HomeMy WebLinkAboutObservation of ExcavationK+AGeotechnicaf and Materials Engineers 5020 County Road 154
and Environmental Scientists Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
An Employee Owned Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Sununit County, Colorado
February 23, 2021
Taani Martinez
409 County Road 265
Rifle, Colorado 81650
taanim(&outlook.com
Project No. 20-7-410.A
Subject: Observation of Excavation, Proposed Addition, 409 County Road 265
(Prefontaine Avenue), Rifle, Colorado
Dear Taani:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on February 22, 2021 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 August 6, 2020, Project No. 20-7-410.
At the time of our visit to the site, the foundation excavation had been cut in one level from 2 to
2%2 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of stiff, sandy clayey silt. 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 1,000 psf. Loose and disturbed soils should be removed in the footing areas
to expose the undisturbed natural soils. 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.
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
Taani Martinez
February 23, 2021
Page 2
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,
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Kumar & Associates, Inc. ,; Project No. 20-7-410.A