ARCHIVED REPORTS XR0011651 - Laserfiche WebLink

Home Browse Search

KLEINFELDER I 5 0 CONCLUSIONS & RECOMMENDATIONS Based on the results of Kleinfelder's limited soil and groundwater assessment, the following ' conclusions can be made 1 Total lead concentrations and xylenes detected in soil were found to be below the TTLC ' and ten times the STLC regulated levels as expressed in California Code of Regulations 22CCR§66261 24 and/or Residential and U S EPA Region TX Preliminary Remediation ' Goals (PRGs), dated October 1, 2002 and as summarized in Section 4 The total lead concentrations in soil in Kleinfelders opinion are representative of naturally occurring background concentrations Please note the client should contact the signatories of this ' report for additional consultation prior to any off site disposal Many disposal facilities have gate acceptance criteria, which must be satisfied prior to transportation and disposal Therefore, additional analysis may be required prior to full waste classification 2 Groundwater was encountered at depths ranging from 10 to 19 feet bgs, and appeared to stabilize at depths ranging from 10 to 12 feet bgs Groundwater flow direction based on ' assessments of adjacent sites in the area is generally to the north/northeast Typical depth to groundwater in this area of the project is generally 10 to 12 feet bgs Please note local pumping and tidal fluctuations can affect the depth to groundwater 3 Groundwater contaminants including one or more of seven analytes/compounds exceed either State and Federal MCLS or the City's acceptance criteria for discharge to the ' sanitary sewer Said groundwater contaminants span at least 600 feet of the proposed pipeline alignment Kleinfelder estimates groundwater beneath approximately 700 linear feet of pipeline routing is affected by groundwater contaminants extrapolating between ' the non-detected groundwater sampling points to the east and west and to the closest sampling points noted with groundwater contamination 4 The greatest concentration of groundwater contamination appears to be located along approximately 400 linear feet noted between DW-51 to GP-3 Elevated MTBE concentration (51 to 62 µg/1) were noted by GPI/DW-52 Elevated DCE compounds ' were noted near GPI and GP2 PCE was detected in groundwater collected from DW- 51, potentially indicating a source area not noted by PHS/EHD ' 5 In the event of dewatering operations in the Franklin area, it is likely that groundwater contamination from adjacent sites to the north (2151, 2103 and 2081 Country Club) may cause an increase in contaminant concentrations in groundwater or introduce contaminants not detected in this assessment Additionally, extensive pumping may also affect the size and location of the existing and adjacent groundwater plumes from these ' sites, causing additional remediation costs and potential increased liability 28699 EOI I ST03R759 page 13 of 17 Copyright 2003,Kleinfelder, Inc May 20,2003