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HEPWORTH—PAWLAK GEOTECHNICAL
March 23, 2015
Cecilia Hadley
7 Meadow Wood Road
Glenwood Springs, Colorado 81601
(chadley37 hotmail.com)
Hepworth-Pawlak Geotechnical, Inc.
5020 County Road 154
Glenwood springs, Cotorado 81601
Phone: 970-945-7988
Fax: 970-945-8454
Email: hpgeorc?hpgeotech.com
Job No. 114 409B
Subject: Observation of Excavation, Proposed Residence, Lot 1, Four Mile Ranch
Subdivision, Red Cliff Circle, Garfield County, Colorado
Dear Ms. Hadley:
As requested by Scott Baiter, a representative of Hepworth-Pawlak Geotechnical, Inc.
observed the excavation at the subject site on March 18, 20I5 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
October 21, 2014, Job No. 114 409A.
The proposed residence will be a one story wood frame structure over a crawlspace. The
attached garage will have a second story over it and will have a slab -on -grade floor.
Foundations were designed to be placed directly on the natural clay soils with an
allowable soil bearing pressure of 1,500 psf with some risk of settlement if the bearing
soils become wet.
At the time of our visit to the site, the foundation excavation was about 85% complete
and had been cut in two levels from 11/2 to 3 feet below the adjacent ground surface. The
garage area was still being completed. The soils exposed in the bottom of the excavation
consisted of medium stiff, slightly sandy silty clay. Results of swell -consolidation testing
performed on two samples taken from the site, shown on Figure 1, indicate the soils have
low compressibility under light loading and moderate compressibility under increased
loading after wetting. No free water was encountered in the excavation and the soils were
moist.
The soil conditions exposed in the excavation are consistent with those previously
encountered on the site and suitable for support of spread footings designed for the
recommended allowable bearing pressure of 1,500 psf with some risk of settlement,
particularly if the bearing soils become wet. Loose and disturbed soils should be
removed in the footing areas to expose the undisturbed natural soils. The bearing soils
should be protected from frost and concrete should not be placed on frozen soils. The
recommendations contained in the Surface Drainage section of our previous report
should be followed to reduce the risk of long term settlement due to wetting of the
Cecilia Hadley
March 23, 2015
Page 2
bearing soils. 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 subsurface exploration 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.
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
concerned about MOBC, then a professional in this special field of practice should be
consulted.
If you have any questions or need further assistance, please call our office.
Sincerely,
HEPWORTH - PAWLAKa b ICAL INC.
• erF
Daniel E. Hardin, P.E.I 444 i
.orti ? 7//5414'
rtese
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attachment Figure 1 - SwerePeATiolidation Test Results
cc: Batter Construction - Scott Balzer (tuI?LLut cr.coln)
Jordan Architecture - Brad Jordan (ford;ui:ILdiitect(rt cltv�,tc�f'kiic.nct
Job Nu. 114 409B