HomeMy WebLinkAboutSubsoil StudylGrtffiilffiffi*iiiå**5020 County Road 154
Glenwood Springs, CO 81601
phone: (970)945-7988
fax: (970) 945-8454
email : kaglenwood@kumarusa.com
An Employcc Owncd Gompony www.kumarusa.com
Offrce L,ocations: Denver (HQ), Par*er, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
RECEMED
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SUBSOIL STUDY
FOR FOUNDATION DESIGN
PROPOSED RESIDENCE
LOT 3, SPRTNG RrDGE RESERVE
DRY PARKROAI)
GARFIELD COUNTY, COLORADO
JOB NO. 22-7-146
MARCH 25,2022
PREPARED FOR:
BOULDER CONSTRUCTION SERVICES
ATTN: MATT JURMU
901 COUNTY ROAD 231
srLT, coLoRADO 81ó52
(matt jurmu@Uout¿ercs. coml
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY
PROPOSED CONSTRUCTION
SITE CONDITIONS....
GEOLOGIC HAZARDS REVIEV/
FIELD EXPLORATION..
SUBSURFACE CONDITIONS
DESIGN RECOMMENDATIONS .................
FOUNDATIONS....
FOUNDATION AND RETAINING WALLS
FLOOR SLABS
I
1
I
.-2-
",
F,
3-
3-
4-
5-
5-
6-
LIMITATIONS .-6-
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
APPENDIX A _ HEPV/ORTH-PAWLAK GEOTECHNICAL, JUNE 30,2004, ASSESSMENT
OF ROCKFALL RISK TO LOTS 1 _ 6, JOB NO. IOI 126.
Kumar & Associates, lnc. o Project No. 22-7'146
PURPOSE AND SCOPE OF STUDY
This report presents the results of a subsoil study for a proposed residence to be located on Lot 3,
Spring Ridge Reserve, Dry Park Road, Garfield County, Colorado. The project site is shown on
Figure 1. The purpose of the study was to develop recoûrmendations for the foundation design.
The study was conducted in general accordance with our proposal for geotechnical engineering
services to Boulder Construction dated January 31,2022. Hepworth-Pawlak Geotechnical
previously performed a preliminary geotechnical study for the subdivision development and
presented the findings in a report dated February 26,2001, Job No. l0l 126 and updated the
study in a report dated June 22,2004.
A field exploration program consisting of exploratory borings was conducted to obtain
information on the subsurface conditions. Samples of the subsurface materials obtained dwing
the field exploration were tested in the laboratory to determine their classification and other
engineering characteristics. The results of the field exploration and laboratory testing were
ana|yzedto develop recoÍrmendations for foundation types, depths and allowable pressures for
the proposed building foundation. This report summarizes the data obtained during this study
and presents ow conclusions, design recoÍlmendations and other geotechnical engineering
considerations based on the proposed construction and the subsurface conditions encountered.
PROPOSED CONSTRUCTION
Building plans were prelimrnary atthe time of our study. [n general, the proposed residence will
be a one and two-story wood-fi'ame structure partly above a walkout basement level with an
attached garage and located as shown on Figure 1. Ground floors could be slab-on-grade or
structural above crawlspace. Grading for the structure is assumed to be relatively minor with cut
depths between about 2 to I feet. We assume relatively light foundation loadings, typical of the
proposed type of construction.
If building loadings, location or grading plans change significantly from those described above,
we should be notified to re-evaluate the recommendations contained in this report.
SITE CONDITIONS
The property was vacant at the time of our field exploration. The site is vegetated with grass,
weeds and sage brush with scrub oak and juniper trees within and above the building area. The
ground surface in the building area slopes moderately down to the northeast at about 20% wtth
about 10 feet of elevation difference across the building fooþrint. The grade steepens in the
upper lot area to around 30o/o or more. Maroon Formation sandstone is exposed on the hillside to
the west of the lot.
Kumar & Associales, Inc. o Project No. 22-7.1¡f6
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GEOLOGIC HAZARDS REYIEW
Hepworth-Pawlak Geotechnical (now Kumar & Associates, Inc.) previously conducted an
assessment of rockfall risk to Lots I - 6, Spring Ridge Reserve and presented the findings in a
report dated June 30, 2004, Job No. I0l 126 (attached).
