HomeMy WebLinkAboutObservation of Excavation 10.13.14HEPWORTH-PAWLAK GEOTECHNICAL
October 13, 2014
Sanchez Drywall, Inc.
Attn: Carlos Sanchez
P.O. Box 209
Silt, Colorado 81652
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Job No. 114 226A
Subject: Observation of Excavation, Proposed Residence, Lot 21, Pinyan Mesa,
Sage Meadow Road, Garfield County, Colorado
Dear Carlos:
As requested, a representative of Hepworth -Pawlak Geotechnical, Inc. observed the
excavation at the subject site on September 26 and October 6, 2014 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
June 30, 2014, Job No. 114 226A.
The proposed residence will be supported by a spread footing foundation placed on 5 feet
of structural fill. The structural fill consists of the on-site soils, moistened and
recompacted to 98% of the maximum standard Proctor density. Foundations placed on
the fill soils were designed for an allowable soil bearing pressure of 1,200 psf.
At the time of our initial visit to the site, the foundation excavation had been cut in two
main levels from 5 to 12Vl feet below the adjacent ground surface. The garage portion of
the excavation had not been completed. The soils exposed in· the bottom of the
excavation consisted of stiff sandy silty clay to clayey silt with scattered gravel. No free
water was encountered in the excavation and the soils were slightly moist.
We returned to the site on October 6 , 2014 to observe the completed fill placement. The
excavation was in two levels about Yi foot to 7 feet below the ground surface. The
footing subgrade appeared to have been compacted. Density testing (reported separately)
indicated that satisfactory compaction had been achieved.
The soil conditions exposed in the excavation are consistent with those previously
encountered on the site and the compacted filJ is suitable for support of spread footings
designed fo r the recommended allowable bearing pressure of 1,200 psf. Other
recommendations presented in our previous rep01t which are applicable should also be
observed.
Sanchez Drywall, Inc.
October 13, 2014
Page 2
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
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-PAWLAK GEOTECHNICAL, INC.
Job No. 114 226A