HomeMy WebLinkAbout5.2. .... .. - --------
ITEM 5.2
TOWN OF LOS ALTOS HILLS February 7, 2013
Staff Report to the Planning Commission
SUBJECT: SITE DEVELOPMENT PERMIT FOR A 2,366 SQUARE FOOT BUNKER:
LANDS OF JJP REALTY ENTERPRISES, LLC: 11481 MAGDALENA ROAD;
FILE # 218-1 1-ZP-SD-GD
FROM: Nicole Horvitz, Assistant Planng��W
APPROVED: Debbie Pedro, AICP, Planning Director
RECOMMENDATION- That the Planning Conirmission:
Approve the: requested' 'Site Development Permit for the• proposed bunker. 4ubj ect to -the
conditions of approval 'in Attachment T.
............. - ----- ... .... . .......
BACKGROUND
The subject property is located:'on thd'-.fioiiff. "side hof Magdalena Road.;_ `The': s&T6findifi9)&6s
include single family r6sidenceg to'the north, south, west, and across Magdalena Road to -the east.
On March 8, 2000, the Planning.. Commigsion- approved a: 12,211 o square foot new residence with
a '5,101 square foot basement and a tennis court on this 6.0 acre -T`l -property. Other Site
Development Permits for this property include a landscape screening plan approved on March
19, 2002 (SDP# 15-02-ZP-SD). A. 3,353 square foot swimming pool and decking d o
approved
September 2, 2008 (SDP# 13 8-08-ZP-SD), and a 7,065 square foot tennis * court was. approve . d .- on
September 10, 2009 (SDP # 60-09-ZP-SD-GD). The applicant did not build the tennis court and
the approval :has -since expired. On September 20,,,2011 an application was. submitted for a
bunker.
F:.
CODE REQUIREMENTS
Per. Section 10-1.202 (Basements) -of the Zoning Ordinance this application
fon-ft bunker has
been forwarded to the Planning Commission for review.
DISCUSSION
Site Data:
Gross Lot Area:
6.0 Acres
Net Lot Area:
3.02 acres
Average Slope:
19.7%
Lot Unit Factor:
2.39
Staff Report to the Planning Commission
Lands of JJP Realty
1148.1 Magdalena Road
February 7, 2013
Page 2 of 8
Floor Area and Development. Area:
Area (sq ft) Maximum Existing Proposed Increase Remaining
Development 27,235 23,185 25,551 2,366 1,684 -
Floor 13,209 12,211 13,077 866 132
(Basement 5,101) (Bunker 1,500)
The 2,366 square foot bunker is proposed at the rear (east) of the residence. Pursuant to Los
Altos Hills Municipal Code Section 10-1.202, 1,500 square feet of the proposed bunker is
exempt from floor area calculations.
"Basements, including cellars and bunkers, which are not located within the
footprint of the building above, may be permitted by the Planning Commission
when it finds that such structures do not encroach in setbacks, are a minimum of
eighteen (18) inches below natural grade, are wholly underground except for
required exiting, lighting and ventilation and are counted asdevelopment area
except -when -placed -under -a, surface- already -counted as -development -area. -Bunker .
area exceeding one thousand five hundred (1,500) square feet shall be counted as
floor area. "
546 square feet of the bunker has been included in the floor area calculations. 320 square feet of
skylights proposed in the design of the bunker to allow for natural light and to allow items to be
lowered into the bunker. Since the skylight areas are not 18" below grade, this area has been
included in the floor area calculations. The entire area (2,366 square feet) is included in the
development. area calculations. Access to the bunker will be through the existing basement.
Grading and Drainage
Total grading quantities for this project include 1,500 cubic yards of cut for the bunker. The total
vertical cut for the bunker is up to 22'6". The Engineering Department has reviewed the
proposed grading plan and concluded that it is in conformance with the Town's Grading Policy.
Water runoff generated from the new development will be collected in a 4" subdrain pipe. The
runoff will then be carried to a new. energy dissipater north of the bunker.
