-
cluding provision of these spaces on-site. The agreement
includes a condition that 46 spaces be provided, as per the
County approval, but places no limits on their location.
2. The 46 spaces were required to offset additional ski
area impacts. Since we know that many skiers drive right to the
base area in search of parking, provision of the spaces by ASC
will help to mitigate the effects of the ski area on surrounding
streets and on circulation in the neighborhood.
3. provision of these spaces in the hotel guarantees that
they will be provided in the most timely manner for the commun-
ity. While the community may be moving towards development of a
parking facility on its own, there is presently no guarantee that
such a facility will be built. I would suggest, however, that if
the public facility moves forward and the hotel is delayed, we
retain our ability to request cash from ASC for all 46 spaces,
and not just the 20 which are not yet designated for development.
4. Since the spaces are all to be subgrade, there will be
no visible change to the hotel as approved by Council.
There are several issues which are raised by the applicant's
letter. First, there is a statement about rental of the spaces.
From comments received from both Jay Hammond and Tom Baker, I
believe long term rental of the spaces should be precluded. Our
studies demonstrate that rented spaces are occupied far less
frequently than are spaces open to the general public. Further,
these spaces are intended to mitigate the impacts of ski area
expansion, and should therefore be open, at least during the ski
season. We will require these spaces to be available on this
basis as a condition of our approval.
The second issue is that of fees. Jay questions the appropriate-
ness of charging a fee for public parking. I feel that the SPA
Plan gives me no guidance in this regard. Further, it is unclear
whether or not we will be charging fees if a public structure is
,.i-<...
.-,
built. council could choose to add a condition requ~r~ng the
applicant to keep the fees for these spaces in line with any fees
which we charge in a public structure, if one is built.
ALTERNATIVES: The alternatives available to Council are:
1. Leave this item on the consent agenda, in which case it
will be approved subject to the conditions listed below.
2. Remove this item from the consent agenda and place it on
the regular agenda, to provide direction to staff as to revised
or additional conditions.
3. Remove this item from the consent agenda and place it on
the regular agenda, to direct staff not to approve this applic-
ation, but instead to have it processed as a substantial amend-
ment to an approved SPA.
RECOMMENDATION: Staff recommends that you leave this item on the
consent agenda, allowing the addition of 26 public spaces to the
Little Nell Hotel parking garage, in partial fulfillment of ASC's
46 space obligation, subject to the following conditions:
1. If construction of a public facility precedes con-
struction of the Little Nell Hotel, then the City reserves the
right to request cash payment for all 46 spaces.
2. There shall be no long-term rental of the pUblic parking
spaces during the traditional Thanksgiving to Easter ski season.
parknell
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ASPEN SKIING COMPANY
Post Office Box 1248
117 Aspen Airport Business Center
Aspen, Colorado 81612
(303) 925-1220
II September 1987
Mr. Alan Richman, Director
Aspen/Pitkin Planning Office
130 South Galena
Aspen, CO 81611
..
Dear Alan:
I am writing to formally request a minor, technical amendment
to our SPA precise plan approval for the Little Nell Hotel.
Specifically, we are requesting a plan amendment to permit
the addition of 35 structured parking spaces under the hotel.
In addition, subject to the conditions outlined below, we
are seeking agreement with the City and County to allow the
construction of these spaces to meet, in part, our commitment
to public parking from the Aspen Mountain Ski Area Master Plan
approval.
As you may recall, our final Little Nell SPA approval called
for the construction of 118 spaces in levels -10, and -20 of
the Hotel. For structural and cost reasons, we felt that 118
was the maximum physical plan achievable on the site. With
the benefit of more detailed soil borings, foundation design
and construction drawings for the Hotel, we now feel it is
feasible and appropriate to add parking to the site. A lower
level parking plan is attached which depicts our original
parking plan and the proposed addition.
We plan to manage these spaces as follows:
HOTEL
Hotel Guest 67 spaces*
Retail (Employees, public) 17 spaces*
Restaurant/Bar 5 spaces*
Employees 5 spaces*
SKI AREA ADMINISTRATION 7 spaces*
GENERAL PUBLIC PARKING (fee) ~spaces*
TOTAL 118 spaces
GENERAL PUBLIC PARKING (fee) 35 spaces
NEW TOTAL 153 spaces
*Provided for SPA approval.
ASPEN MOUNTAIN. BRECKENRIDGE' BUTTERMILK MOUNTAIN' SNQWMASS
,......
.-~
Mr. Alan Richman, Director
II September 1987
Page Two
The general public parking spaces will be available on a
rental basis or a first come, first served basis. Also, we
anticipate some trading of spaces between those reserved for
rental and ski area operations. The parking analysis conducted
by TDA (appendix 3 of our SPA submission) outlines a recommen-
dation to use 17 spaces in summer for retail and 7 for ski
operations. It goes on to recommend that this arrangement
reverses in the winter. This is a feature of our parking
plan which we would like to test and evaluate.
