HomeMy WebLinkAboutObservation of Excavation 10.11.21lftrtffiåffi,TË;i*'=5020 County Road 154
Glenwood Splings, CO 8ló01
phone: (970) 945-7988
fàx: (970) 94s-8454
email : kagienwood@kunrarusa.cotn
www.kumarusa.comAn ãryloyoc Outnecl ConrÞony
Oñìce l¡cations: Denver (HQ), Parke¡ Colorado Springs, Fort Collins, Glenwood Springs, and Surnmit County, Colorado
October 11,2021
GiardHomes
Attn: Roger Giard
l43l Airport Road
Rifle Colorado 81623
Ro eeågi.ard@ ei agltìom es. com
Project No. 20-7-724.4
Subject: Observation of Excavation, Proposed Residence, Golden Stone Drive, Lot M-26,
Roaring Fork Mesa at Aspen Glen, Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on October 8,2021to evaluate the soils exposed for foundation zupport. The
findings of our observations and recommendations for the foundation design are presented in this
report. 'We previously cnnducted a subsoil study for design of foundations at the site and
presented our findings in a report dated January 5,2A21, Project No. 20-7-724. The current
observation was performed according to our professional services agreement with Giard Homes
dated October 6,2021.
Spread footings placed on the natural soils and sized for the recommended allowable bearing
pressure of 1,500 psf were designed for the building support.
At the time of our visit to the site, the foundation excavation had been cut in three levels from
3 to ó feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted primarily of sand (medium dense) and silt (firm) and medium dense to dense, silty sand
and gravel with cobbles generally in the northwest part. The sand and silt soils were slightly
porous and slightly calcareous. Results of swell-consolidation testing performed on samples
taken during our January 2021 study indicate the fine-grained soils have low compressibility
under existing low moisture conditions and light loading and low collapse when wetted under a
constant light surcharge. 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 can be used for support of spread footings designed for the recommended
allowable bearing pressure of 1,500 psf with risk of settlement mainly if the soils are wetted.
The bearing soils are variable fine-grained sand and silt to sandy gravel with cobbles with a risk
ofpost-construction differential settlement. Loose distu¡bed soils should be moistened and
compacted or removed in the footing areas to expose the undisturbed natural soils. The bearing
Giard Homes
October ll,202l
Page2
soils should be protected from ùost and concrete should not be placed on frozen soils. Other
recommendations presented in our previous report which are applicable should also be observed.
The recommendations submitted in this letter a¡e based on our observation of the soils exposed
within the foundation excavation and the previous substrrface 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 aprofessional in
this special field of practice should be consulted.
If you have any questions or need further assistance, please call our office.
Sincereþ,
Kumar & Associates,
Steven L. Pawlak,
SLPlkac
Kumar & Associates, lnc.tl Project No. 20-7-724.A
Roqer Giard
Sent:
To:
Cc:
From:Jake Timmons <jake@riverstonesc.com>
Tuesday, October 12,2021 4:24 PM
Nick Weaver; Wayland Weatherred
Roger Giard
RE: Excavation Observation, Lot M-26 Roaring Fork Mesa at Aspen Glen, Garfield
County, CO
Thanks Nick,
No issues here. The report just confirms the original assumptions of the geotechnical report hold
Our design conforms to that report so I take no issues or exceptions.
Good to proceed.
Thanks!
Jake Timmons, P.E.
PRINCIPAI I StrucÌural Engineering
Riverstone Structural Concepts
O 208 343 2092 {Ext.9sB4) | D 208 9s4 8sB4
From: Nick Weaver <nweaver@triad partners. net>
Sent: Tuesday, October 12,2021 4:21PM
To: Jake Timmons <jake@riverstonesc.com>; Wayland Weatherred <wayland@ka-designworks.com>
Cc: Roger Giard <Roger.giard@giardhomes.com>
Subiect: Fwd: Excavation Observat¡on, Lot M-26 Roaring Fork Mesa at Aspen Glen, Garfield County, CO
Jake,
Attached is the observation excavation letter from our soils test after excavation. Please review and comment/approve.
Thank you,
Nick
Begin forurarded message
From: Roger G iard <roger.qia rd @giard ho mes.com>
Date: October L2,2O2Lat 4:L5:58 PM MDT
To: Nick Weaver <nweaver@triadpartners.net>, Joseph Carroll <icarroll@triadpartners.net>
Subject: FW: Excavation Observation, Lot M-26 Roaring Fork Mesa at Aspen Glen, Garfield County, CO
Nick and Joseph,
Here is the formal Excavation Observation letter from Kumar for your records. Please forward to your
architect and structural engineer for review/ approvals.
Subject:
1
Thanks,
Roger Giard
Giard Homes lnc
1431Airport Rd.
Rifle, Co 81650
Cell (970) 230-1s36
Office l970l62s-2347
Fax (970) 625-3607
Roger.gia rd (ôeia rd homes.co m
www.giardhomes.com
From: Kathy Crisler <kcrisler@kumarusa.com>
Sent: Tuesday, October 12,2O2L 4:05 PM
To: Roger Giard <roger.gia rd @giardhomes.com>
Subject: Excavation Observation, Lot M-26 Roaring Fork Mesa at Aspen Glen, Garfield County, CO
Please see attached Report. lf you have any questions, please call us.
Thank you,
Kathy
Kolhy Crisler
Adminiskqtive Assislonl
5020 County Rood 154
Glenwood Springs, Colorodo Bl60l
P: (970) ?4s-7988
E: kcrisler@kumoruso.com
www.kumoruso.com
Denver (HQ) | Porker I Colorodo Sprlngs I Forl Collins I Glenwood Springs I Summil County
Geotechnlcql Engineering I Engineeilng Geology I Conslruclion Moteriols lestlng I Envlronmenlol Services
Confídentiolily Nolice: The informoiion ironsmílted is intended only for the person or entiiy to which il is oddressed ond moy
conioin confidenTiol ond/or privileged moierìol. Any review, copying, lrqnsmission, disclosure, disiribution, disseminolion or other
use of, or toking of ony oction in relionce upon lhis informoiion by person or enliiies olher lhon lhe inlended recipient is
prohibiled. lf you received this in enor, pleose contoci lhe sender ond delele the maieriol from ony computer.
2