Pursuant to Section 10-2.503, Drainage Facilities Standards, of the Municipal Code, the
Engineering Department has reviewed and determined that the proposed drainage design
complies with Town requirements. The Engineering Department will review and approve the
final drainage plan prior to acceptance of plans for building plan check. Final "as -built" grading
and drainage will be inspected by the Engineering Department and any deficiencies will be
required to be corrected prior to final inspection.
Staff Report to the Planning Commission
Lands of JJP Realty
11481 Magdalena Road
February 7, 2013
Page 3 of 8
Fire Department Review
The Santa Clara County Fire Department has reviewed the proposal and is requiring a sprinkler -
system throughout all portions of the bunker, an onsite hydrant, a fire access driveway, and fire_
truck turnaround. (Attachment 2)
Geotechnical Review
The Town's geotechnical consultant Cotton, Shires & Associates, Inc., has reviewed the soil and
foundation report prepared by Ting and Associates dated May 8, 2012 and recommends approval
of the permit based on conditions 7 a & b. (Attachment 3)
Committee Review
The Environmental Design and Protection Committee commented that there are no obvious
-environmen =issues.(Attachment-4)_-
Neighbor Concerns
To date, staff has not received any neighbor comments.
CEQA STATUS
The project is categorically exempt under CEQA per Section 15303 (e)
ATTACHMENTS
1. Recommended Conditions of Approval
2. Recommendations from Santa Clara County Fire Department dated September 28, 2012
3. Recommendations from Cotton, Shires, and Associates dated October 9, 2012
4. Comments from Environmental Design and Protection Committee dated October 17, 2011
5. Site Development plans
Staff Report to the Planning Commission ATTACHMENT 1
Lands of JJP Realty
11481 Magdalena Road
February 7; 2013
Page 4 of 8
ATTACHMENT 1
RECOMMENDED CONDITIONS OF APPROVAL FOR
SITE DEVELOPMENT PERMIT FOR A BUNKER
LANDS OF JJP REALTY, 11.481 MAGDALENA ROAD
File # 218-11=ZP-SD-GD
PLANNING DEPARTMENT:
1. No other modifications to the approved plans are allowed except as otherwise first reviewed
and approved by the Planning Director or the Planning Commission, depending on'the scope
of the changes.
2. All existing Blue Gum
T. globulus), Pink Ironbark (E. sideroxylon rosea), River Red Gum
-(E. -camaldulensis}; Swamp-Gum-(E:-rudis); -Honey-Gum- (E.-melliodora); or Manna -Gum -(E:
viminalis eucalyptus trees on the property located within 150' of any structures or roadways
shall be removed prior to final -inspection of the residence:. Removal of eucalyptus trees
shall take place between the beginning of August and the end of.! to avoid disturbance
of nesting birds protected under the Federal Migratory Bird Treaty Act (MBTA) and California
Department ,of Fish and Game Code. Section 3500 et seq unless a nesting. bird survey is first
conducted and there is a determination that there are no active _nests w thm the tree.
3. Prior to beginning any grading operation, all significant trees, particularly the heritage oak
trees, are to be fenced at the drip line. The fencing shall be -of a material"and'structure (chain
link) to clearly delineate the drip line. Town staff must inspect the fencing.and the trees,to be
fenced prior to commencement of grading. The property -owner shall call. for said -inspection
at least three days in advance of the inspection. The fencing must remain throughout the
course of construction. No storage of equipment, vehicles or debris shall be. allowed within
the drip lines of these trees. Existing perimeter plantings ' shall be fenced andretained
throughout the entire construction period.'
4. Prior to requesting the final inspection, a registered. civil engineer. or licensed land
surveyor shall certify in writing. and state that "the location of the new bunker is less -than 40'
from the front property line and 30 " from the side and rear property lines." The elevation of
the new bunker shall be similarly, certified in_ writing to state that "the elevation of the new
bunker matches the elevation and location shown 'on the `Site Development plan." The
applicant shall submit the stamped and signed letters) to the ' Planning Department
prior to requesting a final inspection and prior to final inspection.