W'e have reviewed the previous assessment and recommendations that the allowable building
area on the reviewed lots (including Lot 3) be limited to the less steep parts of the lots and at
least 50 feet downhill from the current upperbuilding envelope line of Lots l-5. Based on our
review of the previous report and our field observations on February 21,2022, we aglee with the
previous assessment and recommend that the proposed building on Lot 3 be limited to at least
50 feet away (northeast) from the current upper building envelope line on Lot 3 to avoid the
potential rockfall hazard. The building location plan provided for Lot 3 (Figure I attached)
shows the proposed building to be at least 50 feet from the uphill building envelope line
consistent with the recornmended setback distance.
FIELD EXPLORATION
The field exploration for the project was conducted on February 21,2022. Thlee exploratory
borings were drilled at the locations shown on Figure I to evaluate the subsurface conditions.
The borings ïvere advanced with 4-inch diameter continuous flight augers powered by a track-
mounted CME-45 drill rig. The borings were logged by a representative of Kumar & Associates.
Samples of the subsoils were taken with a 2-inch I.D. spoon sampler. The sampler was driven
into the subsurface materials at various depths with blows from a 140 pound hamms falling 30
inches. This test is similar to the standard penetration test described by ASTM Method D-l586.
The penetration resistance values are an indication of the relative density or consistency of the
subsoils and hardness of the bedrock. Depths at which the samples v/ere taken and the
penetration resistance values are shown on the Logs of Exploratory Borings, Figure 2. The
samples were returned to our laboratory for review by the project engineer and testing.
SUBSURF'ACE CONDITIONS
Graphic logs of the subsurface conditions encountered at the site are shown on Figure 2. The
subsoils encountered, below about I foot of topsoil, consist of medium dense, silty sand with
gravel and cobble size rock fragments to depths of about 2 to 3% feet overþing weathered
siltstone to very hard sandstone bedrock down to the boring depths of 11 to 18 feet. Drilling in
the bedrock was difficult due the its hardness and likely cemented condition and practical auger
drilling refusal was encountered in the deposit.
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Laboratory testing performed on samples obtained from the borings included natural moisture
content and density and finçr than sand size gradation analyses. The laboratory testing is
summarized in Table 1.
No free water was encountered in the borings at the time of drilling and the subsoils and bedrock
were slightly moist.
F'OUNDATION BEARING CONDITIONS
The upper sand soils are variable in depth and relatively compressible compared to the
underlying bedrock materials especially if the soils become wetted. A lower settlement risk
foundation support can be achieved by extending the bearing down into the underlying bedrock
which will likely be encountered for the expected cut depth into the hillside. In sub-excavated
areas down to bedrock, structwal fill could be used to reestablish design bearing level.
Excavation into the bedrock will be diffrcult and could require blasting, chipping or splitting.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory borings and the nafure of
the proposed construction, the building can be founded with spread footings bearing on the
natural sand soils or bedrock with a low risk of differential settlement across the building.
The design and construction criteria presented below should be observed for a spread footing
foundation system.
1) Footings placed on the undisturbed natural sand soils or bedrock should be
designed for an allowable bearing pressure of 2,000 psf. Based on experiencç, we
expect settlement of footings designed and constructed as discussed in this section
will be about I inch or less and could be differential between soil and rock
bearing areas. Footings placed entirely on bedrock can be designed for an
allowable bearing pressure of 5,000 psf with less than I inch of settlement
potential.
2) The footings should have a minimum width of 16 inches for continuous walls and
2 feet for isolated pads.
3) Exterior footings and footings beneath unheated areas should be provided with
adequate soil cover above their bearing elevation for fi'ost protection. Placement
of foundations at least 36 inches below exterior grade is typically used in this
area.
4) Continuous foundation walls should be heavily reinforced top and bottom to span
local anomalies such as by assuming an unsupported length of at least 12 feet.
Kumar & Associates, lnc.6 Project No.22-7-146
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Foundation walls acting as retaining structures should also be designed to resist
lateral earth pressures as discussed in the "Foundation and Retaining Walls"
section of this report.
