Скачать презентацию Presentation for City of Brisbane Final Peer Review Скачать презентацию Presentation for City of Brisbane Final Peer Review

2c53c3bdd7895e94941eaec8ecd5198d.ppt

  • Количество слайдов: 38

Presentation for City of Brisbane Final Peer Review Findings November 7, 2005 (Revised May Presentation for City of Brisbane Final Peer Review Findings November 7, 2005 (Revised May 10, 2006)

Presentation Outline u Purpose u Project Overview u Summary of Findings u Background and Presentation Outline u Purpose u Project Overview u Summary of Findings u Background and Regulatory Framework u Objectives and Evaluation Criteria u Findings u Recommendations u Discussion

Purpose u Update April 2005 workshop u Supplemental data u Refine findings u Information Purpose u Update April 2005 workshop u Supplemental data u Refine findings u Information to date u Update recommendations

Project Overview u Baylands project area u u Former Brisbane landfill Southern Pacific Railroad Project Overview u Baylands project area u u Former Brisbane landfill Southern Pacific Railroad facility u Phase 1 development u Former Brisbane landfill u Future development phases u Southern Pacific Railroad facility

Site Map Modified from Workshop Presentation to the City of Brisbane, Brisbane Baylands, Subsurface Site Map Modified from Workshop Presentation to the City of Brisbane, Brisbane Baylands, Subsurface Environmental Conditions by Universal Paragon Corporation and Burns & Mc. Donnell Engineering Company, Inc. , November 18, 2003.

Summary of Findings – Landfill Evaluation category Risk assessment • Human health • Ecological Summary of Findings – Landfill Evaluation category Risk assessment • Human health • Ecological Assessment • Evaluations incomplete • Final assessments pending Limits of waste • Adequately defined, except for southern boundary • Agree with plan to extend landfill cap to edge of Guadalupe Channel Landfill Settlement • Evaluation incomplete • Future studies needed Landfill gas • Concur majority of organic waste is decomposed • Recommend re-initiation of monitoring activities Groundwater Quality • Adequately characterized. Leachate • Seeps into surface and groundwater adequately characterized Remedial approach • Evaluation incomplete – dependent on approved development plan • Final closure plan not prepared but will address: • Gas control system • Final cover and surface water control • Settlement • Human Health and Ecological assessments

Summary of Findings – OU-1 Evaluation category Risk assessment • Human health • Ecological Summary of Findings – OU-1 Evaluation category Risk assessment • Human health • Ecological Assessment • Evaluations incomplete • Final assessments pending Groundwater • Generally adequately characterized • Treatment system mitigates infiltration into Sunnydale Sewer • Additional information is needed for • DNAPL source (residual or upgradient) • A-aquitard discontinuity/B-Aquifer contaminant mechanism • RAP in DTSC review Soil • Evaluation incomplete • DTSC request additional work – • Site characterization • Remedial action workplan Surface water • Adequately characterized • Groundwater treatment system mitigates infiltration into Sunnydale Sewer Soil vapor • Future studies likely needed based on final development plan Remedial approach • • Evaluation incomplete Remedial action plans in review/preparation Overall proposed approach consistent with industry practice Final RAP dependent on approved development plan

Summary Findings – OU-2 Evaluation category Risk assessment • Human health • Ecological Soil Summary Findings – OU-2 Evaluation category Risk assessment • Human health • Ecological Soil & groundwater Soil vapor Surface water Remedial approach Assessment • Evaluations incomplete • Final assessments pending • Adequately characterized • Depending on final approved development plan, future studies may be required • Adequately characterized • Interim approach consistent with industry practice • Soil vapor study may be required for potential vapor migration • Final RAP dependent on approved development plan • Adoption of future RWQCB Site Cleanup Order

Background and Regulatory Framework u Brisbane Landfill u u Former municipal landfill (1933 -1967) Background and Regulatory Framework u Brisbane Landfill u u Former municipal landfill (1933 -1967) RWQCB and County of San Mateo Environmental Health Division (County) u Groundwater Operable Unit 1 (OU-1) u u Former Southern Pacific Railroad Facility (19141960) and Schlage Lock Facility (1926 -1999) California Department of Toxic Substances Control (DTSC) u Groundwater Operable Unit 2 (OU-2) u u Former Southern Pacific Railroad Facility (19141960) RWQCB

