HomeMy WebLinkAboutExcavation Observation 03.17.2023
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
March 17, 2023
Giard Homes
Attn: Roger Giard
1431 Airport Road
Rifle, Colorado 81650
roger.giard@giardhomes.com
Project No. 22-7-199.01
Subject: Observation of Excavation, Proposed Residence, Lot E-7, Aspen Glen, 38 Puma
Lane, Garfield County, Colorado
Dear Roger:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on March 8, 2023 to evaluate the soils exposed for foundation support. The findings
of our observations and recommendations are presented in this report. The services are
supplemental to our agreement for professional services to Giard Homes dated February 23,
2022.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated May 11, 2022, Project No. 22-7-199. The proposed construction is
similar to that discussed in our previous report. The building has been designed to be supported
on spread footings sized using an allowable soil bearing pressure of 1,500 psf, as recommended
with some risk of settlement.
At the time of our site visit, the foundation excavation which was essentially complete had been
cut in generally one level from about 2½ to 3½ feet below the adjacent ground surface. There
was minor cut in the garage slab area. The soils exposed in the bottom of the excavation
consisted primarily of stiff to very stiff, sandy silty clay. Along the north side of the excavation
was a soft muddied subgrade area that we recommended be removed and replaced with rocky
soils. Results of swell-consolidation testing performed on samples taken from the site, shown on
Figure 1, indicate the soils are moderately compressible under conditions of loading and wetting
with a nil to low hydro-compression potential. The exposed soils are not expansive. No free
water was encountered in the excavation and the soils were generally moist expect for the wet
muddied subgrade area.
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 psf. Any muddied and all loose disturbed soils should be removed in
the footing areas to expose the firm undisturbed natural soils, and the subgrade compacted. The
bearing soils should be protected from frost and concrete should not be placed on frozen soils.
Other recommendations presented in our previous report which are applicable should also be
observed.
Kumar & Associates