As noted above, we are also requesting credit for 35 spaces
against our total commitment of 46 spaces from our previous
AMSAMP approval. We believe that there is sound public policy
rationale to support this request as follows:
I. These new spaces will fulfill the same parking demand
supplied by a public parking structure regardless of
its location and, therefore, alleviate public parking
demand.
2. This plan will locate parking at the skiers destination
and it is, therefore, an optimum location.
3. These spaces will relocate 35 cars from on-street
parking and, therefore, will reduce congestion on Ute
Avenue.
4. There will be no above ground modification in the Little
Nell Hotel Plan.
5. The location of these spaces within the Hotel structure
is consistent the AMSAMP Which Pitkin County approved.
6. To the best of our knowledge, the parking spaces, as
designed and depicted on the attached drawings, conform
to existing City of Aspen Parking Standards.
We appreciate your review of this request and look forward
to a response at your earliest convenience.
,-~
/
Si ~;ye':re ~~//
7~; .,,~.;/.>'
" ///,,/; .
i 1(/' .'
/' Fre<;i/Smith
/ PUiming Director
I '
As:gW
Enclosure
.1""'\
1"""\.
MEMORANDUM
RE:
Alan Richman, Planning Director
Jay Hammond, City Engineering~
October 2, 1987
Nell Hotel Parking Amendment
TO:
FROM:
DATE:
=======================================================~======
Having reviewed the above application from the Aspen Skiing
Company to amend the Little Nell Hotel plan to provide 35
additional on-site parking spaces for public use, the Engineering
Department would offer the following COmments:
I. The plan submitted to our office shows 144 total spaces for
an increase of 26 spaces over the SPA precise plan, not 35 as
indicated in the correspondence.
2. I would question the appropriateness of charging a fee for
public parking. The conditions of approval under the Aspen
Mountain Ski Area Master Plan obligate the Ski Company to provide
46 public parking spaces with no reference to fees for their use.
Charging for parking may discourage use and minimize the benefit
on adjacent streets.
3. I am somewhat confused by the reference in Fred's letter of
September II regarding provision of parking on a "rental" basis.
I would suggest that providing reserved RrentalR spaces again
does not meet the need for public parking by tying up spaces
that mayor may not be used.
Further, the reference to trading spaces between RrentalR and ski
area operations seems inappropriate in that any agreement to
credit the Skiing Company toward its commitment for 46 spaces,
should be based on spaces strictly reserved for public use.
4. Finally, I would note our support for providing at least some
amount of public skier parking on-site to minimize the shuttling
of private cars to and from Little Nell.
JH/co/NellPkingAmend
cc: Chuck Roth
ASPEN SKIING COMPANY
I"'.
,,,",,,, IrUr\'I\[f@T;;:~\:::~ ."".,
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Post Office Sox 1248
117 Aspen Airport Business Center
Aspen, Colorado 81612
(303) 925.1220
20 August 1987
Mr. Alan Richman
Planning Director
Aspen Pitkin County
Planning Office
506 East Main Street
Aspen, CO 81611
..
Dear Alan:
As part of the 1985 Aspen Mountain Ski Area Master Plan
process, which was approved on May 6th of that year by the
Pitkin County Commissioners, certain requirements were
imposed on the Aspen Skiing Company to provide 46 off-street
skier automobile parking spaces. In Exhibit A "Conditions" of
the Board of County Commissioners; Section 1, Paragraph E, it
was discussed that this requirement could be met by providing
on-site automobile parking, off-site automobile parking, or
a cash contribution to the City of Aspen, or a combination
of each method. Further, the conditions suggested that
Aspen Skiing Company, at its discretion, could provide the
off-street automobile parking on site at the base of Little
Nell and this would be subject to appropriate land use approval
by the City of Aspen.
The Aspen Skiing Company is now investigating the opportunities
to construct such parking spaces underground within the Little
Nell Hotel complex. Although we have not done sufficient
technical analysis to confirm that this is a possibility, we
would like to assure ourselves that the requirement and the
commitment that we made to Pitkin County, would be satisfied
with the construction of at least a portion of these spaces
at this location.
I would, therefore, request that we be allowed a discussion
with the appropriate City staff or officials to determine the
conformity of this request. As we are currently planning to
begin construction of our Little Nell Hotel facility in the
Spring of 1988, it is imperative that we begin our final
planning and construction documentation work immediately. I
would,. therefore, suggest that we arrange for these meetings
as soon as it is possible.
ASPEN MOUNTAIN' BRECKENRIDGE. BUTTERMILK MOUNTAIN' SNOWMASS
1""'\
1""'\.
Mr. Alan Richman
20 August 1987
Page Two
It does not appear that all of the 46 spaces can be constructed
within the Little Nell Hotel and it will still be necessary
to provide either additional parking or cash in lieu of, for
the remaining spaces. However, the Aspen Skiing Company is
prepared to meet its commitments and would request only that
we proceed as quickly as possible to help mitigate what we
believe to be an increasingly serious problem within the
downtown area of Aspen.
If you have any questions in this
to contact my office at 925-1220.
from you in tpe very near future.
regard, please do not hesitate
I look forward to hearing
FS:gw
cc: Jerry Blann
Paula Crown
Jeff Rhodes