HomeMy WebLinkAboutObservation of Excavation1(+AGeotechnical and Materials Engineers 5020 County Road 154
and Environmental Scientists Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumamsa.com
An Employee Owned Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
January 6, 2023
Uriel Mellin
144 Cliffrose Way
Glenwood Springs, Colorado 81601
uriel.mellin(&hotmail.com
Project No. 21-7-313
Subject: Observation of Partial Excavation, Proposed Residence, Lot 17, Callicotte Ranch,
Sopris Lane, Garfield County, Colorado
Dear Uriel:
As requested, the undersigned representative of Kumar & Associates, Inc. observed the
excavation at the subject site on January 6, 2023 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 10, 2021, Project No. 21-7-313.
At the time of our visit to the site, the upper, northern portion of the foundation excavation had
been cut in one level from 7 to 10 feet below the adjacent ground surface. The soils exposed in
the bottom of the excavation consisted of basalt boulders in a clayey silt and sand matrix. No
free water was encountered in the excavation and the soils were slightly moist to moist. Footing
forms were in place and covered with insulating blankets.
The southern, lower level of the excavation is about 10 feet below the upper level and was still
being excavated at the time of our site visit. The excavation conditions in the incomplete lower
level appeared similar to the upper level with a lot of basalt rocks being encountered.
The soil conditions exposed in the upper level of 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 2,000 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
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.
Uriel Mellin
January 6.2023
Page 2
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, Inc.
Daniel E. Hardin, P.E.
Rev. by: SLP
DEH/kac
Kumar & Associates, Inc. Project No. 21-7-313