The topsoil and any loose or disturbed soils should be removed and the footing
bearing level extended down to the firm natural soils. The exposed soils in
footing area should then be moistened and compacted. Structural fill placed
below footing areas can consist of the onsite sand soils compacted to at least 98%
of standard Proctor density at near optimum moisture content.
A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
FOUNDATION AND RETAINING V/ALLS
Foundation walls and retaining structures which are laterally supported and can be expected to
undergo only a slight amount of deflection should be designed for a lateral earth pressure
computed on the basis of an equivalent fluid unit weight of at least 50 pcf for backfill consisting
of the on-site soils. Cantilevered retaining structures which are separate from the residence and
can be expected to deflect sufficiently to mobilize the full active earth pressure condition should
be designed for a lateral ealth pressure computed on the basis of an equivalent fluid unit weight
of at least 40 pcf for backfill consisting of the on-site soils. Backfill should not contain organics
or rock larger than about 6 inches.
All foundation and retaining structures should be designed for appropriate hydrostatic and
surcharge pressures such as adjacent footings, trafftc, construction materials and equipment. The
pressures recoÍtmended above assume drained conditions behind the walls and a horizontal
backfill surface. The buildup of water behind a wall or an upward sloping backfill surface will
increase the lateral pressure imposed on a foundation wall or retaining structure. An underdrain
should be provided to prevent hydrostatic presswe buildup behind walls.
Backfill should be placed in uniform lifts and compacted to at least 90% of the maximum
standard Proctor density at near optimum moisture content. Backfill placed in pavement and
walkway areas should be compacted to at least 95o/o of the maximum standard Proctor density.
Care should be taken not to overcompact the backfill or use large equipment near the wall, since
this could cause excessive lateral pressure on the wall. Some settlement of deep foundation wall
backfill should be expected, even if the material is placed correctly, and could result in distress to
facilities constructed on the backfill.
The lateral resistance of foundation or retaining wall footings will be a combination of the
sliding resistance of the footing on the foundation materials and passive earth pressure against
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Kumar t Associates, lnc. o Project No.22-7-l¡16
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the side of the footing. Resistance to sliding at the bottoms of the footings can be calculated
based on a coefficient of friction of 0.45. Passive pressure of compacted backfill against the
sides of the footings can be calculated using an equivalent fluid unit weight of 400 pcf. The
coefficient of friction andpassive pressure values recommended above assume ultimate soil
strength. Suitable factors of safety should be included in the design to limit the strain which will
occur at the ultimate strength, particularly in the case of passive resistance. Fill placed against
the sides of the footings to resist lateral loads should be a granular material compacted to at least
95o/o of the maximum standard Proctor density at a moisture content near optimum.
FLOOR SLABS
The natural on-site soils, exclusive of topsoil, can be used to support lightly loaded slab-on-grade
construction. To reduce the effects of some differential movement, floor slabs should be
separated from 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. The requirements for joint spacing and slab reinforcement should be established by the
designer based on experience and the intended slab use. A minimum 4-inch layer of relatively
well graded sand and gravel such as road base should be placed beneath slabs for support. This
material should consist of minus 2-inch aggregate with at least 50% retained on the No. 4 sieve
and less than 12% passing the No. 200 sieve. The gravel layer below the basement slab should
be relatively free draining with less than2Yo passing the No. 200 sieve,
All fill materials for support of floor slabs should be compacted to at least 95o/o of maximum
standard Proctor density at a moisture content near optimum. Required fill can consist of the
onsite soils devoid of vegetation, topsoil and oversized þlus 6-inch) rock.
UNDERDRAIN SYSTEM
Although free water was not encountered during our exploration, it has been our experience in
the area and where bedrock is shallow that local perched groundwater can develop during times
of heavy precipitation or seasonal runoff. Frozen ground during spring runoffcan create a
perched condition. We recommend below-grade construction, such as retaining walls,
crawlspace and basement areas be protected from wetting and hydrostatic pressure buildup by an
underdrain system.
