HomeMy WebLinkAboutcoa.lu.ec.Sunny Park North-Lot 7.1986
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CASELOAD SUMMARY SHEET
City of Aspen
DATE RECENED: /;;"//0/?Ci' ,. .
DATE RECENED COMPLETE: lo.\~'-l~
PROJECT NAME: S~c~1 P:Y-/~Jo;ih Lof ~ .s ,:bd/V':S/~h
APPLICANT: 7u.hL_ ss_T __n{)._LH<e"f- -pf;c-R
Applicant Addcess/Phone:
REPRESENTATNE: /Oh] A/(/wlll~
Repcesentative Addcess/Phone:
6:SE NO. 36 ~(f?'1)86
STAFF: S I
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Type of Application:
1. GMP/Subdiv ision/PUD
1. Conceptual Submission
2. Pceliminacy Plat
3. Final Plat
20
12
6
$2,730.00
1,640.00
820.00
II. Subdivision/PUD
1. Conceptual- Submission
2. Pceliminacy Plat
3. Final Plat
, -1-4
9
6
$1,900.00
1,220.00
820.00
5
$1, 490 ,00
$ 688.00
.35lJ, U 0
III. All "Two Step" A ppl i ca t ion s
IV. All "One Step" Appl ications
V. Refeccal Fees - Env iconmental
Health, Housing Office
11
1. Minoc Appl ications
2
$
50.00
2. Majoc Applications
Referral Fees-
Engineering
Minor Applications
Majoc Applications
5
$ 125.00
80.00
200.00
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P&Z (52) MEETING DhTE: "S~~ ';}.~
DATE REFERRED: /.ili,),/V,je-,
PUBLIC HEARING: YES
IN ITIALS: )It (~ /'
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REFERRALS:
~ City Atty Aspen Consolo S.D. School Distcict
City Engineec Mtn. Bell Rocky Mtn. Nat. Gas
Housing Die. Packs Dept. _ StateHwy Dept (Glenwd)
Aspen ~iatec Holy Ccoss Electcic _ Statellwy Dept (GLJtnJ
City Electdc Fice Macsha11 _ Bldg: ZoningjInspectn
EnviL Hlth. Fice Chief Othec:
Roaring Fork Transit;, Roaring Fork Energy Center
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City Atty City Engineec Building Dept.
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dC;E DISPOSITION: ~'u""1 ~"..K k',), LCT -; 5tA-;J:'.,:" br./!c.
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Reviewed by: Al',i!en P&Z ~~
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1)
A subdivision exception plat shall be submitted
conforming to the requirements of section 20-15 and
specifically including information requested by the
Engineering Department in the August 17, 1985 memoran-
dum.
2)
A statement of subdivision exception shall be filed
with the City Attorney prior to recordation of plat.
The applicant shall submit a specific building envelope
proposal as part of the application for the Greenline
review, and shall submit information regarding the
impacts of proposed development on the slope vegeta-
tion, drainage, and other environmental issues suf-
ficient in detail to conduct the 8040 Greenline Review,
pursuant to section 24-6.2.
The applicant shall work with the Fire Marshall to
determine if a fire hydrant is necessary on the western
lot line near the access road, and shall provide a fire
hydrant if it is deemed necessary. The matter shall be
resolved prior to approval of the 8040 Greenline
Review.
~:Ir~bmttted plat will include language which indi-
ca es th9t the parcel subtracted from Lot 7 is dedica-
t, t the City for public right-of-way.
8040 Greenline Review for Lot 7 will include an
additional subsurface investigation made on the site of
development to evaluate the risk of subsidence due to
underground mining, pursuant to recommendation made by
Chen and Associates in "Subsoil Study and Underground
Mine Works Review: Proposed Residence Lot 7, Sunny Park
North," December 30, 1986.