Objectives and Evaluation Criteria u Objectives u u u Provide independent technical review Serve Objectives and Evaluation Criteria u Objectives u u u Provide independent technical review Serve as community advocate Support the dissemination of project information u Evaluation Criteria u u u Adequacy of environmental characterization Appropriateness of remedial action Protective of public health and environment

Peer Review Role In Baylands Planning Process Peer Review Role In Baylands Planning Process

Findings – Brisbane Landfill Adequacy of Environmental Characterization u Evaluation adequate – – u Findings – Brisbane Landfill Adequacy of Environmental Characterization u Evaluation adequate – – u Limits of waste, except for southern boundary Landfill gas Groundwater quality Leachate Evaluation incomplete – Landfill settlement

Findings – Brisbane Landfill Cont. u Appropriateness of Remedial Action u u Final remedial Findings – Brisbane Landfill Cont. u Appropriateness of Remedial Action u u Final remedial action plan not developed Primary issues associated with landfill closure – – – u Landfill gas generation and migration Leachate generation and transport into groundwater and surface water Settlement of the landfill surface Proposed concept is appropriate – Lacks sufficient detail

Remedial Approach – Brisbane Landfill Remedial Approach – Brisbane Landfill

Findings – Brisbane Landfill Cont. Protective of Public Health and Environment u Overall concept Findings – Brisbane Landfill Cont. Protective of Public Health and Environment u Overall concept appropriate – final evaluations not complete u u Final closure plan - not prepared Final risk assessments - not prepared u Human health u Primary concern – Landfill gas u Ecological u Primary concern – Leachate seeps

Findings – Operable Unit 1 Adequacy of Environmental Characterization u Primary site contaminants u Findings – Operable Unit 1 Adequacy of Environmental Characterization u Primary site contaminants u VOC’s, TPH as Bunker C, metals u Soil – Evaluation incomplete u Additional investigation requested by DTSC u Revised RAP in progress u Groundwater – Generally characterized u Clarification needed for: – – A-zone aquitard continuity (‘windows’) B-zone contamination source u Soil Vapor – Evaluation incomplete u Risk Assessments – Evaluation incomplete u Pending final development plan

Site Map – Operable Unit 1 Site Map – Operable Unit 1

Stratigraphic Terminology Possible Gap Stratigraphic Terminology Possible Gap

Simplified Conceptual Aquifer Development West East Simplified Conceptual Aquifer Development West East

Findings – Operable Unit 1 Cont. Appropriateness of Remedial Action u Remedial approach u Findings – Operable Unit 1 Cont. Appropriateness of Remedial Action u Remedial approach u u Limited soil excavation at two locations (VOCs) Continued operation of groundwater treatment system – – u u u Add three extraction wells Add two monitoring wells Soil cap Vapor barriers, as needed Engineering and Institutional Controls – Reduce/eliminate human health exposure

Proposed Remedial Action – Operable Unit 1 (Profile) Proposed Remedial Action – Operable Unit 1 (Profile)

Proposed Remedial Action – OU-1 Commercial Scenario Engineering Control – Restrict Groundwater Use Engineering Proposed Remedial Action – OU-1 Commercial Scenario Engineering Control – Restrict Groundwater Use Engineering Control – Outdoor Inhalation Engineering Control – Indoor Inhalation Legend Proposed Area of Soil Removal Proposed Additional GW Monitoring Well Proposed Additional GW Extraction Well Modified from Burns & Mc. Donnell, Revised Groundwater RAP, Operable Unit 1, January 27, 2005.

Findings – Operable Unit 1 Cont. Protective of Public Health and Environment u Evaluation Findings – Operable Unit 1 Cont. Protective of Public Health and Environment u Evaluation incomplete u u u Site RAPs not complete Final development plan pending Proposed remedial concept – generally acceptable u Human health u Final risk assessment pending u Ecological u u Assessment not performed/identified Final risk assessment recommended

Findings – Operable Unit 2 Adequacy of Environmental Characterization u Primary site contaminants: u Findings – Operable Unit 2 Adequacy of Environmental Characterization u Primary site contaminants: u TPH as Bunker C, metals, VOCs u Soil and groundwater – adequately characterized u Surface Water - adequately characterized u Soil Vapor – evaluation incomplete u Risk Assessments – evaluation incomplete u Pending final development plan

