19-23 Proposal_55 Lakeside Avenue-REV.pdf

F:\2021\21-1041 - Township of West Orange Phase I ESAs Downtown Corridor\Proposal\Additional Remedial Investigation - 55 Lakeside\RI Proposal_55 Lakeside Avenue-REV.docx 4 o Soil Borings AOC2B-3R and AOC2B-10 - Horizontal delineation of TCE to the east and south of soil boring AOC2B-5 o Soil Boring AOC2B-11 - Horizontal delineation of TCE to the west of soil boring ACO2B-7 All samples will be analyzed by a New Jersey certified laboratory on a standard turnaround time basis. The borehole will be backfilled with soil cutting collected and ground surface shall be patched with concrete. Please note Matrix will collect contingent delineation samples and only run if the initial delineation samples identified above exceed the applicable NJDEP Soil Remediation Standards. Projected costs include one one-day mobilization for interior soil investigations. Soil Sample summary table is attached for reference. Groundwater Investigation Based on the groundwater sampling activities to date, chlorinated VOCs (CVOCs specifically Trichloroethene [TCE]), Polycyclic Aromatic Hydrocarbons (PAHs) and metals were identified at concentrations above the NJDEP’s Groundwater Quality Standards (GWQS). All monitoring wells will be gauged, and up to one additional round of groundwater sampling will be completed. The groundwater samples will be collected from the monitoring wells (up to 20 wells per sampling event including the DPW monitoring wells) via low flow sampling technique. The groundwater samples will be analyzed for TCL VOC+15. In additional, Metals will be collected from select monitoring wells including MW-2 at the DPW. Water quality indicator parameters (dissolved oxygen, pH, temperature, conductivity, and ORP) will be monitored during the groundwater purging and sampling activities. For QA/QC purposes, one field blank, and one trip blank will also be collected. All groundwater samples will be analyzed on a standard turnaround time basis by a New Jersey certified laboratory. Matrix will arrange for the disposal of the non-hazardous investigative derived waste (IDW), up to 20 55-gallon drums. The IDW consist of soil cuttings and monitoring well purge water generated during well development and groundwater sampling activities. TASK 3: REMEDIAL INVESTIGATION REPORT AND REMEDIAL ACTION WORKPLAN PREPARATION AND SUBMITTAL Upon receipt of the additional RI soil sampling results,

l development and groundwater sampling activities. TASK 3: REMEDIAL INVESTIGATION REPORT AND REMEDIAL ACTION WORKPLAN PREPARATION AND SUBMITTAL Upon receipt of the additional RI soil sampling results, Matrix will evaluate the various functional areas and conduct compliance averaging as outlined in NJDEP Guidance to minimize soil excavation. A Remedial Investigation Report (RIR) and Remedial Action Workplan (RAW) and associated forms will be prepared and will summarize the results of the remedial investigation for soils, groundwater, sediments, surface water, and vapor intrusion, and the proposed remedial action. Following a review of the Draft Report by the Township of West Orange, comments will be incorporated to prepare the Final RIR/RAW that will be submitted to NJDEP. The following forms may be required during the RI/RAW: • Case Inventory Document (CID) • Authorization to Submit a Report Through NJDEP Online • Cover/Certification Form • CEA Fact Sheet • Updated Receptor Evaluation including well search spreadsheet • Alternative or New Remediation Standard and/or Screening Level Application Form