The drains should consist of drainpipe placed in the bottom of the wall backfill surrounded above
the invert level with free-draining granular material. The drain should be placed at each level of
excavation and at least 1 foot below lowest adjacent finish grade and sloped at a minimum lo/oto
a suitable gravity outlet. Free-draining granular material used in the underdrain system should
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contain less than 2o/opassingthe No. 200 sieve, less than 50% passing the No. 4 sieve and have a
maximum size of 2 inches. The drain gravel backfïll should be at least l% feet deep.
SURFACE DRAINAGE
Proper surface grading and drainage will be critical to limiting subsurface wetting below the
building. The following drainage precautions should be observed during construction and
maintained at all times ¿fter the residence has been completed:
1) Inundation 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 95o/o of the maximum standard Proctor density in pavement and slab areas
and to at least 90% of the maximum standard Proctor densify in landscape areas.
3) The ground swface surrounding the exterior of the building should be sloped to
drain away from the foundation in all directions. We recommend a minimum
slope of 12 inches in the first 10 feet in unpaved areas and a minimum slope of
3 inches in the first 10 feet in paved areas. Free-draining wall backfill should be
covered with fïlter fabric and capped with about 2 feet of the on-site finer graded
soils to reduce surface water infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
5) Landscaping which requires regular heavy irrigation should be located at least
5 feet from foundation walls. Consideration should be given to use of xeriscape
to reduce the potential for wetting of soils below the building caused by irrigation.
LIMITATIONS
This study has been conducted in accordance with generally accepted geotechnical engineering
principles and practices in this area at this time. 'We make no warranty either express or implied.
The conclusions and recommendations submitted in this report are based upon the data obtained
from the exploratory borings drilled at the locations indicated on Figure 1, the proposed type of
construction and our experience in the area. Our services do not include determining the
presence, prevention or possibility of mold or other biological contaminants (MOBC) developing
in the future. If the client is concemed about MOBC, then a professional in this special field of
practice should be consulted. Our findings include interpolation and extrapolation of the
subsurface conditions identified at the exploratory borings and variations in the subsurface
conditions may not become evident until excavation is performed. If conditions encountered
during construction appear different from those described in this report, we should be notified so
that re-evaluation of the recommendations may be made.
Kumar & Associates, lnc. o Project No. 22-?-146
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This report has been prepared for the exclusive use by our client for design pu{pos€s. We are not
responsible for technical interpretations by others of our information. As the project evolvesn we
should provide continued consultation and field sen¡ices during constn¡ction to review and
monitor the implementation of our recourm€,Íldations, and ûo veriry that the recommendations
have been appropriately interpreted. Significant design changes may require additional analysis
or modifications to the recommendations presentd herein. We recommend on-site observation
of excavations and foundation bearing strata and testing of structural fill by a representative of
the geotechnical engineer.
Respectfirlly Submitted,
Kumar & Associates, Inc.
Steven L. Pawlak, P.E.
Reviewd by:
-I
Daniel E Hardin, P.E.
SLP/kac
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Kumar & Associates, lnc. á'Project No. 22-7-146
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Fig. 122-7 -1 46 Kumar & Associates LOCATION OF EXPLORATORY BORINGS
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22-7 -1 46 Kumar & Associates LOGS OF TXPLORATORY BORINGS Fig. 2
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TOPSOIL; ORGANIC SILTY SAND WITH GRAVEL, FIRM, BROWN.
SAND (SM); SILTY, GRAVEL AND COBBLE ROCK FRAGMENTS, MEDIUM DENSE,
SLIGHTLY MOIST, RED-BROWN, ROOTS.
WEATHERED SILTSTONE; HARD, FRACTURED, SLIGHTLY MOIST, MIXED REÐS.
SANDSTONE BEDROCK; VERY HARD, CEMENTED LAYERS, SLIGHTLY MOISÏ, RED TO
DARK RED, MAROON FORMATION.
DRIVE SAMPLE, 2_INCH I.D. CALIFORNIA LINER SAMPLE.
DISTURBED BULK SAMPLE.
50/s DRIVE SAMPLE BLOW COUNT. INDICATES THAT 50 BLOWS OF A 1 4O-POUND HAMMER
FALLING 30 INCHES WERE REQUIRED TO DRIVE THE SAMPLER 5 INCHES.
