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HEPV/ORTH-PAWLAK GEOTECHNICl\L
June 17, 2015
Rocky Basler
5703 Saddle Creek Trail
Parker, Colorado 80134
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Job No. 108 204A
Subject: Observation of Excavation, Proposed Residence, Lot 9 I, Filing 7, Elk
Springs, 296 Gossamer Road, Garfield County, Colorado
Dear Mr. Basler:
As requested by Chris Shaw, a representative of Hepworth-Pawlak. Geotechnical, Inc.
observed the excavation at the subject site on June 17, 2015 to evaluate the soils exposed
for foundation support. The findings of our observations and recommendations for the
foundation design are presented in this report. We previously conducted a subsoil study
for design of foundations at the site and presented our findings in a report dated May 20,
2008, Job No. l 08 204A.
At the time of our visit to the site, the foundation excavation was about 90 percent
complete and had been cut in three levels from 3 to 8 feet below the adjacent ground
surface. The soils exposed in the bottom of the excavation consisted of basalt cobbles
and boulders in sand, silt and clay matrix. No free water was encountered in the
excavation and the soils were slightly moist to moist. The excavation bases where very
rough due to cobbles and boulders and had not been compacted.
The soil conditions exposed in the excavation are consistent with those previously
encow1tered on the site and suitable for support of spread footings designed for the
recommended allowable bearing pressure of 2,000 psf. Loose and disturbed soils should
be removed in the footing areas to expose undisturbed natural soils. The excavation bases
should be moistened and compacted. Areas over-excavated due to cobbles and boulders
should be returned to grade with concrete or structural fill such as road base. The road
base should be compacted to 98 percent standard proctor density at a moisture content
near optimum. Other recommendations presented in our previous report which are
applicable should also be observed.
The recommendations submitted in this letter are based on our observation of the soils
exposed within the foundation excavation and the previous limited subsurface exploration
Rocky Basler
June I 7, 2015
Page 2
at the site. Variations in the subsurface conditions below the excavation could increase
the risk of foundation movement. We should be advised of any variations encountered in
the excavation conditions for possible changes to recommendations contained in this
letter.
If you have any questions or need further assistance, please call our office.
Sincerely,
HEPWORTH -PAWLAK GEOTECHNICAL, INC.
Louis E. Eller
Reviewed by:
LEE/ksw
cc: Chris Shaw (cs haw S 102w>hotmail.~om)
Joli No . IOS 204.'\
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