HomeMy WebLinkAboutB17-0114_B17-0114 Open Hole report_1508275366.pdf H-pKu MAR 5020 County Road 154
Glenwood Springs, CO 81601
Geotechnical Engineering I Engineering Geology Phone:(970)945-7988
Materials Testing I Environmental Fax: (970)945-8454
Email: hpkglenwood@kumarusa.com
Office Locations: Denver(HQ), Parker, Colorado Springs, Fort Collins,Glenwood Springs, Summit County, Colorado
September 8, 2017
Crestone Building Company
Attn: Scott Hoffman
501 West Hallum
Aspen, Colorado 81611
scott@crestonebuilding.com
Project No. 16-7-508.A
Subject: Observation of Excavation, Proposed Residence, Lot 2,Block 6, Bighorn 3rd
Addition,4367 Columbine Drive, Vail, Colorado
Dear Scott:
As requested, a representative of H-P/Kumar observed the excavation at the subject site on
August 31, 2017 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 November 9, 2016, Project No. 16-7-508.
The proposed construction is generally similar to that discussed in our previous report. The
building will be a two story structure over a walkout basement level. Ground floors will be a
combination of slab-on-grade and structurally supported over crawlspace. The building has been
designed to be supported on spread footings using an allowable soil bearing pressure of 2,500
psf, as recommended.
At the time of our site visit, the foundation excavation which was essentially complete had been
cut in multiple levels from about 4 to 20 feet below the adjacent ground surface. Steps in grade
between the levels ranged from about 2 to 5 feet. The soils exposed in the bottom of the
excavation consisted of relatively dense, silty to slightly silty sandy gravel and cobbles with
boulders. 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 2,500 psf. Loose and disturbed soils should be removed in the footing areas
to expose the undisturbed natural coarse granular soils, and the subgrade moistened and
compacted. Other recommendations presented in our previous report which are applicable
should also be observed.
Crestone Building Company
September 8, 2017
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 for
possible changes to recommendations in this letter.
If you have any questions or need further assistance,please call our office.
Sincerely,
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