PRACTICAL AUGER REFUSAL.I
NOTES
1. THE EXPLORATORY BORINGS WERE DRITLED ON FEBRUARY 21, 2022 WITH A 4_INCH DIAMETER
CONTINUOUS-FLIGHT POWER AUGER.
2, THE LOCATIONS OF THE EXPLORATORY BORINGS WERE MEASURED APPROXIMATELY BY PACING
FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED.
3. THE ELEVATIONS OF THE EXPLORATORY BORINGS WERE OBTAINED BY INTERPOLATION BETWEEN
CONTOURS ON THE SITE PLAN PROVIDED.
4. THE EXPLORATORY BORING LOCAÏIONS AND ELEVATIONS SHOULD BE CONSIDERED ACCURATE
ONLY TO THE DEGREE IMPLIED BY THE METHOD USED.
5. THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING LOGS REPRESENT THE
APPROXIMATE BOUNDARIES BETWEEN MATERIAL TYPES AND ÏHE TRANSITIONS MAY BE GRADUAL.
6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORINGS AT THE TIME OF DRILLING,
FLUCTUATIONS IN THE WATER LEVEL MAY OCCUR WITH TIME.
7. LABORATORY TEST RESULTS:
WC = WATER CONTENT (%) (ASTM T2216);
DD = DRY DENSITY (PCt) (ISTU D2216);
-200= PERCENTAGE PASSING N0. 200 SIEVE (ASTM Df140).
22-7 -1 46 Kumar & Associates LTGTND AND NOTTS Fig.3
tcttIünE & Assoehbs, hc.oGeoted¡nical and Materials Engineersand Envircnmental ScientistsTABLE ISUMMARY OF LABORATORY TEST RESULTSNo.22-7-14632I2t3-1443BORII{GDEPTI{6.85.21.73.6f%tNATURALilotsTuREcot{TEI{T111fDcfìI{ATURÁtDRYDENSÍTYl'hlGRAVEL(%)SAI{DGRADATIOTI75242s38PERCENTPASSIiIG ilo.200 stEvEUNCONFINEDcoilPRESStVESIREIIGTHLIQUIDLilÍTPLASNCINDEX'Weathered SiltstoneSandstone\ü/eathered SandstoneSiþ Clayey Sand andGravelSOILTYPE
--,
Hepworth,Pawlak Geotechnical, Inc.
5020 Counq' Road 154
Glenwood Springs, Colorado 81601
Phone: 970-945-7988
HEPWORTH . PAWLAK GEOTECHNICAL Fax 970.945-8454
email: hpgeo@hpgeorech.com
June 30,2004
The Greenwald Children's Trust
c/o Glenwood Brokers, Ltd.
Attn: Pat Fitzgerald
P.O. Box 1330
Glenwood Springs, Colorado 81602
Job No. l0l 126
Subject:Assessment of Rockfall Risk to Lots 1-6, Proposed Springridge Place
Phase II, County Road I25, Garfteld County, Colorado
Dear Mr. Fitzgerald:
As requested, we have conducted a rockfall risk assessment to Lots 1-6 of the proposed
Springridge Place Phase II subdivision. Tïre analysis was perfonned as a supplement to
our previolls geotechnical study for the development (Ilepworth-Pawlak Geotechnical,
2001) and to address General Conditions items 39 and 41 of the Garfield County
resolution for the subdivision approval dated February 3,20A4. This report presents the
findings of our analysis and potential rockfall risk to the site. The analysis was performed
in accordance with our proposal for geotechnical engineering service to The Greenwald
Clrildren's Trust dated May 28, 2004.
Background Infonnation: Our previous reconnaissance in 2001 identified possible
roclcfall impacts to the area of Lots 1-6 on the westem side of the subdivision and on Lots
70-81 on the eastern side of the subdivision. Snow covet at the time of our previous
reconnaissance did not allow for thoro.ugh inspection of the eastern lots. A reconnaissance
of the potential rockfalll ar€as \¡¡¿rs made on May 24,2004. At this time, it is our opinion
that the risk of rockfall to Lots 63-81 is low and rnitigation in that area is not warranted.
