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HEKVORTH-PAWLAK GEOTECHNICAL
June 3, 2015
Franz and Susi Zedlacher
c/o Scot Broughton Architects, LLC
Attn: Scot Broughton
P.O. Box 4096
Basalt, Colorado 81621
(sbarcliitecisco(10lnac.com)
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Job No. 114 295A
Subject: Observation of Excavation, Proposed Residence, Lot 8, Filing 8, Elk
Springs, 2344 Elk Springs Drive, Garfield County, Colorado
Dear Mr. and Mrs. Zedlacher:
As requested by Brett Armstrong, a representative of Hepworth-Pawlak Geotechnical,
Inc. observed the excavation at the subject site on June 3, 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
August 22, 2014, Job No. 114 295A. The current site observation was conducted as
additional services and in accordance with our proposal for services with you dated May
16, 2014.
At the time of our visit to the site, the foundation excavation had been cut in one main
level from 2 to 8 feet below the adjacent ground surface and was mostly completed. Two
small areas stepped down at the southeast corner. The soils exposed in the bottom of the
excavation generally consisted of calcareous basalt cobbles and boulders in a sandy silt
and clay matrix. Calcareous gravelly sandy silt and clay was observed along the eastern
part of the excavation. We understand the excavation was advanced by hydraulic
chipping and utility trenches required blasting. No free water was encountered in the
excavation and the soils were slightly moist to 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 2,000 psf. Loose and disturbed soils in the
footing areas should be moistened and compacted or removed to expose the undisturbed
natural soils. Other recommendations presented in our previous report which are
applicable should also be observed.
The recommendations submitted in this letter are based an our observation of the soils
exposed within the foundation excavation and the previous subsurface exploration at the
Parker 303-841-7119 • Coloradlo Springs 719-63 3-5562 • Silverthorne 970-468-1959
Franz and Susi Zedlacher
June 3, 2015
Page 2
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.
S incerely,
HEPWORTH — PAWLAK GEOTECHNICAL, INC.
Reviewed by:
LEElksw
Job No. 114 295A
rAS 411.
Steven L. Pawlak, P.E. 'Oci 16222
•
1411-041
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cc: Brett Armstrong — (btu .b.net)