HomeMy WebLinkAboutObservation of Excavation 07.21.2023I (lll iiçlf;'ffifruH1i':,Íå
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An Employcc Ownod Compsny
5020 County Road 154
Glenwood Springs, CO 81601
phone; (970) 945-7988
fax: (970) 945-8454
email : kaglenwood@kumarusa.com
www.kumarusa.com
Offrce Locations: Denver (HQ), Parkea Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
July 21,2023
Kate Fratzke
308 Cindys Way
Silt, Colorado 81650
kateb fr atzke @ emai l. c om Project No. 22-7-738.4
Subject:Observation of Excavation, Proposed Residence,308 Cindys Way, north of Silt,
Garfield County, Colorado
Dear Kate:
As requested by Albert Harris, a representative of Kumar & Associates observed the excavation
at the subject site on July 17, 202I to evaluate the soils exposed for foundation support. The
findings of our observations and recommendations are presented in this report. The services are
supplemental to our agreement for geotechnical services with you dated November I7,2022.
V/e previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated February 17,2023, Project No. 22-7-738. The proposed construction is
similar to that discussed in our previous report. Spread footings sized for an allowable soil
bearing pressure of 1,500 psf were designed for foundation support, as recommended with some
risk of settlement.
At the time of our site visit, the foundation excavation had been cut in one level from about 1 to
3 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of stiff, very sandy silty clay. Results of swell-consolidation testing performed on
samples taken from the site, shown on Figure 1, indicate the soils are moderately compressible
under conditions of loading and wetting. No free water was encountered in the excavation and
the soils were slightly 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
Kate Fratzke
July 21,2023
Page 2
bearing pressure of 1,500 psf. The risk of settlement is primarily if the bearing soils were to
become wetted and precautions should be taken to prevent wetting. Loose and disturbed soils
should be removed in the footing areas and the subgrade moistened and compacted. Other
recommendations presented in our previous report which are applicable should also be observed.
The recommendations submiued 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 vanations encountered in the excavation
conditions for possible changes to recommendations contained in this letter.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, lnc.
David A. Young, P.E.
DAY/
attachment Figure 1, Swell-Consolidation Test Results
cc: AlbertHarris (achanis54@gmail.com)
Kumar & Associatos, lnc. o Project No.22-7-738.4