HomeMy WebLinkAboutReview of Proposed Hillside Grading Plan 10.25.2019K+A
Kam 8Associates, Am*
Geoter u ical and Materials Engineers
and Environmental Scientists
An Employee Owned Company
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com
Office Locations:
October 25, 2019
Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
Rudd Construction
Attn: Eric Rudd
0132 Park Avenue
Basalt, Colorado 81621
eri e(4),ruddi:olistruction. com
Subject:
Gentlemen:
RECEIVED
.1d..7aH 202. _i
GARFIELD COUNTY
COMMUNITY DEVELOPMENT
e
30%44*
WMMAYI�NIq�
1989-x6.fA61
�
Project No. 17-7-858.A
Review of Proposed Hillside Grading Plan Behind Building Q, Cattle Creek
Center, Garfield County, Colorado
As requested by Tim Beck, we have reviewed the proposed grading plan behind Building Q for
geotechnical issues. We previously conducted a subsoil study for design of foundations at the
site and presented our findings in a report dated February 15, 2018, Project No. 17-7-858.
Building Q site is the south building closest to the hillside of the proposed 6 buildings. The
uphill, east wall of Building Q will retain earth to a depth of about 10 feet. The backfill surface
will be sloped back at 10% for 5 feet to a stacked boulder wall (or equivalent) up to 4 feet high
below the hillside. The hillside will be graded at 1'/2 horizontal to 1 vertical to the catch point of
around 12 feet above the top of boulder wall. The hillside mainly consists of dry Eagle Valley
Evaporite with minor colluvial soil cover.
Based on our review, the proposed construction is acceptable from a geotechnical viewpoint.
The building wall backfill can consist of the onsite soils or imported structural material
compacted to at least 95% of standard Proctor density at near optimum moisture content. The
backfill surface swale should have a minimum 2% cross slope in a horseshoe shape around the
building to daylight. 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.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, toe.
Steven L. Pawlak, P.E.
SLP/kac
cc: Zancanella & Associ
(tbeck(cr,za-engineering.com)