Site-Specific Health and Safety Plan (HASP) - Laschools.org

RESPONSES TO COMMENTS FROM DTSC DATED JULY 22, 2008
DRAFT OPERABLE UNIT 1A REMEDIAL ACTION PLAN
PROPOSED SOUTH REGION HIGH SCHOOL #9 AND MIDDLE SCHOOL #4, SOUTH GATE (#304440)
Comment
Number
Comment Response
Comments from Joe Hwong, P.G. C. HG. General Comments
1 Since OU4 is newly added to the Operable Units at the Site, its
cover area should be clearly defined in the revised RAP. In
addition, Figures 1-2 and 2-1 should be re-drawn to depict
OU4's boundary.
2 Figure 3-1 - If Area OU1B does no longer exist during future
remedial activities, DTSC recommends it be removed from the
OU1A RAP and Figure 3-1.
3 Incorporate the DTSC Geologist's comments in the revised
OU1A RAP.
Comments from Bruce Garbaccio, P.G. General Comments
1 The RAP discusses volumes of soil to be segregated as RCRA
waste, California Hazardous, TSCA waste, and non-hazardous
waste. DTSC recommends that a map be included that shows
the areas with each waste type.
2 Confirmation Sampling - The text (Sections 5.3 and 7.6.2)
describes confirmation sampling procedures. They indicate a
sampling rate of 1 per 500 square feet will be collected. DTSC
concurs with the strategy for the bottom samples, which gives
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(7/28/08)
Response – Information regarding OU 4 has been detailed and
appropriate changes made in the revised RAP to Figures 1-2 and 2-1 to
reflect the location of the OU 4 boundary. In addition, newly
designated OU 5 (Tweedy Boulevard west of Adella Avenue) has been
depicted.
Response – Comment noted. The revised RAP, including Figure 3-1,
has been modified to remove reference to Areas A and B.
Response – Responses to the DTSC Geologist’s comments have been
incorporated in the revised OU 1 RAP.
Response – A map outlining the locations of different waste types has
been added to the revised RAP and is included as Figure 5-1. This is an
estimate based on available site characterization data. Also note that a
portion of the waste is classified as both a TSCA waste (because of
PCBs) and as a RCRA waste (because of metals). The waste estimates
in the revised RAP have been revised to reflect this.
Response – Additional soil confirmation samples will be collected at a
rate of one sample per 20 to 30 of linear feet of sidewall. Figure 5-2 has
been revised to reflect additional confirmation sampling at Parcel 29.
This includes new samples 029-PC054 through 029-PC076.
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