The focus of the current analysis is potential rockfall impacts to Lots l-6. The
information obtained from our tecent field review and the Colorado Rockfall Simulation
Prograrn (CRSP Version 4.0) was used in our cunent evaluation ofpotential rockfall risks
to Lots 1-6.
Proposed Development: The development plans for the Phase II part of the Springridge
Place development consist of 8l single family residential lots having sizes ranging from
about I acre to greater than 4 acres. Lots 1-6 will be located uphill of County Road 125
and the rest of the lots will be located in the valley bottom mainly on the easte-m valley
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Parker 303-841-7119 o Colorado Springs 719'633-5562 o Silverthome 970-468-1989
-2-
side. A private roadway system will provide access to the east of County Road 125.
Water and sewer services will be from central systems.
Rockfall Character and Potential: Sandstone outcrops near the top of the ridge on the
west side of the property are potential sources of rockfall that could reach the proposed
building sites on Lots 1-6. Sandstone blocks, many of which are the result ofprevious
rockfall events, are present near the proposed building envelopes on these lots. The
sandstone blocks on the hillside range up to about 2to 3% feet in size. The rocks are
typically between 12 anð22 nches in size at the uphill side of building envelopes on Lots
1-5 and extend typically about 50 feet into the lots. Lot 6 is located across a ravine and is
beyond the potential rockfall runout lirnit'
In our opinion, the upper part of the building envelopes on Lots 1-5 have a risk of rockfall
impact. The recurrence frequency for rockfall in these areas is likely long and may be
greater than 100 years. Although infì'equent, if a rockfall were to reach the proposed
homes it could result in structural damage and could harm the occupants of the buildings.
If this risk is not aceeptable, then rockfall,mitigation to reduce the potential risk should be
considered.
Rockfall Mitigation Concepts: In the unlikely event that a rockfall were to reach the
building area it should be feasible to reduce tlre risk by building lower on the lot,
providing a catching structure located upslope of the proposed home site or by direct
building protection. It should be possible to design the mitigation to provide an acceptable
level of protection to the building and its occupants, but sorne potential for property
damage is typically accepted by the owner.
Mitigation of the rockfall risk by a catching structure or direct protection does not appear
feasible during the subdivision development because the building location and type are
not known. The risk can be reduced by restricting building within about 50 feet of the
current uphill building erwelope line of Lots 1-5. In our opinion, buildings located 50 feet
fiom the upper envelope line and lower in the current building envelopes, and 50 feet
southeast of the northwest building envelope line of Lot l, will have a low risk of rockfall
impact. This essentially places the allowable building area in the flatter alluvial apron
parts of Lots 1,2 and 5 and the less steep parts of the colluvial deposits on Lots 3 and 4.
Potential impacts.to the selected building sites on Lots l-5 and the need for any additional
rnitigation to effectively avoid the potential rockfall hazards should be evaluated using the
Colorado Rockfall simulation Prograrn (CRSP version 4.0) at the tirne of the individual
lot development.
JobNo. l0l 126
eåFnecrr
-.'-
Limitations: This study was conducted according to generally accepted engineering
geology principles and practices in this area, atthis time. lMe make no warranty either
express or implied. The conclusions and recofirmendations submitted in this report are
based on our fi.eld observations, aerial photograph interpretations, interpretations of
previous geologic studies and mapping, and our experience in the area. This report has
been prepared exclusively for our client to evaluate the potential influence of the geology
on the proposed development. The information is suitable for planning and preliminary
design. Ûe are not responsible for technical interpretations by others oiour infonnation.
Geotechnical studies will be needed to provide project specific geologic hazard
mitigation, site grading, and design criteria.
If you have any questions or if we may be of fuither assistance, please let us know
Respectfully Submitted,
HEPWORTH - PAWLAK GEOTECHNICAL, INC
Steven L. Pawlalq P.E.
Rev. by: DEH
SLP/ksw
cc:Sopris Engineering- Attn: Yancy Nichol
REFERENCE
Hepworth-Pawlak Geoteclnic al, Preliminary Ge otechnic al Sndy, Propo sed Spring"ídge
Pløce Phase II, County Road 125, GarfieldCounty, Colorado, JobNo. l0l 126,
reporf dated February 26,2001.
Job No. 101 126
ceeecrr