The applicant shall
subdivision exception
districts created in
property."
state within the statement of
agreement to join any improvement
the future that encompasses this
5) The submitt",d plat shall in.:IIJd",
subtra.:t",d from the lot will bi' di'd. t dstat",m",ntthat th", par.:",l
th - - l.:a '" as a rlght of way for
'" us", and ",njoym",nt of th", publ i,- and that th' I.
IJn"ondit. lid. - " app l.:ant shall
=. lona y an un",'~ulvoca II y giv", an opt ion to thi' r.it t
ac'_"pt th", par.:",' as ad",dicat",d stri'i't. Th. .'-_ - Y 0
also bi' stat'd. th' c-- -- IS agr""m"nt shall
- ''In,, -:.tat",m",nt of Subdivision E:":.:,,,pt ion.
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DEDICATION OF RIGHT-OF-WAY FOR
ROAD AND UTILITY PURPOSES
The 6,900 sq. ft. parcel being subtracted from Lot 7 is hereby
dedicated as a public right-of-way for roadway, drainage and
utility purposes on, over, along, across, under and through the
land described above and on this plat, for the purposes of
installing, constructing, replacing, repairing and maintaining a
public roadway, drainage facilities and underground utilities,
including (but not limited to) water, sewer, electric, gas,
telephone and television lines; together with the right to
ingress and egress for such installation, construction, replace-
ment, repair and maintenance; and owner unequivocally and
irrevocably grants and dedications an option to the city to
accept the aforesaid parcel as a City right-of-way, to be
exercised by written acceptance of the City council.
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MEMORANDUM
FROM:
Aspen City Council
Robert S. Anderson, Jr., City Manager ~~~
steve Burstein, Planning Office ~
TO:
THRU:
RE:
Sunny Park North Lot 7 Subdivision Exception
DATE:
January 21, 1987
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LOCATION: Lot 7, Sunny Park North Subdivision, east of the Park
Circle loop, and up the hillside.
ZONING: R-15A (PUD).
LAND AREA: 15,191 s.f.
APPLICANT'S REQUEST: Pitkin County, owner of the subject proper-
ty, requests approval of subdivision exception for the purpose of
a lot line adjustment. The parcel would be reconfigured to add
6,900 s.f. to the north of the platted lot, and subtract 6,900
s. f. to the south where Park Circle goes through. Approval
given in 1985 expired because a plat was not filed; and the
County would like city Council to reconsider and approve the same
application.
PREVIOUS COUNCIL ACTION: City Council approved the requested lot
line adjustment on September 9, 1985. On August 13, 1984, City
Council approved annexation of the 6,900 square foot parcel of
land situated to the north of lot 7. Council rezoned Lot 7 and
the 6,900 square foot parcel to R-15A(PUD) on October 22, 1984.
The Board of County Commissioners approved a subdivision exemp-
tion on July 8, 1985 to adjust the lot line between the Mollie
Gibson parcel and Lot 7.
PROBLEM DISCUSSION:
A. Referral Comments:
1.
Engineering
submitted in
1987:
Department: The following comments were
a memorandum by Jim Gibbard on January 21,
A. The submitted plat should include language which
indicates that the parcel that has been subtracted
from Lot 7 has been dedicated to the city for
public right-of-way.
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B. The submitted plat should also include in the
Owner's Certificate, language that would indicate
it had been acknowledged by a Notary Public.
C. The applicant should be aware that pursuant to the
criteria for the 8040 Greenline Review, it is
recommended that additional subsurface investiga-
tion be made on the site of development to
evaluate the risk of subsidence due to underground
mining.
B. Planning Office: In the 1985 review of this proposal, the
following issues were discussed: adequacy of access via the
Smuggler Mountain Road, water pressure, fire protection,
environmental concerns related to steep slopes on the
property, and defining a building envelope on the bench in
the eastern portion of the property. It was noted that the
lot being created meets the minimum lot size of 15,000 s.f.
and contains developable site on the bench. The County
committed to maintain the estimated 1,075 linear feet of the
Smuggler Mountain Road to the access road, all within County
property. Concerns with the building location, environmen-
tal hazards and services were to be fully addressed in the
8040 Greenline Review. The prior conditions of approval
(listed 1-4 in staff's recommended motion) are still
applicable in our opinion. It should be noted that Chen and
Associates prepared a subsurface study and underground mine
works review for Lot 7. Based on this report, the Engineer-
ing Department commented that additional subsurface investi-
gation is recommended. This study can be accomplished in
preparation of the 8040 Greenline Review, as was done for
Lot 3 and 5 by the Siegels and smiths.
