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~CI# OF SAN BERNARDIC>> - REQuI:)yOpOR9COUNCIL,Ab:);;N
I'
From: Roger G. Hardgrave
Dept: Public Works/Engineering
Date: 9-16-86
REC'O. _ Alffflt7r.: Report on Resul ts of Soil Tests --
. OM.te for Construction of New Fire
1986 Sf? '7 MIlO: Station in Tri-City Corporate Complex
!1 27
Synopsis of Previous Council action:
5-19-86 --- Resolution No. 86-185 adopted authorizing execution of an agreement
with Kurt Meyer Partners relating to providing architectural services
on construction of new fire station in Tri-City Corporate Complex.
Recommended moti,on:
That the report on the preliminary results of the geotechnical
investigation by Geofon, Inc. on the proposed site for con-
struction of a new fire station in the Tri-City Corporate
Complex, be accepted and filed.
cc: Ray Schweitzer
Glenda Saul
Craig Graves
G. Newcombe
ffi,!fTh-
Supporting data attached:
Staff Report
Ward:
5025
1
Contact person:
Roger G. Hardgrave
Phone:
FUNDING REQUIREMENTS:
Amount:
N/A
Source:
Finance:
Council Notes:
75.0262
Agenda Item No,
s..z.
I CIT9 OF SAN BI!RNARDIO>> - REQUIOT FOR COUNCIL ACQoN
, .
STAFF REPORT
Page 1 of 2
An estimate of the additional costs that could be incurred for construc-
tion of the new fire station in the Tri-City area, due to the existence of an
old land fill, was presented in a letter, dated 7-9-86, from Keith McClure,
Architect. This estimate was in the amount of $190,000, but was very preliminary
due to the absence of any definitive information on the depth, composition and
compaction of the buried refuse.
Geofon, Inc. was engaged to perform a geotechnical investigation of the
site, in order to obtain sufficient data upon which to base an estimate. Data
secured by this investigation was transmitted by telephone to this office on
9-16-86, by Mr. Byron Konstantinidis, Vice-President of Geofon, Inc.
In general, this investigation revealed that the conditions were more
favorable than anticipated. Different alternatives were reviewed by Geofon that
would provide sufficient support to prevent structural distress in the building
and provide a good base for the pavement. Some localized settlement can still
be expected in the pavement, with additional m~intenance required over the lon~
term,
All alternatives considered ,removing the top 3 feet of soil, and dis-
posing of the small amounts of refuse encountered on site. This process was
selected since hauling refuse to an operating land fill is prohibitively ex-
pensive.
The least expensive alternative consisted of removing the soil to a
depth of 9 feet under the building pad, disposing of refuse encountered on site,
and providing a stiffened slab foundation. This arrangement will tolerate some
settlement, without distressing the building. The estimated cost for this
alternative is $78,000 - $103,000. Additional geotechnical investigation by
Geofon during construction would'cost $10,000.
If the building site could be shifted to the west line of Lot 31, of
Tract No. 12,034, there would be a lower potential for settlement, and a savings
of up to $10,000 could be realized. An agreement has been reached with Tri-City
Corporate Center that the joint driveway to the fire station and remainder of
Lot 31, would be adjacent to the west lot line. Approval from Tri-City would be
needed to shift the station site and move the joint driveway to the east side
of the structure.
, In addition to the structural considerations, there is also the require-
ment for landfill gas protection facilities. As a minimum, a membrane and
passive ventilation system is required for structures built on old landfills,
A preliminary estimate of cost was provided by Galen S. Petoyan, of
SCS Engineers, by letter dated 8-1-86, This letter states that a membrane and
ventilation system typically costs from $1.50 to $3.50 per square foot of
building. Design fees for SCS Engineers would run from $2,000 to $4,000. For
our proposed 5,000 square foot building, the membrane and ventilation system
will cost from $7,500 to $17,500.
75.0264
'CI-N OF SAN BERNARDI()) - REQUIOT FOR COUNCIL ACOON <"
STAFF REPORT
Page 2 of 2
Listed below are the estimated cost ranges for special treatment due
to the old landfill.
Recompacting & Stiffened Slab
Geotechnical Investigation by Geofon
Membrane & Ventilation System
Design Fees by SCS Engineers
$ 78,000
10 ,000
7,500
2,000
$103,000
10,000
17 ,500
4,000
TOTALS
$ 97,500
$134,500
An amount of $70,000 was included in the project budget to cover the
additional costs due to the landfill.
The final report from Geofon will be available in about a week.
75-0264