HomeMy WebLinkAboutObservation of Excavation 06.13.2017H.PVKUMAR
Geolechnlcal Englnaering I Engûnaedng Geology
Materlals Test¡ng I Environmental
5020 County Road 154
Glenwood Springs, C0 81601
Phone: {970) 94$7988
Fax (970) 945-84s4
Email: hpkglenwood@kumarusa.com
June 13,2017
Office Locations: Parker, Glenwood Springs, and Silverlhorne, Colorado
Jack Prock
206 South Linsey Street
Castle Rock, Colorado 80104
cletus64@msn.gom
Project No. 16-7-587
Subjecl.:Observation of Excavation, Proposed Residence, Lot I 15, Ironbridge, 281 Silver
Mountain Drive, Garfield County, Colorado
Gentlemen:
As requested by Justin Soderberg, a represcntâtive of H-P/Kumar observed the excavation al the
subject site on June 8,2017 to evaluate the soils exposed for foundation support. The findings of
our observations and reconrmendations for the foundation design âre presented in this report.
Ìü{e previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated Novcmbcr 23, 2016, Project No, 16-7-581.
The proposed residence is generally the.same as described in our previous report and rvill be
slab-on-grade and crawlspace witlr partial below grade area. Spread footings placed on the
gravel soils and sized for an allowable bearing pres.sure of 3,000 psf as recommended were
designed for the building support.
At the time of our visit to the site, the foundation excavation had been cut in 4 levels from 2 to 6
feet below the adjacent ground surface, The steps in grade rvere about 2 to 4 feet betrveen levels.
The .çoils exposed in the bottom of the exc¿rv¿ltion consisted of relatively dense, slightly silty
sandy gravel and cobbles with small boulders. There were loosened soils in the excavation
bottom lrom the excilvation equipment. No free wilter wrls encounlered in the excavation and the
soils rvere slightly moist.
The sandy grlvel and cobble soil conditions expûsed 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 3,000 psf, Loose disturbed soils in footing are;r"s
should be moistened and compacted. Other recommendations prcsented in our previous report
which are applicable should al.so be observed.
Jack Prock
June 13,2017
Page2
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. ri/e 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.
If you have any questions or need further assistance, please call our office.
Sincerely,
H-P*KUMAR
Steven L. Pawlak, P r 6???*I
6
SLPlkac
cc:Soderberg Con
-¡
l¡
Soderberg {iusti n @ sodelbsrsçqstçnho¡Tç:.Cg!ú
Projecl No. 16-7-587