ADVISORY COMMITTEE VOTE: This application was
expedited review by City Council only; and there
Commission recommendation.
treated as an
is no Planning
RECOMMENDED MOTION:
"Move to approve the requested subdivision exception for Lot
7 of Sunny Park North Subdivision subject to the following
conditions:
1) A subdivision exception plat shall be submitted
conforming to the requirements of section 20-15 and
specifically including information requested by the
Engineering Department in the August 17, 1985 memoran-
dum.
2) A statement of subdivision exception shall be filed
with the City Attorney prior to recordation of plat.
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3) The applicant shall submit a specific building envelope
proposal as part of the application for the Greenline
review, and shall submit information regarding the
impacts of proposed development on the slope vegeta-
tion, drainage, and other environmental issues suf-
ficient in detail to conduct the 8040 Greenline Review,
pursuant to Section 24-6.2.
4) The applicant shall work with the Fire Marshall to
determine if a fire hydrant is necessary on the western
lot line near the access road, and shall provide a fire
hydrant if it is deemed necessary. The matter shall be
resolved prior to approval of the 8040 Greenline
Review.
5) The submitted plat will include language which indi-
cates that the parcel subtracted from Lot 7 is dedica-
ted to the City for public right-of-way.
6) 8040 Greenline Review for Lot 7 will include an
additional subsurface investigation made on the site of
development to evaluate the risk of subsidence due to
underground mining, pursuant to recommendation made by
Chen and Associates in "Subsoil study and Underground
Mine Works Review: Proposed Residence Lot 7, Sunny Park
North," December 30, 1986.
7)
The applicant shall
subdivision exception
districts created in
property."
state within the statement of
agreement to join any improvement
the future that encompasses this
CITY MANAGER'S RECOMMENDATION:
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SB.010
3
pitkin county
506 east main street
aspen, colorado 81611
Public Asset Management Office
December 16, 1986
Mr. Steve Burstein, City Planner
Aspen/Pitkin Planning Office
130 South Galena
Aspen, CO 81611
Dear Steve;
This letter is to formally request that the Aspen City Council
reconsider, approve and sign a plat to be recorded for Lot 7 of
the Sunny Park North Subdivision,
The Sunny Park North Lot 7 Subdivision Exception was previously
reviewed and approved by council on September 4, 1985. Because
of staff changes and other administrative misconnections, the
plat was never formally signed and recorded. According to sub-
section 20-14(e) of the Aspen City Code, "Failure on the part of
the subdivider to record the final plat within a period of ninety
(90) days following approval by the city council shall render the
plat invalid," Reconsideration and approval is therefore
necessary before the plat can be formally accepted and recorded.
Please accept this letter and a check for $350.00 (staff time and
referrals) as a request fnr agenda scheduling.of this matter. If
you have any further questions, or care to request further
information for the agenda packet, please contact me at 925-6612,
Sincerely,
PUBLIC ASSET MANAGEMENT
_ ....---.-....---.....-....:-----
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Tom Newland, Planning
cc: Ann Bowman
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MEMORANDUM
TO: Steve Bucstein, Planning Office
FROM: Jim Gibbard, Engineering Department ~
DATE: January 21, 1987
RE: Sunny Park North Lot 7 Subdivision Exception
--------------------------------------------------
--------------------------------------------------
The Engineering Department has reviewed the above application and
, has the following comments:
1. The submitted plat should include language _which indicates
that the parcel that has been subtracted from lot 7 has been
dedicated to the city for public right of way.
