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June 16, 2014
Barth Vall
do Keith Revere Enterprises
Attn: Phil Ehne
(coreuere ct� mail.coni)
Job No. 114 233A
Subject: Observation of Excavation, Proposed Addition, West Side of Vall
Residence, 2930 Booth Creek Drive, Lot 1, Block 3, Vail Village 11th
Filing, Vail, Colorado
Gentlemen:
As requested, a representative of Hepworth-Pawlak Geotechnical,Inc. observed the
excavation at the subject site on June 13,2014 to evaluate the soils exposed for
foundation support. The findings of our observations and recommendations for the
foundation design are presented in this report. The services were performed in
accordance with our agreement for professional engineering services to Barth Vall, dated
June 12, 2014.
The proposed addition consists of a small enclosure on the west side of the residence. A
strip footing 4 feet deep and sized for 1,500 psf bearing pressure was designed to support
the addition. Ground floor will be slab-on-grade.
At the time of our visit to the site, the foundation excavation had been cut in one level 4
feet below the adjacent ground surface. A sump and pump had been installed outside of
the footing area for dewatering. The soils exposed in the bottom of the excavation
consisted of relatively dense, slightly silty sandy gravel with cobbles that had been
covered with 2 to 3 inches of crushed 3/4 inch rock. No free water was observed in the
footing excavation and the soils were wet.
Considering the conditions exposed in the excavation and the nature of the proposed
construction, spread footings placed on the undisturbed natural soil designed for an
allowable soil bearing pressure of 1,500 psf should be adequate for support of the
proposed addition. The dewatering should continue until at least the footing concrete is
placed. Crushed rock should be placed to above the water level on the inside, slab-on-
grade area. Backfill should consist of granular soils compacted to at least 95%of
standard Proctor density at a moisture content near optimum. Backfill placed around the
structure should be compacted and the surface graded to prevent ponding within at least 5
feet of the building.
l?riikt:i I- 1 ``I?1'11-L` ; i i-i(),' • Sill'i:T't C?rn, 970-466-199
Barth Vail
June 16, 2014
Page 2
The recommendations submitted in this letter are based on our observation of the soils
exposed within the foundation excavation and do not include subsurface exploration to
evaluate the subsurface conditions within the loaded depth of foundation influence. This
study is based on the assumption that soils beneath the footings have equal or better
support than those exposed. The risk of foundation movement may be greater than
indicated in this report because of possible variations in the subsurface conditions. In
order to reveal the nature and extent of variations in the subsurface conditions below the
excavation, drilling would be required. It is possible the data obtained by subsurface
exploration could change the 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 GEO HNICAL, INC.
P 'e 1.°A
Steven L. Pawlak, P E.f 4r 16222 :*
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Job No. 114 233A
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