5. Fencing is approved as shown on the plans. Any new fencing or gates.shall require review
and approval by.the Planning Department prior to installation.
Staff Report to the Planning Commission
Lands of JJP Realty
11481 Magdalena Road
February 7, 2013
Page 5 of 8
6. No new lighting is approved. No lighting may be placed within setbacks except two entry or
driveway lights. Any additional outdoor lighting shall be approved by the Planning
Department prior to installation.
ENGINEERING DEPARTMENT:
7. As recommended by Cotton, Shires & Associates, Inc., in their report dated October 9, 2012,
the applicant shall comply with.the following:
a. Geotechnical Plan Review — The applicant's geotechnicalconsultant shall review
and approve all. geotechnical aspects of the project building and grading plans (i.e.,
site preparation and grading, .site drainage improvements and design parameters for
foundations, retaining walls, tennis court and driveway) to ensure that their
recommendations have been properly incorporated.. Geotechnical aspects of project
drainage discharge should be specifically evaluated.
The results . of theplan review should be summarized by the geotechnical consultant
in a letter and submitted to ' the Town Engineer for review prior to acceptance of
plans for Building plan check
b. Geotechnical Construction Inspection — The' geotechnical consultant shall inspect,
test (as needed), and approve all geotechnical aspects of the project construction. The
inspections should include; but not necessarily be limited to: site preparation and
grading, site surface and subsurface drainage improvements, and excavations for
foundations and retaining walls and pool prior to the placement of steel and concrete.
The consultant should..complete 'an inspection of final site drainage improvements
for conformance with geotechnical standards.
The results of these inspections and the as -built conditions of the project shall be
described by the geotechnical consultant in a letter, and submitted to the Town.
Engineer for review prior to final inspection.
For further details on the above geotechnical requirements, please refer to the letter from
Cotton, Shires & Associates, Inc., dated October 9, 2012
8. Two sets of a final grading and drainage plan shall be submitted for review and approval by
the .Engineering Department prior to acceptance of plans for building plan check Final
---grading-and drainage -shall -be -inspected -by -the -Engineering -Department -and any -deficiencies--- -_
corrected to the satisfaction of the Engineering Department prior to final inspection. A letter
shall be submitted from the project engineer stating that the site grading and drainage
improvements were installed as shown on the approved plans prior to final inspection.
Staff Report to the Planning Commission
Lands of JJP Realty
11481 Magdalena Road
February 7, 2013
Page 6 of 8
9. Any, and all, changes to the approved grading and drainage plan shall first be approved by the
Town Engineering Department. No grading shall take place during. the grading moratorium
(October 1 to April 30) except with prior approval from the City Engineer. No grading shall
take place within ten feet of any property line.
10. Two copies of an erosion and sediment control plan: shall be . submitted for review and
approval by the Engineering_ Department priorto acceptance of plans for building plan
check.. The contractor and the property owner shall comply with all appropriate requirements
of the Town's NPDES permit relative to grading and erosion/sediment control. All areas on
the site that have the native soil disturbed .shall . be protected, -for erosion control during the
rainy season and shall be replanted prior to .final inspection.
11. The property owner shall inform the Town of any damage and shall repair any damage caused
by the- construction of the project to pathways, private. driveways, and public :and. private
roadways, prior to final inspection and release of occupancy permits and shall provide the
_
__. T-own-_vMth_ photographs =of _the-. existing _conditions -:of -_the_ -roadways -and :.pathways= prior.:.::to
acceptance of plans for building plan check
12. Two copies of a grading and construction operation plan shall be: submitted by the property
owner for review and approval- by the City Engineer• and Planning- Director prior to
acceptance of.- plans for building plan check The grading/.construction operation plan shall
address track traffic.issues regarding dust -noise, and,vehicular and pedestrian traffic safety
on Magdalena Road and surrounding roadways; storage of construction materials; placement
of sanitary facilities; parking for construction vehicles; and parking for construction
-personnel. A debris box (trash : dumpster),: shall be. placed on site for collection of
construction debris. Arrangements must be made with the GreenWaste Recovery, Inc. for
the debris box, since they! have a franchise with the Town and no other- hauler is allowed
within the Town limits.