2. The submitted plat should also include in the Owner's Certifi-
cate, language that would indicate it had been acknowledged by a
Notary Public.
3. The applicant should be aware that pursuant to the criteria
for the 8040 Greenline review, it is recommended that additional
subsurface investigation be made on the site of development to
evaluate the risk of subsidence due to underground mining.
j g/lot7
cc: Jay Hammond
MEMORANDUM
FROM:
Ci ty Attoc ney
Ci ty Engineec
Steve Burstein, Planning Office
TO:
RE:
Sunny Park North Lot 7 Subdivision Exception
DATE:
January 2, 1987
================================================================
Attached for your review and comments is an application submitted
by Tom Newland requesting reconsideration and appcoval for
signature and recordation of a plat to Lot 7, Sunny Park North
Subdivision. The project received subdivision exception approval
by Council on September 4, 1985 but due to misconnections, the
plat was never formally signed and recorded.
Please review this material and return your referral comments to
the Planning Office no later than January 12, 1987 so this office
has adequate time to prepare for its pcesentation before City
Council on January 26.
Thank you.
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Chen &~sociates
Consulting Geotechnical Engineers
5080 Road 154
Glenwood Springs, CO 81601
303/945-7458
Casper
Colorado Springs
Denver
Fort Collins
Rock Springs
Salt Lake City
San Antonio
SUBSOIL STUDY AND UNDERGROUND MINE WORKS REVIEW
PROPOSED RESIDENCE
LOT 7, SUNNY PARK NORTH, PARK CIRCLE
ASPEN, COLORADO
PREPARED FOR:
PITKIN COUNTY PLANNING
530 EAST MAIN
ASPEN, COLORADO 81611
ATTEIITION: MS. ANN BOIHlAN
JOB NO. 4 442 86 DECEHBER 30, 1986
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TABLE OF CONTENTS
CONCLUSIONS
PURPOSE AND SCOPE OF STUDY
PROPOSED CONSTRUCTION
SITE CONDITIONS
SUBSOIL CONDITIONS
REVIEW OF MINE WORKINGS AND SUBSIDENCE POTENTIAL
Site Geology
Mine Records Review
Surface Indications of Mining Activity
Potential Impacts of Subsurface Mining
1
1
2
3
4
FOUNDATION RECOMMENDATIONS
FLOOR SLABS
SURFACE DRAINAGE
LIHITATIONS
4
5
5
5
6
()
8
9
10
REFERENCES
1 1
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
FIGURE 4 - GRADATION TEST RESULTS
FIGURE 5 - GRADATION TEST RESULTS
TABLE I - SUMMARY OF LABORATORY TEST RESULTS
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CONCLUSIONS
The subsoils encountered at the site consist
of silty sands and gravels with cobbles and boul-
ders. Foundations for the residence should consist
of spread footings placed on the natural soils
below any existing fill and designed for a maximum
soil bearing pressure of 3,000 psf. Available mine
record maps show that underground mining may extend
beneath the site and the Mollie Gibson Mine 111
shaft may be near the northern lot line. The risk
of future ground subsidence due to the underground
mine workings may be high. Additional investiga-
tions are recommended to better evaluate the risk
of subsidence. Other geotechnical design and
construction considerations for the proposed resi-
dence are presented in the body of this report.
PURPOSE AND SCOPE OF STUDY
This report presents the resul ts of a subsoil study and
underground mine works rev iew for a proposed residence to be
located on Lot 7, Sunny Park North, Park Circle, Aspen, Colo-
rado.
The study was conducted for the purpose of developing
foundation recommendations and included a review of mine records
maps.
The project site is shown on Fig. 1.
The study was
conducted in accordance with our Agreement for Professional
Engineering Services to Pitkin County Planning, dated December 8,
1986.
A field exploration program consisting of exploratory borings
and a field reconnaissance was conducted to obtain information on
subsurface conditions.
