HomeMy WebLinkAboutAppendix E.4 - Response to City of San Diego CommentsProject No. 07516-42-02
April 24, 2023
Tri Pointe Homes
13520 Evening Creek Drive North, Suite 300
San Diego, California 92128
Attention: Mr. Allen Kashani
Subject: RESPONSE TO CITY OF SAN DIEGO REVIEW COMMENTS
NAKANO
SAN DIEGO, CALIFORNIA
References: 1. City of San Diego Geology Review Comments prepared by Kreg Mills, dated April 20,
2021.
2. Update Geotechnical Investigation, Nakano Property, Chula Vista, California prepared
by Geocon Incorporated dated September 18, 2020 (Project No. 07516-42-02).
3. Nakano, Grading and Storm Drain, prepared by Civil Sense, Inc., dated May 12,
2022.
Dear Mr. Kashani:
We prepared this letter to respond to City of San Diego LDR-Geology review comments for the subject
project. The review comments pertaining to geotechnical aspects and our responses are presented below.
Issue 15:The project’s geotechnical consultant must submit a geotechnical addendum or update
letter for the purpose of an environmental review that specifically addresses the proposed
development plans and the following:
Response: Based on our review of the referenced plans, the recommendations presented in our
Update Geotechnical Investigation (Reference 2) remain applicable. This response serves
as the requested addendum/update report.
Issue 16:The limits of the proposed development appear to have changed since the submitted report
was prepared. Provide an updated Geologic Map (Figure 2) that shows the current
proposed development. Circumscribe the limits of anticipated remedial grading on the
updated map to delineate the proposed footprint of the project.
Response: Figure 1 is the requested updated geologic map using a CAD file of Reference 3 as the
base map. Figure 1 shows the proposed development and the disturbance limits and limits
of anticipated remedial grading. Cross sections are provided on Figures 2 and 3.
Geocon Project No. 07516-42-02 - 2 - April 24, 2023
Issue 17:Indicate if additional recommendations and/or conclusions are needed to address the
revisions to the development plans.
Response: No additional geotechnical recommendations and/or conclusions are needed.
Issue 18:Indicate if the approximate limits of remedial grading currently shown on the revised
development plans are in accordance with their recommendations.
Response: Along the northern property margin, the limits shown on the development plan did not
match those shown on our geologic map. The civil engineer is revising the development
plan to reflect the limits provided on Figure 1 of this letter.
If there are any questions regarding this correspondence, or if we may be of further service, please
contact the undersigned at your convenience.
Very truly yours,
GEOCON INCORPORATED
Rodney C. Mikesell
GE 2533
RCM:arm
(e-mail) Addressee
(e-mail) Civil Sense, Inc.
Attention: Ms. Maykia Vang
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6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121 - 2974
PHONE 858 558-6900 - FAX 858 558-6159 SHEET OF
PROJECT NO.
SCALE DATE
FIGURE
Plotted:04/24/2023 12:29PM | By:ALVIN LADRILLONO | File Location:Y:\PROJECTS\07516-42-02 (Nakano)\SHEETS\07516-42-02 Geo Map.50.dwg
GEOTECHNICAL ENVIRONMENTAL MATERIALS
1" =
GEOLOGIC 1AP
NAKANO
CHULA VISTA, CALIFORNIA
60'04 - 24 - 2023
07516 - 42 - 02
1 1 1
........UNDOCUMENTED FILL
........ARTIFICIAL FILL
........ALLUVIUM
........TERRACE DEPOSITS
(Dotted Where Buried)
........SAN DIEGO FORMATION (Conglomerate)
........MISSION VALLEY FORMATION
........APPROX. LOCATION OF GEOLOGIC CONTACT
(Queried Where Uncertain)
........APPROX. LOCATION OF BORING
........APPROX. LOCATION OF TRENCH
........APPROX. LOCATION OF INFILTRATION TEST
........APPROX. DEPTH OF REMEDIAL GRADING (In Feet, MSL)
........APPROX. LOCATIION OF GEOLOGIC CROSS SECTION
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D I S T A N C E
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D I S T A N C E
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6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121 - 2974
PHONE 858 558-6900 - FAX 858 558-6159 SHEET OF
PROJECT NO.
SCALE DATE
FIGURE
Plotted:04/24/2023 12:52PM | By:ALVIN LADRILLONO | File Location:Y:\PROJECTS\07516-42-02 (Nakano)\SHEETS\07516-42-02 XSection.50.dwg
GEOTECHNICAL ENVIRONMENTAL MATERIALS
1" =
GEOLOGIC CROSS SEC8ION
NAKANO
CHULA VISTA, CALIFORNIA
60'04 - 24 - 2023
07516 - 42 - 02
1 2 2
........UNDOCUMENTED FILL
........ARTIFICIAL FILL
........TERRACE DEPOSITS
........MISSION VALLEY FORMATION
........APPROX. LOCATION OF GEOLOGIC CONTACT
(Queried Where Uncertain)
GEOCON LEGEND
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0 12060 180 240 300 360 420 480 540 720600660 780 840 900 960 114010201080
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D I S T A N C E
SCALE: 1" = 60' (Vert. = Horiz.)
GEOLOGIC CROSS-SECTION C-C'
D I S T A N C E
SCALE: 1" = 60' (Vert. = Horiz.)
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6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121 - 2974
PHONE 858 558-6900 - FAX 858 558-6159 SHEET OF
PROJECT NO.
SCALE DATE
FIGURE
Plotted:04/24/2023 12:52PM | By:ALVIN LADRILLONO | File Location:Y:\PROJECTS\07516-42-02 (Nakano)\SHEETS\07516-42-02 XSection.50.dwg
GEOTECHNICAL ENVIRONMENTAL MATERIALS
1" =
GEOLOGIC CROSS SEC8ION
NAKANO
CHULA VISTA, CALIFORNIA
60'04 - 24 - 2023
07516 - 42 - 02
2 2 3
........UNDOCUMENTED FILL
........ARTIFICIAL FILL
........TERRACE DEPOSITS
........MISSION VALLEY FORMATION
........APPROX. LOCATION OF GEOLOGIC CONTACT
(Queried Where Uncertain)
GEOCON LEGEND
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