FIRE DEPARTMENT:
13. An automatic residential fire sprinkler system approved by -:the Santa Clara County Fire
Department shall be ° included in all- portions of the building. Three sets of plans prepared by a
sprinkler contractor shall be submitted to the Santa Clara County Fire Department (14700
Winchester Blvd., Los Gatos, CA. 95032)= for review and .approval. The sprinklers -shall- be
inspected and approved by the Fire Department, prior to final inspection and occupancy of the
structure.
14. The applicant shall provide an approved fire department engine driveway turnaround with a
minimum radius of 36 feet outside and 23 feet inside.
Staff Report to the Planning Commission
Lands of JJP Realty
11481 Magdalena Road
February 7, 2013
Page 7 of 8
15. The applicant shall.provide an access driveway with a paved all weather surface, a minimum
unobstructed width of 14', vertical clearance of 13'6", minimum circulating turning radius of
36' outside and 23' inside, and a maximum slope of 15%.
16. Provide one on site fire hydrant at locations to be determined by the Fire Department.
Maximum hydrant spacing -shall be 500 feet, with a minimum acceptable flow of 1,000 GPM
at 20 PSI residual pressure. Prior to design, the project civil engineer shall meet with the fire
department water supply officer to jointly. spot the required fire hydrant locations.
17. -Installation of private fire .service mains and/or fire hydrants shall conform to National Fire
Protection Association standards and Fire Department Standard details. A separate
installation permit from the Fire Department is required.
18. Installations of required fire services) and- fire hydrant(s) shall be tested and accepted by the
Fire Department prior to the start of framing or delivery of bulk combustible materials.
Building -permit-.issuance: may.. be. -withheld. .until _required -installations -are completed; --tested,
and accepted.
19. Required access roads, up though first lift of asphalt shall be installed and accepted by the
Fire - Department prior to the start of combustible construction. During construction,
:emergency access roads shall be maintained clear and unimpeded. Building permit issuance
may be withheld until installations are completed. Temporary access roads may be approved
on a case by case basis.
CONDITION NUMBERS 7a, 8,10,11, and 12 SHALL BE COMPLETED AND SIGNED OFF
BY THE PLANNING DEPARTMENT AND THE ENGINEERING DEPARTMENT PRIOR
TO ACCEPTANCE OF CONSTRUCTION- PLANS FOR PLAN CHECK BY THE
BUILDING DEPARTMENT.
Project approval may be appealed if done so in writing within 22 days of the date of this notice.
The building permit cannot be issued until the appeal period has lapsed. The applicant may
submit construction plans to the Building Department provided the applicant has completed all
conditions of approval required prior to acceptance of plans for building plan check. -
Please refer to the Conditions of Project Approval set forth herein. If you believe that these
Conditions impose any. fees; dedications,_ reservation or other exactions under the California
Government Code Section 66000, you are hereby notified that these Conditions constitute written
notice -of -a-statement-of -the--amount-of-such-fees;--and/or-a--description-of--the-dedications,-
reservations, and other exactions. You are hereby .furthernotified that the 90 -day approval
period in which you may protest such fees, dedications, reservations, and other exactions,
pursuant to Government Code Section 66020(a), has begun. If you fail to file a protest within
this 90 -day period complying with all of the requirements of Section 66020, you will be legally
bared from later challenging such exactions.
Staff Report to the Planning Commission
Lands of JJP Realty
11481 Magdalena Road
February 7, 2013
Page 8 of 8
Upon completion of the construction, a final inspection shall be required to be set with the
Planning and Engineering Departments two weeks prior to final building inspection approval.