Samples obtained during the field explo-
Chen &Associates
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ration were tested in the laboratory to determine classification
and engineering characteristics of the on-site soil. The results
of the field exploration and laboratory testing were analyzed to
develop recommendations for foundation types, depths and allow-
able pressures for the proposed building foundation. The results
of the field exploration and laboratory testing are presented
herein. A review of information on mine workings in the area of
the site was made to evaluate the potential for mine related
subsidence.
This report has been prepared to summarize the data obtained
during this study and to present our conclusions and recommen-
dations based on the proposed construction, the subsurface
conditions encountered and the mine workings information re-
viewed. Design parameters and a discussion of geotechnical
engineering considerations related to construction of the pro-
posed residence are included in the report.
PROPOSED CONSTRUCTION
Specific building plans for the proposed residence had not
been developed at the time of our study. We understand the
findings of our study will be considered in the sale/purchase of
the property in which the County is the seller. We assume the
residence will be two stories of wood frame construction that
will impose relatively light foundation loadings. We also assume
the residence will be located in the flatter part of the lot in
the area of the exploratory borings shown on Fig. 1. Cut depths
Chen & Associates
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to achieve foundation bearing levels are expected to be rela-
tively shallow, to a maximum of about 5 feet.
If building and grading plans for the residence are signifi-
cantly different from those assumed above, we should be notified
to reevaluate the recommendations presented in this report.
SITE CONDITIONS
The subject property consists of a vacant lot near the end of
Park Circle as shown on Fig. 1. Park Circle has been connected
to Park Avenue and the lot is separated from the road by the
Salvation Ditch. The central portion of the lot appears to have
been graded relatively flat. The western part of the lot is a
steep slope down to Park Avenue. We understand the proposed
building site is within the flatter part of the lot. The Smug-
gler Mine is located northeast of the property and access onto
the lot is from Smuggler Mountain Road.
At the time of our field work, the lot was covered with about
1 1/2 feet of snow. Vegetation generally consists of scrub
brush, grass and weeds. Two relatively broad surface depressions
are located on either side of the general building area. The
depressions appear to be a few to several feet deep. We under-
stand the depressions are probably related to past mining
activities in the area. The Salvation Ditch, which is in a
culvert, crosses the toe of the steep slope adjacent to the
western part of the lot.
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SUBSOIL CONDITIONS
The subsoil conditions in the proposed building area were
evaluated by drilling two exploratory borings at the approximate
locations shown on Fig. 1. The borings were drilled to a depth
sufficient for foundation analysis and were not intended to ~
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evaluate mine subsidence potential below the site. Graphic logs
of the subsurface profiles encountered are shown on Fig. 2. As
indicated by the logs, the subsurface profile encountered is
relatively uniform and consists of medium dense to dense silty
sands and gravels with cobbles and boulders. Subsoil studies
performed in the area and on adjacent lots indicate a similar
subsurface profile. The drilling with continuous flight auger
was relatively difficult due to the material size and density and
practical refusal to augers was experienced at a depth of 15 feet
at Hole 1. Free water was not encountered in the borings to the
maximum depth drilled, 26 feet, and the soils were generally
slightly moist.
Samples taken from the borings were returned to our labora-
tory for review by the project engineer and testing. The results
of moisture content and classification testing performed on the
samples are presented in Figs. 4 and 5 and summarized in Table
I. The gradation analyses were performed on material smaller
than 1 1/2 inches.
REVIEW OF MINE WORKINGS AND SUBSIDENCE POTENTIAL
The scope of our study included a review of pUblished data on
the abandoned mine workings in the project area, a review of
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subsidence evaluations for adjacent properties, and a general
review of published data on the site geology.
Site Geologv: The site is located on the northern slope of the
Roaring Fork Valley. Regional geologic mapping (Bryant, 1971)
indicates the surficial soils on the site are glacial morraine
deposits, poorly sorted materials ranging from silt to boulder
sized. The underlying bedrock geology includes a complexly
faulted series of Cambrian to Permian-age sedimentary rocks and
Precambrian igneous rocks. Mineralization of the bedrock Hith
silver, lead and zinc attracted intense mining activity in the
project area, mainly intermittently in the years between 1879 and
1935. Some minor mining activity has continued in the general
area to the present time.
