HomeMy WebLinkAboutExcavation Observation Report 08.31.2015G&ec
HEPWORTH-PAWLAK GEOTECHNICAL
August 31, 2015
Brett Jolley
1288 County Road 245
New Castle, Colorado 81647
bjollev@sopris.net
1 fepaortl�-I'.�++1.�1: Gintechnn..,l. Inc
5020 County IZu.a1 154
GknutxiJ Spnn4,, Ctlur.iJn 81601
Phone- 970.915•79SS
Rix 910-945.8454
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Job No. 114 549A
Subject: Observation of Excavation, Proposed Jolley Residence, Parcel B, Huber
Exemption, 1793 County Road 245, West of New Castle, Garfield County,
Colorado
Dear Brett:
As requested, a representative of Hepworth-Pawlak Geotechnical, Inc. observed the
excavation at the subject site on August 25 and 28, 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 February
23, 2015, Job No. 114 549A.
At the time of our initial visit to the site, the north side of the garage excavation and the
central part of the basement excavation had been dug down to footing grade. The
previous septic tank had been completely removed from the central part of the proposed
basement area. The exposed soils consisted of sandy silty clay. The plans stated that the
footings were to bear on the sandy gravel soils below the clay soils. A meeting was held
at the site with Brett Jolley, Jack Palomino, Dan Hardin of H -P Geotech and Bobby with
Redneck Excavating to evaluate whether the footing cut grades should be deepened to
bear on the gravel or be designed to bear on the upper clay soils. It was decided to bear
on the clay soils and Dale Kaup, structural engineer was informed of this the next day.
When we visited the site on August 28th, the foundation excavation was nearly complete
and had been cut in multiple levels from 4 to 9 feet below the adjacent ground surface.
The soils exposed in the bottom of the excavation consisted of mostly medium stiff to
stiff, sandy silty clay with a small area of silty sandy gravel with cobbles in the east side
of the central basement excavation. 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 1,500 psi Loose and disturbed soils should
be moistened and compacted or removed in the footing areas to expose the undisturbed
Parker 303-841-7119 • Colorado Springs 719-633-5562 • Silverthuioe 973-468-19S9
Brett Jolley
August 31, 2015
Page 2
natural 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 — PAWLAK GEOTECHNICAL, INC.
=11,1 �I
Daniel E. Hardin, P.E.
Rev. by: SLP
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;0 24443 i;
cc: Palomino Design -Build P.C. - Jack Palomino (iack@ palominodesiEnbuild.com)
Kaup Engineering - Dale Kaup (dale@kaupcngineerina.corn)
Job No. 114 549A