NOTE: The Site Development permit is valid for one year from the approval date (until February
7, 2014). All required building permits must be obtained within that year and work on items not
requiring a building permit shall be commenced within one year and completed within two years.
Actaeo r".! ATTACHMENT 2
FIRE DEPARTMENT
FIRE A SANTA.- CLARA COUNTY
14700 Winchester Blvd., Los Gatos,. CA 95032-1818
`°`° (408) 378-4010 • (408) 378-9342 (fax) • www.scdd.org
PLAN
REVIEW '. -.12 3189
BLDG'
DEVELOPMENTAL REVIEW COMMENTS PERMIT No.
posed construction of tennis court and 6,555 square foot- underground bunker directly ben
:us court. The bunker will provide enclosed vehicular storage. and access for persons.
!Comment #1: See our Plan Log #09-0769 for detailed conditions
`Comment #2: All conditions required -by this Department are shown on current edition -of plans.
Plans approved. OK. to issue Building Permit.-
-
i
i
OCi 0 4 201
City. PLANS SPECS NEW RMOL AS
LAH N 11 ® 13
OCCUPANCY
SFR
CONST. TYPE
V -B
APPOcarttNww
Lea & Braze Engineering Inc :-09/28/201
DATE
PAGE
1 OF 1
SECIFLOOR
see plans
AREA
see plans
LOAD
PROJECT DESCRIPTION
Residential Development
PROJECT TYPE OR SYSTEM
Design Review
NAME OF PROJECT
SFR
LOCATION
11481 Magdalena Rd Los Altos Hills
TABULAR FIRE FLOW
2250
REDUCTION FOR FIRE SPRINKLERS
I REQUIRED FIRE FLOW @ 20 PSI
1500
BY
Hazdin& Doug
1 5070
urganizea as the aanta Uara C;ounty (ventral Fire Protection District
Seeing Santa Clara County_ and the communities of Carrlpbefl, Cupertino, Los Altos,
Las Altos Hills. Los Gatos_ Monte Serenri_ Morann Hill m,ri Sn mmnn
FIRE DEPARTMENT APR 0 7 2009
SANTA CLAVA COUNTY
14700 Winchester Blvd., Los Gatos, CA 95032-181TPW'"LOS ALTOS HILLS
(408) 378-4010 • (408) 378-9342 (fax) • www.sccfd..org I,ter„afion* a,=e&ted
Agency
PLAN REVS w NUMBER 0 9 0769
DEVELOPMENT REVIEW COMMENTS
COOEMEC.
CFC Sec.
903.2, as
adopted
and
amended
by LAHMC
SHEET I NO.I REQUIREMENT
BLDG PERMIT NUMBER
FILENUMBER 60-09-ZP-SD-GD
>osed construction of tennis court and 6,555 square foot underground bunker
_dy beneath tennis court. The bunker will provide enclosed vehicular storage
access for persons.
Review of this Developmental proposal is limited to acceptability of site access
and water supply as they pertain to fire department operations, and shall not be
construed as a substitute for formal plan review to determine compliance with
adopted model codes. Prior to performing any work the applicant shall make
application to, and receive from, the Building Department all applicable
cnnciTli�*fi[1nf1PTr11.7f.S_
Fire Flow: The fire flow for this project is 1,500 gpm at 20 psi residual
The adjusted fire flow is available from area water mains and fire
I which are spaced at the required spacing.