Mine Records Review: Maps of the major mining in the project
area indicate the site is in an area of extensive mine develop-
ment (Rohlfing, 1943 and Bryant, 1972). Mines in the area
followed a steeply, northwestward dipping ore zone and included
at least fifteen levels, extending at least a thousand feet deep,
with miles of tunnels and hundreds of stapes. Although it is
difficult to accurately locate the mine workings with respect to
the property, it appears that the site is in the vicinity of the
workings of the Mollie Gibson Mine. Most of the mining appears
to lie north of the site .
Surface Indications of Mining Activitv: As shown on Fig. 1,
there are two depressions in the ground surface near the site.
It is likely that these features are a result of subsurface
mining. The depression near the northern lot line has been
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identified as the location of the Mollie Gibson 01 shaft (Western
Eneineers, Inc., 1986). The depression near the eastern property
line may be related to an air shaft or incline portal.
potential Imoacts of Subsurface Mining: Based on published data,
the potential impacts that the underground mines may have on site
development cannot be accurately determined. The underground
mining in the area is extensive and mine maps often do not
accurately portray the extent of mining. The risk for ground
subsidence and damage to structures built on the site may be
high. Additional subsurface investigations utilizing deep drill
holes are recommended to better evaluate subsidence risks on the
site.
Sinkholes often occur abruptly in the area of mine shafts,
due to collapse of bridged soil and debris used to backfill the
openings. If the site is not developed, the Mollie Gibson shaft V
may still be a hazard because of this collapse potential.
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FOUNDATION RECOMMENDATIONS
The undisturbed natural soils encountered in the exploratory
borings should be suitable to support a spread footing foundation v'
of a residential structure, Settlement potential of the struc-
ture due to foundation loading on the soil is expected to be
relatively low. Subsidence potential risks due to underground
mine works are presented in the "Rev iew of Mine Horkings and
Subsidence Potential" section of this report. The owner should
consider the mine related risks in the development plans for the
lot.
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The design and construction criteria presented below should
be observed for a spread footing foundation system.
(1) Footings placed on the undisturbed natural soils should be
designed for an allowable soil bearing pressure of 3,000
psf. We expect settlement of foundations designed and
constructed as discussed in this section will be less than
1 inch.
(2) Spread footings should have a minimum width of 16 inches for
continuous footings and 24 inches for isolated pads.
(3) Foundation walls acting as retaining structures should be
designed to resist a lateral earth pressure corresponding to
an equivalent fluid unit weight of at least 40 pcf. The
foundation walls should be backfilled with granular soil like
the on-site soils and compacted to at least 90 percent of
standard Proctor density at a moisture content near opti-
mum. The lateral earth pressure assumes a relatively hori-
zontal backslope grade and a drained condition.
(4) Exterior footings and footings beneath unheated areas should
be provided with adequate soil cover above their bearing
elevation for frost protection. Placement of foundations at
least 42 inches below the exterior grade is typically used in
this area.
(5) Continuous foundation walls should be reinforced top and
bottom to span an unsupported length of at least 10 feet.
Greater foundation reinforcement may be required to mitigate
mine related subsidence potential but should be based
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on the results of additional comprehensive subsurface
investigations.
(6) Areas of loose, disturbed and topsoil materials encountered
within the foundation excavation should be removed and the
footing bearing level lowered to adequate natural bearing
material.
(1) A representative of the soil engineer should observe all
footing excavations prior to concrete placement.
FLOOR SLABS
The natural on-site soils are suitable to support lightly to
moderately loaded slab-an-grade construction (neglecting mine
subsidence potential). To reduce the effects of some differen-
tial movement, floor slabs should be separated froal all bearing
walls and columns with expansion joints which allow unrestrained
vertical movement. Floor slab control joints should be used to
reduce damage due to shrinkage cracking. We suggest joints be
provided on the order of 15 feet on center. The requirements for
slab reinforcement should be established by the designer based on
experience and the intended slab use.
