87th Air Base Wing Joint Base McGuire-Dix-Lakehurst Public Meeting – March 14, 2019 Proposed Plan Dix – Site NW042 (0900 Area)
87th Air Base Wing Mr. Curtis Frye, P.E. Chief, Environmental Restoration Program, JB MDL AFCEC/CZOE Mr. David Heuer, Phase Manager, Arcadis
Public Meeting Purpose U.S. Air Force is inviting the public to comment on the ◼ proposed environmental actions for the Dix Site NW042 (0900 Area) The opening of a 30-day public comment period was posted in ◼ the Asbury Park Press and Burlington County Times and started March 3 rd and will end April 2, 2019 Comments from the public may be submitted tonight (verbally ◼ or written), or sent to Curtis Frye (mail or e-mail) “WIN AS ONE” 3
Status of CERCLA* Process ✓ Remedial Investigation (RI) - characterization of site ✓ Feasibility Study (FS) - assessment of possible remedies ✓ Proposed Plan (PP) - solicit public input on preferred remedy ❑ Record of Decision (ROD) - legal documentation of remedy selection ❑ Remedial Design (RD) - remedy implementation plan ❑ Remedial Action (RA) - remedy implementation *Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Preliminary Site Remedial Feasibility Proposed Record of Remedial Remedial Long Term Assessment Inspection Investigation Study Plan Decision Design Action Management 4
Proposed Plan Provides information necessary to allow the public to participate ◼ in selecting the appropriate remedial alternatives ◼ The Proposed Plan ▪ Summarizes site history, investigations, and results of human health and ecological risk assessments ▪ Describes remedial alternatives considered ▪ Provides a comparative analysis of remedial alternatives based upon USEPA established criteria ▪ Presents the preferred remedial alternative ▪ Contains information on community participation “WIN AS ONE” 5
Presentation Agenda Background ◼ Conceptual Site Model ◼ Remedial Action Objectives ◼ Technology Assessment ◼ Assembly and Evaluation of Alternatives; and Identification of the ◼ Preferred Remedy Public Comment Period Information ◼ “WIN AS ONE” 6
Background 7
NW042 Site Location NW042 SITE “WIN AS ONE” 8
NW042 Site Plan “WIN AS ONE” 9
NW042 History ◼ ~40 acre site ◼ Currently vacant grassy land ◼ Military Housing 1955 to 1994 (Kennedy Court Housing complex) • 400 family units in 64 buildings ◼ Undeveloped land prior to construction of housing Photo-credit: Arcadis site investigation photo 10
Summary of Historical Investigations ◼ 2009 surface soil sampling completed by Ft. Monmouth DPW • 102 soil samples collected around former Buildings 923 through 933 for pesticides ◼ August and September 2009 Site Investigation • Geophysical survey (i.e., exploration for potential USTs) • Sitewide, 36 soil borings sampled for VOCs, SVOCs, and metals • 3 temporary wells sampled for VOCs, SVOCs, metals, and pesticides • 12 surface soil samples for PCBs targeting fallen pole-mounted transformers • Buildings 923 through 933, 50 shallow soil borings sampled for pesticides “WIN AS ONE” 11
Summary of Historical Investigations continued ◼ 2012-2013 Remedial Investigation • 472 soil samples collected from 135 soil borings • 18 direct-push technology groundwater samples • 11 monitoring wells installed; 25 groundwater samples collected from wells ◼ The RI focused on a subset of five former buildings (923 through 927) with an extensive sampling program to precisely define nature and extent of impacts and support a thorough Conceptual Site Model (CSM) for the entire site “WIN AS ONE” 12
Conceptual Site Model 13
Investigation/Sampling 2009 through 2012 Impacted media limited to soil near former buildings. Groundwater is not impacted. 14
Nature and Extent ◼ Site soil impacted by three pesticides at concentrations exceeding the Residential Direct Contact Soil Remediation Standards (RDCSRSs) • Alpha chlordane (RDCSRS 0.2 mg/kg) • Gamma chlordane (RDCSRS 0.2 mg/kg) • Dieldrin (RDCSRS 0.04 mg/kg) ◼ Pesticide impacts generally limited to the interval between 2 and 4.5 feet below ground surface near former buildings; no impacts to soil in courtyard areas or in soil 25 feet from former buildings ◼ No VOC, SVOC, PCBs, or metals impacts to soil ◼ Groundwater is not impacted “WIN AS ONE” 15