Fire Sprinklers Required Approved automatic sprinklers are required in all new
and existing modified buildings when gross floor area exceeds 3,600 square feet or
that are 3 or; more stories in height. Exception:One-time . additions to existing
buildings made after 01 / Ol / 2008 that do not exceed 500 gross square feet. An
automatic sprinkler shall be provided in all new structures located in the
designated Wildland-Urban Interface area. A State of California licensed (C-16) Fire
Protection Contractor shall submit plans, calculations, a completed permit
application and appropriate fees to this department for review and approval prior
to begin=g their work
City PLANS SPECS NEN RMDL AS
OCCUPANCY
CONST. TYPE
JAPPIkantNam
DATE
PAGE
--®
V -B
PLANNING
2009
4/6/F-
1 OF 3
L -AH_..__--® ._Q ----❑-..---R-3__
-_ ._ --
---WHISLER- -
--
_
SECJFLOOR
AREA
LOAD
OESCRIPTION
BY
1 floor below grade
6555 sf
Residential Development
Harding, Doug
NAME OF PROJECT
LOCATION
SFR
11481 Magdalena Rd
Organized as the Santa Clara County Central Fire Protection District
Serning Santa Clara County and the communities of Campbell, Cupertino, Los Altos,
Los Altos Hills, Los Gatos, Monte Sereno, Morgan Hill, and Saratoga
IECEIVED
FIRE DEPARTMENT -
SANTA CLARA COUNTY APP 0 7 2009
a�
FIRE • : - . .
14700 Winchester Blvd., Los Gatos, CA 95032-18 OF LOS ALTOS Hlli
��• (408) 378-4010 • (408) 378-9342 (fax) • www.scdd.org I, ,A=e&ted
As-cy
PLAN REvmw NvmBER 09 0769
BLDG PERMIT NUMBER
DEVELOPMENT REVIEW COMMENTS FILE NUMBER 60-0s-zP-So-G`o
IOE/SEC. SHEET NO. REOumEmBrr
:Set. 3 Private Fire Hydrant(s) Required: Provide 1 private on-site fire hydrant(s)
!PdFix g installed per NFPA Std. #24, at location(s) to be determined by the Fire
C Department. Maximum hydrant spacing shall be 500 feet, with a minimum
acceptable flow of 1,000'GPM at20si residual pressure. Prior to -design, the
project civil engineer shall meet with the fire department water supply officer to
jointly spot the required fire hydrant locations.
:Set 4 Private On Site Fire Service Mains and/or Hydrants: Installation of private fire
.3, per service mains and/ or fire hydrants shall conform to National Fire Protection
zencux B - -- ---.- .--- - — _ - - — p -
e Assoeration-(NFPA}StandAfci #24,-and==FireDe artm- ent-Standatd=Details-.and
Specification W-2: A Separate installation permit from"this cittaftment is
required. (Note: if the fire hydrant is to be dedicated back to the California
Water Service Company, installation -will be per that agency).
Set. 501 5 Timing -of Required Water Snpply Installations: Installations of required fire
service(s) and fire hydrant(s) shall be tested and accepted by the Fire Department,
prior to the start of framing or delivery of bulk combustible materials. Building
permIt issuance maybe withheld until required installations are completed, tested,
and accepted.
NOTE: Some requirements listed herein also appear in our Review #99-3485.
Future editions of the plans must identify the location of any existing public or
private hydrants serving this property within 600 feet of the property lines on
Magdalena. and private water storage tanks, if any.
C Sec. 503 6 Fire Apparatus (Engine)Access Driveway Required: Provide an access driveway
with a paved all weather surface, a minimum unobstructed width of XX feet,
vertical clearance of 13 feet 6 inches, minimum circulating turning radius of 36 feet
outside and 23 feet inside, and a maximum slope of 15%. Installations shall
Cdy PLANS SPECS NEWRI®L AS OCCUPANCY CONST. TYPE ApplfeamNaisa DATE T:2
E
�H ® ❑ ® El E3 R-3 V -B WHISLER LAND PLANNING 4/6/200cF 3
;JFLOOR AREA LOAD DESCRIPTION BY -
loor below grade 6555 sf Residential Development Harding, Doug
WE OF PROJECT LOCATION
SFR 11481 Magdalena Rd
Organized as the Santa Clara County Central Fire Protection District
Serving Santa Clam County and the communities of Campbell, Cupertino, Los Altos,
f .,c d Ifnc I-lillc f nc /',nfnc Adnnlo Soronn Mnmm� Full mv4.�'
