HomeMy WebLinkAboutObservation of ExcavationKomar & Associates, Inc. ® 5020 County Road 154
Geolechnical and Materials Engineers
1f+Aand 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 Summit County, Colorado
September 12, 2024
Colonna Construction
Attn: Bernie Colonna
P.O. Box 1968
Rifle, Colorado 81650
colonna2012 hotmail.com
Project No. 24-7-110.A
Subject: Observation of Excavation, Proposed Metal Building, Harness Lane, County Road 236,
Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on September 6, 2024 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 March 22, 2024, Project No. 24-7-110. The current
observations are performed in accordance with our agreement for professional engineering
services with Colonna Construction dated September 5, 2024.
We understand the proposed residence has been designed to be founded on spread footings
placed on the natural soils and sized for an allowable bearing pressure of 1,500 psf.
At the time of our visit to the site, the foundation excavation had been cut in one level from 1'/2
to 3'/2 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of relatively stiff/medium dense sandy silt and clay to silty sand. 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 can be used for support of spread footings designed for the recommended
allowable bearing pressure of 1,500 psf with a settlement risk. 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
Colonna Construction
September 12, 2024
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 & Associate:
Robert L. Duran, P.
Rev. by: SLP
RLD/kac
Kumar & Associates, Inc. 0 Project No. 24-7-110.A