Source and Distribution Pesticides: alpha chlordane, gamma chlordane, and dieldrin Impacts limited to shallow soil near former housing 16
Remedial Action Objectives (RAOs) 17
Feasibility Study ◼ Feasibility Study (FS) was conducted to evaluate possible remedial alternatives at this site ▪ Trigger for remediation: Pesticides were identified in soils at concentrations above the New Jersey Residential Direct Contact Soil Remediation Standards (RDCSRSs). ▪ Soil is the only media impacted at the site ▪ No action required for groundwater ▪ Surface water and sediment are not present at the site “WIN AS ONE” 18
Remedial Action Objectives ◼ The following RAOs were established for Dix Site NW042 (0900 Area) and are presented below: • RAO No, 1: To prevent human exposure to soil by the direct contact pathway (i.e., inhalation and ingestion-dermal pathways) that would cause unacceptable risk to human health, thereby allowing for unlimited use/unrestricted exposure. • RAO No. 2: To achieve the applicable NJDEP RDCSRS for the identified COCs in soil in a reasonable timeframe, thereby restoring the Site for unlimited use/unrestricted exposure. “WIN AS ONE” 19
Preliminary Remedial Goals “WIN AS ONE” 20
Technology Assessment 21
Pre-Design Investigation 2017 ◼ August 2017 Pre-Design Investigation • 171 subsurface soil and 27 surface soil samples collected for alpha chlordane, gamma chlordane, technical chlordane, and dieldrin ◼ The PDI sampling was completed to confirm the CSM developed during the RI and obtain data to determine site-wide compliance status ◼ The evaluation of Site soils was completed in accordance with the NJDEP Historically Applied Pesticide Technical Guidance (NJDEP 2016) and Technical Guidance for Attainment of Remediation Standards and Site-Specific Criteria (September 2012). • A site-wide average concentration can be calculated to determine compliance with the applicable soil standards using NJDEP-approved statistical calculations “WIN AS ONE” 22
Investigation/Sampling 2017 Soil sampling at Former Buildings 923 through 933 completed during SI/RI phase PDI sampling confirmed the CSM and provided data for compliance calculations. 23
Baseline Compliance Status • Site-wide spatially-weighted average calculated using the Thiessen Polygon method in accordance with NJDEP guidance. • Used all available data from the SI (AMEC 2009), RI (CB&I 2014), and pre- design sampling (2017). • 308 data points across 40 acres (approximately 8 samples per acre) “WIN AS ONE” 24
Targeted Remediation Areas • The compliance averaging calculations were performed by replacing the concentrations of the two highest baseline total chlordane (alpha and gamma) concentration polygons • SB-243 and SB217 – total area 0.3 acres; volume 2,420 cubic yards) • Used a typical soil quality concentration (0.5 mg/kg) resulting from soil mixing (estimated total chlordane was 0.5 mg/kg per the pilot study results provided in FS [Arcadis 2016]). “WIN AS ONE” 25
Technology Assessment Blending/ • In-Situ Soil Mixing Mixing Removal and • Soil Excavation and Offsite Disposal Disposal Treatment • Ex-Situ Soil Treatment and Backfill “WIN AS ONE” 26
In-Situ Soil Mixing Pilot Testing ◼ August 2015 Pilot Test for In-Situ Soil Mixing • Three mixing scenarios were implemented in three different test cells • Baseline and two rounds of post mixing soil sampling were completed • Objective was to determine effectiveness and viability of mixing to support evaluation of this potential alternative in the FS (results included as appendix to the FS [Arcadis 2016]. “WIN AS ONE” 27
In-Situ Soil Mixing Image Credit: 2015 Soil Mixing Pilot Test, Site NW042 28
Removal and Disposal Soil Excavation and Offsite Disposal Image Credit: Excavation remedy at McGuire 29
Treatment Ex-situ Soil Treatment Image Credit: Site remediation project, Arcadis NA 30
Assembly and Evaluation of Alternatives; and Identification of the Preferred Remedy 31
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