HomeMy WebLinkAboutObservation of Excavation 09.13.2021K+rf ,ffi,ffiffirf'å'*"5020 County Road 154
Glenwood Springs, CO gl60l
phone: (970)945-7989
fax: (970) 945-8454
emai I : kaglenwood@kumarusa.com
www.kumanlsa,com
Glenwood Springs, and Summit Counry, Colorado
Project No. 21-7-709
ån Ënrploycc frncd Compony
Offrce Locations: Denver'(HQ), parker, Colorado Springs, Fort Collins,
September 13,2021
Chris Butler
3367 Grcnd Avenue
Glenwood Springs, Colorado 81601
cbutler I 020@ gmail. com
Subject:
7oz;
observation of Excavation, proposed Barn/ADU, Lot 21, Teller springs, 652Lanat Lane, Garfield County, Colorado
Gentlemen:
As requested, a representative ofKumar & Associates, Inc, observed the excavation at the
subject site on August 30 and September 13,2021to 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 reports dated October 26,lggg,project No. l9g 613 and
October 31, 2005,Project No. 105 75g.
At the time of our visit to the site on August 30, the foundation excavation had been cut in one
level from Yz to l% feet below the adjacent ground surface. The soils exposed in the bottom of
the excavation consisted of silfy sandy gravel and cobbles. On the eastern side of the excavation
near the river, alayet of silty sand was observed in the bottom of the excavation. It was
recommended that this layerbe removed and replaced with the on-site sandy gravel material or
imported road base. At the time of our september 13 visit to the site, the silty sand in the eastem
part of the excavation had been removed and replaced with the compacted on-site sandy gravel
soils' No free water was encountered in the excavation and the soils were slightly moist to
moist' The excavation appeared to have been compacted with a walk-behind sheep,s-foot roller.
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 moistened and compacted or
Chris Butler
September 13,2021
Page2
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 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 ofpractice should be consulted.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, Inc.
Robert L. Duran, P.E.
Reviewed by: DEH
RLD/ljf
Kumar &Associatæ, lnc. ø
Prolect No. 21.2.209