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Geotechnical 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 Compony www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
April 5, 2021
Jeff and Becky Zimmermann
6936 East Archer Place
Denver, Colorado 80230
jimmermann cr,designworkshop.com
Project No. 20-7-654
Subject: Observation of Excavation, Proposed Residence, Lot 22, Coryell Ranch, 37
Cutbow Lane, Garfield County, Colorado
Dear Mr. & Mrs. Zimmermann:
As requested by Janckila Construction, the undersigned representative of Kumar & Associates,
Inc. observed the excavation at the subject site on March 29 and 31, 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 December 9, 2020,
Project No. 20-7-654.
At the time of our initial visit to the site, the foundation excavation had been cut in two levels
from 1 to 6'/2 feet below the adjacent ground surface. The soils exposed in the bottom of the
excavation consisted of mostly dense, slightly silty, sandy gravel with cobbles. The foundation
subgrade in a small part of the north, entryway area exposed sandy clay soils. We recommended
that the contractor remove the clay below footing areas and expose the underlying gravel soils.
No free water was encountered in the excavation and the soils were slightly moist to moist.
When we visited the site again on March 31 St, we observed that the subgrade in the clay soil
areas had been lowered about 8 inches to expose the underlying dense gravel soils.
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 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 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
Jeff and Becky Zimmermann
April 5, 2021
Page 2
(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.
Daniel
FROM"M"I
cc:
alex@j anckilaconstruction. com)
Kumar & Associates, Inc. 1 Project No. 20-7-654