A thin layer of free-draining gravel may be placed beneath
the slabs. This material should consist of minus 2-inch aggre-
gate with less than 50 percent passing the No. It sieve and less
than 12 percent passing the No. 200 sieve.
Fill placed beneath floor slabs should be a granular mate-
rial. The soil engineer should evaluate the suitability of
proposed fill materials. Fill should be placed and compacted to
Chen &Associates
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at least 95 percent of the maximum standard Proctor density near
optimum moisture content. We expect the on-site soils, devoid of
vee,etation, topsoil and oversized rocks, can be used as fill
material.
SURFACE DRAINAGE
The following drainage precautions should be observed during
construction and maintained at all times after the residence has
been completed.
(1) Excessive wetting or drying of the foundation excavations and
underslab areas should be avoided during construction.
(2) Exterior backfill should be adjusted to near optimum moisture
and compacted to at least 95 percent of the maximun standard
Proctor density in pavement areas and to at least 90 percent
of the maximum standard Proctor density in landscape areas.
(3) The ground surface surrounding the exterior of the building
should be sloped to drain away from the foundation in all
directions. We recommend a minimum slope of 6 inches in the
first 10 feet in unpaved areas and a minimum slope of
3 inches in the first 10 feet in paved areas.
(4) Roof downspouts and drains should discharge well beyond the
limits of all backfill.
(5) Runoff from the building drives and landscape areas should
not be directed into the surface depressions at the site.
The depressions may be filled or berms may be constructed to
prevent surface flow into the features.
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LItHTATIONS
This report has been prepared in accordance with generally
accepted soil and foundation engineering practices in this area
for use by the client for design purposes.
The conclusions and
recommendations submitted in this report are based upon the data
obtained from the exploratory borings drilled at the locations
indicated on the exploratory boring plan, mine ~lOrking informa-
tion as referenced herein, and the proposed type of construc-
tion.
The nature and extent of subsurface variations across the
site may not become evident until excavation is performed. If
during construction, fill, soil, rock or water conditions appear
to be different from those described herein, this office should
be advised at once so reevaluation of the recommendations may be
made.
We recommend on-site observation of excavations and
foundation bearing strata by a representative of the soil
engineer.
Additional
comprehensive
subsurface
investigations
are
recommended to better evaluate the risks for ground subsidence
,/
due to underground mining.
CHEN & ASSOCIATES, INC.
BY~;t'-~
Steven L. Pawlak, P.E.
And
By J1~ 1-J ,~~A~ ~u
Roy . Spl e
Eng neering Geologist
SLP/RHS/ec
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REFERENCES
Bryant, 1911, Geologic Map of the Aspen Quadrangle, Pitkin
County, Colorado, USGS Map GQ933.
Bryant, 1912, Map Showing Mines, Prospects, and Areas of
Significant Silver, Lead, and Zinc Production in the Aspen Quad-
rangle, Pitkin County, Colorado, USGS Map 11850.
Lincoln DeVore, 1983, Report on the Surface Geology and
Mining Activity, Centennial Project, Aspen, Colorado.
Rohlfing, 1943, Map of Workings in the Aspen Mining District,
Pitkin County, Colorado.
Western Engineers, Inc., 1986, Geotechnical and Geophysical
Study, Lots 3 and 5, Sunny Park North Subdivision.
Chen &Associates
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APPROXIMATE SCALE: 1"=50'
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44286 CHEN and ASSOCIATES. inc,
LOCATION OF EXPLORATORY BORING fig,1
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444286 CHEN and ASSOCIATES. inc,
Logs of "'ploratory Borings
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Hole :2
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H4286 CHEN and ASSOCIATES. inc,
I.egend and :\otes
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Topsoil; root :one, some organics, disturhed :one,
Sand an.1 Gravel (S~I-GM); silty, cobbles and boulders, medium dense to dense,
slightly moist, yellowish brown.