Findings – Operable Unit 2 Cont. Appropriateness of Remedial Action u Remedial approach (interim) Findings – Operable Unit 2 Cont. Appropriateness of Remedial Action u Remedial approach (interim) u Soil Cap - 7 to 10 feet clean soil – – u Abandon existing north-south drainage channel – u Leave in-place TPH and metals impacted soils Limited VOC soil removal (Spring 2006) Replace with interim drainage channel (Spring 2006) Engineering and Institutional Controls – – Reduce/eliminate human exposure Not defined/delineated

Site Contaminants – Operable Units 1 and 2 Site Contaminants – Operable Units 1 and 2

Proposed Remedial Action – Operable Unit 2 Proposed Remedial Action – Operable Unit 2

Findings – Operable Unit 2 Cont. Protective of Public Health and Environment u Evaluation Findings – Operable Unit 2 Cont. Protective of Public Health and Environment u Evaluation Incomplete u Interim RAP approved by RWQCB u Final Site RAP pending u RWQCB Site Cleanup Order pending u Human health u Proposed remedial concept – generally acceptable – – – Final risk assessment pending Evaluate for applicability to current standards Soil vapor not evaluated u Ecological – acceptable u Proposed concept addresses ecological risk – – u Based on SFIA values Evaluate for applicability to current standards Overall interim concept appropriate – final evaluation not complete

Recommendations u General u Subarea specific u u u Brisbane landfill OU-1 OU-2 u Recommendations u General u Subarea specific u u u Brisbane landfill OU-1 OU-2 u Next steps u Note: not all steps required immediately

Recommendations – General u Financial assurance u Mechanism to manage long-term uncertainties associated with Recommendations – General u Financial assurance u Mechanism to manage long-term uncertainties associated with maintenance of streets, utilities, etc u Conceptual site model and remedial action plan u u u Integrated development-based Baylands plan Establish evaluation and remedial approach Develop early in project approval process u Continue evaluation of Baylands environmental documents and plans

Recommendations – Brisbane Landfill u Risk assessment u u Final human health assessment Ecological Recommendations – Brisbane Landfill u Risk assessment u u Final human health assessment Ecological assessment u Landfill surface settlement evaluation u Settlement studies u Final cover design and construction u Landfill cover – – Single, integrated unit Prevent surface water infiltration and minimize leachate seeps

Recommendations – Brisbane Landfill Cont. u Landfill gas and monitoring u u Vapor barriers Recommendations – Brisbane Landfill Cont. u Landfill gas and monitoring u u Vapor barriers & methane monitoring Explosion proof construction – underground utilities u Groundwater monitoring u Post-closure monitoring program u Post-closure monitoring and maintenance plans

Recommendations – Operable Unit 1 u Provide additional information to address: u u Soil Recommendations – Operable Unit 1 u Provide additional information to address: u u Soil contamination – type and extent Groundwater – – – A-aquitard ‘windows’ DNAPL source B-Sand aquifer – VOC source u Consider benefits of in-situ treatment technologies u u Source reduction Augment proposed final remedial approach u Human health and ecological risk u Complete final assessments

Recommendations – Operable Unit 2 u Update soil remedial action plan u VOC soil Recommendations – Operable Unit 2 u Update soil remedial action plan u VOC soil vapor u Update soil management plan and residual risk management plan u Consider in-situ bioremediation treatment u u Source reduction Augment proposed final remedial approach u Human health and ecological risk u Complete final assessments

Recommendations – Operable Unit 2 Cont. u Prepare monitoring plan for post well abandonment Recommendations – Operable Unit 2 Cont. u Prepare monitoring plan for post well abandonment and replacement plan u Assess the brick-lined arch sewer u Structural integrity for proposed tie-in u Evaluate long-term settlement u Final remedial approach consistent with future RWQCB site cleanup order

Recommendations - Next Steps u Develop integrated site conceptual model and development-based Remedial Action Recommendations - Next Steps u Develop integrated site conceptual model and development-based Remedial Action Plan u City meet with regulatory agencies to discuss path forward with respect to future requirements u Review revised specific plan and development concept u Evaluate future environmental documents as deemed necessary

Future Studies and Sequencing Future Studies & Program Sequence A OU-1 OU-2 B Prior Future Studies and Sequencing Future Studies & Program Sequence A OU-1 OU-2 B Prior to/concurrent with CEQA C Required by CEQA D Landfill Supplemental Data Review Development Plan E Post Development Plan

Discussion Discussion