nmlrvrn
G�� C
ew�srs�n�
FIRE DEPARTMENT RECENED
SANTA CLARA COUNTY
14700 Winchester Blvd., Los Gatos, CA 95032-1818 2009 .
(408) 378-4010 • (408) 378-9342 (fax) s www.sccfd.org OF LOS ALTOS i�1 ..5 �"`g" ff dy A...aeea
Asumv
PLAN REVIes NUMBER O 9 0769
DEVELOPMENT REVIEW COMMENTS
COOElSEC. I SHEET I NO.
ZFC Sec 5031
::FC Sec
REQUIREMENT
BLDG PERIMT NUMBER
FlLENumsER 60-09-ZP-S D -G D
conform to Fire Department Standard Details and Specifications sheet D-1.
!partment (Engine) Driveway Turn -around Required: Provide an
'ed fire department engine driveway turnaround with a minimum radius of
outside and 23 feet inside. Installations shall conform with Fire Department
rd Details and Specifications D-1.
Tinunof ReuirettR��clwa Installations: Req, uiied, access roads, up through
first lift of asphalt, shall be installed and..accepted by the Fire Department prior, to
the start of combustible construction. During construction, emergency access roads
shall be maintained clear and unimpeded. Note that building permit issuance may
be withheld until installations are completed. Temporaryaccess roads may be
approved on a case by case basis.
To prevent plan review and inspection delays, the above noted Developmental
Review Conditions shall be addressed as "notes" on all pending and future plan
submittals and any referenced diagrams to be reproduced onto the future plan
LAH---.--®--❑---®.----� --❑---R-3._._....—VrB_.__-.______.._WHISLER LAND PLANNING.- ----4/6/2009---3---oF -3----
SECJ LOOR AREA LOAD DESCRIPTION By
1 floor below grade 6555 sf Residential Development Harding, Doug
NAME OF PROJECT LOCATION
SFR 11481 Magdalena Rd
Organized as the Santa Clara County Central Fire Protection District
Seruing Santa ClaraCounty and the communities of Campbell, Cupertino, Los Altos,
Ltn-c Altos Huls Los Cues- Mnnfa_ .SPrann Wrenn Nil{ and .q r mon
1 ( " ATTACBWNT 3
COTTON, SHIRES AND ASSOCIATES, INC.
rA61000NSULTING ENGINEERS AND GEOLOGISTS 041CT 12 2012
TWOR0,IMS HILLS
L0079B
TO: Nicole Horvitz
Planning Department
TOWN OF LOS ALTOS HILLS
26379 Fremont Road
Los Altos Hills, California 94022
SUBJECT: Geotechnical Peer Review
RE: Pan Underground Collections Building
11481 Magdalena Road
At your request, we have completed' a geotechnical peer review of, the site
development and grading applications for the underground collections building using:
• Proposeet Underground Collections (letter -report) prepared by
Wayne Ting &Associates, dated May 8, 2012;
• Civil Plans, Grading, Drainage, Erosion Control and Details:. (8
sheets, various scales) prepared by- Lea &. Braze Engineering Inc,
dated September 24,.2012;
• Site .and Floor Plans and Sections (3 sheets, various scales)
prepared by Whistler Land -Planning, dated September 24,-2012;
• Geotechnical Investigation (report) prepared by Ting and
Associates, dated November 6;1999; and
• Fault Investigation — Proposed Residence (report) prepared. by
Steven F. Connelly, CEG, dated November 8; 1999.,
In addition, we'have reviewed pertinent data from our office files (L3409).