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Drive sample; standard penetration test (SPT) , 1 3/8-inch 1.0, split spoon
sample.
20/12 Drive sample blow count; indicates that 20 blows of a 140-pound hammer falling
30 inches were required to drive the SPT sampler 12 inches.
T Practical
rig refusal.
~OTES :
1. Exploratory borings were drilled on December 10, 1986 with a 4-inch
diameter continuous flight power auger,
2. Locations of exploratory borings were measured approximately by taping from
features shown on the site plan provided,
3. Elevations of exploratory borings were measured by instrument level and refer
to ground surface at Hole 2 as elevation 100' assumed.
4. The exploratory boring locations and elevations should be considered accurate
- only to the degree implied by the method used.
S. The lines between materials shown on the exploratory boring logs represent the
approximate boundaries between material types and transitions may be gradual.
6. No free water was encountered in the borings at the time of drilling,
Fluctuations in water level may occur with time.
7, Laboraoty Testing Results:
WC = W"ter Content (%)
-200 = Percent passing So, 200 sieve
LI. = Liquid I.imit (OoJ
PI = Plasticity Index (%J
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ASPENIPITKIN PLANNING OFFICE
130 South Gelene Street
Aspen, Coloredo 81611
(303) 925.2020
LAND USE APPLICATION FEES
City
00113 -63721 - 47331 - 52100 GMP/CONCEPTUAL
- 63722 - 47332 - 52100 GMP/PRELIMINARY
- 63723 - 47333 - 52100 GMP/FINAl
- 63724 -47341 - 52100 SUB/CONCEPTUAL
- 63725 - 47342 - 52100 SUB/PRELIMINARY
- 63726 - 47343 - _'00 SUB/FINAL
-,
- 63727 - 47350 - 521D<l" ALL 2-STEP APPLICATIONS
- 63728 - 47360 -52lllo ALL '-STEP APPLICATIONS
/
REFERRAL FEES:
00125 - 63730 - 47380 - 52100 ENVIRONMENTAL HEALTH
00123 - 63730 - 47380 ~ 52100 HOUSING
00115 - 63730 - 47380 - 52100 ENGINEERING
SUB.TOTAL
County
00113 -i3111 -47331
- 63712 - 47332
- 63713 - 47333
- 63714 - 47341
- 63715 - 47342
- 63716 - 47343
- 63717 - 47350
- 63718 - 47360
REFERRAL FEES:
- 63730 - 47380
- 63730 - 47380
- 63731 - 09000
- 63732 - 09000
00125
00123
00113
00113
- 52200
- 52200
- 52200
- 52200
- 52200
r-
-52200
- 52200
- 52200
- 52200
-52200
- 52200
- 52200
PLANNING OFFICE SALES
00113 - 63061 - 09000 - 52200
- 63063 - 09000 - 52200
- 63062 - 09000 - 0??oo
- 63066 - 09000 - 0??oo
- 63069 - 09000
//:"'-" I IVc>r,o//"",.,,f DyI-- TOTAL
Name: l!1 )1;) ('/0 LJ r) 1/:0--P(I,SC11f'Y.'Phone: ,_
Address: Project: '" n I j )"-i r Y Iv" , I
') L, ,. ~s ~j,\ C X(~,)I-
Oale: /.) i r 7l.rr(o
. of Hours: F.;2.!f_
Check #
Cto5n OJ..
Additional Billing:
GMP/GENERAL
GMP/DETAILED
GMP/FINAL
SUBIGEN~'
_._~IDETAILEO
SUB/FINAL
ALL 2-STEP APPLICATIONS
ALL 1-STEP APPLICATIONS
ENVIRONMENTAL HEALTH
HOUSING
ENVIRONMENTAL COORD.
ENGINSRING
SUB-TOTAL
COUNTY COOE
ALMANAC
COMPo PLAN
COPY FEES
OTHER
SUB-TOTAL
.1bl3(8'I) 8b
350 - 00
350 00
. 550 O()
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