HomeMy WebLinkAboutObservation of Excavation 03.22.2022I( A Kumar & Associates, Inc.• + Geotechnical and Materials Engineers
and Environmental Scientists
An Employee Owned Company
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 22, 2022
MM-Eight Construction
Attn: Trevor Everette
715 Grande A venue
Glenwood Springs, Colorado 81601
trevor@mm-ei gh t.com
Subject:
Dear Trevor:
Project No. 17-7-391.A
Observation of Excavation, Proposed Residence, Lot 65, Filing 2, Pinyon Mesa,
Paintbrush Way, Garfield County, Colorado
As requested, the undersigned representative of Kumar & Associates, Inc. observed the
excavation at the subject site on March 16, 2022 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 July 3, 2017, Project No. 17-7-391.
The proposed house will be a two-story wood frame structure over a basement level with an
attached garage. Foundations were designed for an allowable soil bearing pressure of 1,200 psf
on at least 3 feet of structural fill, as recommended in our previous report.
At the time of our visit to the site, the foundation excavation had been cut in two levels from 7 to
12 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of stiff sandy silty clay. No free water was encountered in the excavation and the soils
were slightly moist.
The soil conditions exposed in the excavation are consistent with those previously encountered
on the site and suitable for support of spread footings placed on at least 3 feet of structural fill
designed for the recommended allowable bearing pressure of 1,200 psf. Loose and disturbed
soils should be moistened and compacted or removed in the footing areas to expose the
undisturbed natural soils prior to structural fill placement. Structural fill, consisting of the onsite
excavated sandy silty clay soils, should be placed in 8-inch lifts and compacted to at least 98% of
the maximum standard Proctor density at a moisture content near optimum. We should be
contacted to provide density testing of the structural fill during placement. 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.
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.
MM-Eight Construction
March 22, 2022
Page2
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,
Kumar & Associates, Inc.
Rev. by: SLP
DEH/kac
Kumar & Associates, Inc. ® Project No.17-7-391.A