DISCUSSION
- The applicant proposes to construct a subsurface collections building with an
access tunnel connected ..to -the.. basement of the existing residence. The proposed
structure is located immediately east -of the northeastern corner of the existing
residence. Proposed earthwork quantities have been estimated at 1,500 cubic yards of
cut and 590 cubic yards of fill. We understand that the majority of proposed fill
Northern California Office Central California Office Southern California Office
330 Village lane 6417 Dogtown Road 550 St. Charles Drive, Suite 108
Los Gatos, CA 95030-7218 San Andreas, CA 95249-9640 Thousand Oaks, CA 91360-3995
(408) 354-5542 • Fax (408) 3541852 (209) 736-4252 • Fax (209) 736-1212 (805) 497-7999 • Fax (805) 497-7933
Nicole Horvitz October 9, 2012
Page 2 L0079B
placement is located on a moderately steep slope located approximately 100 feet
northwest of the existing residence. We understand that the project .includes
construction of a retaining wall upslope of a site generator and also along a spur access
road extending from the upper driveway.
SITE CONDITIONS
The property is underlain, at depth, by bedrock materials of the Monterey
Formation and Franciscan Complex which are juxtaposed by the Berrocal fault that
crosses through the property. Based on a previous site fault investigation, the Berrocal
fault is located over 100 feet west of the proposed collections building. Slopes at the
proposed building site are gentle and characterized by the crest of knoll. Steep (50
percent inclination) slopes are present north of the proposed building site in the vicinity
of a proposed drainage dissipater.
CONCLUSIONS AND RECOMMENDED ACTION
Proposed site construction is constrained by potentially expansive earth
materials and violent seismic ground shaking. The Project Geotechnical Consultant has
presented project. design recommendations that are in general conformance with
prevailing geotechnical standards.. We recommended that the Project Geotechnical
Consultant critically review proposed drainage plans and the proposed location for
drainage discharge. Typically, discharging water at the base of steep slopes reduce
erosion,, compared to discharge on steep slopes. We recommend geotechnical. approval
of permit applications for project construction with, the following conditions:
1. •.Geotechnical Plan Review — The applicant's geotechnical
consultant shall review and approve all geotechnical aspects of
the project building and grading plans (i.e., site preparation and
grading, site drainage improvements and design parameters for
foundations and retaining walls) to ensure that their
recommendations have been properly incorporated.
Geotechnical aspects of project drainage discharge should be
specifically evaluated.
The results of the plan review should be summarized by the
geotechnical consultant in a letter and submitted to the Town
Engineer for review and approval prior to issuance of building
permits.
Y `I
Nicole Horvitz
Page 3
October 9, 2012
L0079B
2. Geotechnical Construction Inspections — The geotechnical
consultant shall inspect, test (as needed), and approve all
geotechnical aspects of the project construction. The inspections
should include, but not necessarily be limited to: site preparation
and grading, site surface and subsurface drainage improvements,
and excavations for foundations and retaining walls prior to the
placement of steel and concrete. The consultant should complete
an inspection of final site drainage improvements . for
conformance with -geotechnical standards.
The results of these inspections and the as -built conditions. of the
project shall be described by the geotechnical consultant in a
letter and submitted to the Town Engineer for review prior - to
final (as -built) project approval.
L -MUTATIONS
This geotechnical peer review has been performed to provide technical advice to
assist the Town with its discretionary permit decisions. Our services have been limited
to review of the documents previously identified, as well as pertinent office files. Our
opinions and conclusions are made in accordance with. generally accepted principles
and practices of the geotechnical profession. This warranty is in lieu of all other
warranties, either expressed or implied.
Respectfully submitted,
COTTON, SHIRES AND ASSOCIATES, INC.
TOWN GEOTECHNICAL ,CONSULTANT
Ted Sayre
Principal Engineering Geologist
CEG 1795
David T. Schrier
Principal Geotechnical Engineer
GE 2334
TS.DTS:kd
71
Environmentat'Design anis Protection Committee ATTACEMR4 4
Review.ed- by:
Date (Z). (I
Applicant
NPName010IL
Address
Site impact/lighting4o'ise:
Existing Vegetati6n: