HomeMy WebLinkAboutTract 6865 Sump Construction LetterKrun & ASSOCIATES, INC.
GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING
CONSTRUCTION TESTING AND INSPECTIONS
February 16, 2017
Stephen Hair
Gateway Housing, LLC
5301 Office Park Drive, Suite 115
Bakersfield, CA 93309
RE: Completion of Drainage Basin Mitigation
Tract 6865
East Panama Lane & Sparks Street
Bakersfield, California
Dear Mr. Hair:
In accordance with your request, we have prepared this report confirming the completed drainage basin mitigation
at Tract 6865, at the intersection of Panama Lane and Sparks Street, in Bakersfield, California. Krazan &
Associates, Inc. previously completed a Soil Absorption Evaluation report (KA # 022-14205) dated February 2,
2015, for the basin. In our previous report, we recommended that the bottom of the basin be over -excavated to a
depth of 29 feet below original grade, into the underlying sandy soils, and backfill to finish basin grade with clean
sand (less than 5 percent passing the No. 200 sieve). We concluded that implementation of the over -excavation
and backfill with clean sand would be necessary in order for the basin to drain within 7 days or less as designed.
The basin construction was performed during June of 2016, and Krazan & Associates, Inc., was on-site to observe
the completed over -excavation. The excavation had been completed to 29 feet below original grade, completely
exposing the underlying sandy soil across the entire basin bottom. Prior to import of the sand backfill soil, a
sample of the Import fill was collected by Krazan & Associates, Inc. and tested in our laboratory to verify the
amount of material passing the Number 200 sieve. Based on the results of a laboratory sieve analysis, the amount
of material passing the Number 200 sieve was determined to be 3 percent, which is below the maximum allowed
amount of 5 percent. Therefore, we concluded that this Import fill was suitable to use as backfill for the basin.
The basin was subsequently backfilled to the design bottom elevation with the Import fill sand.
Based on our field observations during the basin construction, it is our opinion that the recommendations to allow
for adequate draina(-,e of the basin. as discussed in our _previous report of FebruarG 2, 2015. were adelivatel,
imL)lemented.
In addition to our previous recommendations for mitigation, we maintain that it is imperative that a program of
periodic inspection and maintenance of the basin be implemented, or if already in-place, reviewed and revised as
needed.
2205 Coy Avenue • Bakersfield, California 93307 • (661) 837-9200 • FAX (661) 837-9201
With Offices Serving The Western United States
P:\026\16\128 Tract 6865 Phase 1-3 Building Pads Phase 1 Infrastructure\(2-16-17)_ Basin Mitigation .doc
KA No. 026-16128
Page No. 2
We trust that this report provides the information required at this time. If you have any questions, or if we may be
of further assistance, please do not hesitate to contact our office at (661) 837-9200.
RKP/rp
Respectfully submitted,
KRAZAN & ASSOCIA
Ryan K. Privett, P.E. U,
Senior Engineer 'y
RCE #59372
Krazan & Associates, Inc.
With Offices Serving The Western United States
NO.59372 2
EXP 9/30/2017
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