Landfill No. 4 (LF004)

• Record of Decision Amendment completed in 2014

Parcel N (XU403a & XU403b)

• Site Inspection completed in 2018
• Currently in Remedial Investigation (RI)

Area 5 Surface Rubble (XU403d)

• Currently in Site Inspection  

Liquid Fuel Storage Facility (ST012)

• Record of Decision Amendment 2 completed in 2013
• Currently in Long-term Monitoring
  • Steam-enhanced extraction was implemented from September 2014 through April 2016
  • Enhanced Bioremediation was initiated in November 2018
  • Phases 1 and 2 for additional monitoring wells completed in 2021 and 2023
  • Vapor intrusion (VI) preliminary evaluation completed in 2022

ST035 (Building 760)

• Corrective Action completed in 2017
• Leaking Underground Storage Tank (LUST) Case Closure Notice of Decision issued in 2018 closing the site 

Basewide 

• Fifth Five Year Review (FYR) completed in September 2023. FYR includes OUs 1-6.  
• PFAS Site Inspection (SI) completed in 2020 for aqueous film-forming foam sources.

Declaration of Environmental Use Restriction (DEUR) & Voluntary Environmental Mitigation Use Restriction (VEMUR)

• DEURs were placed on 9 subsites between the years of 2007 and 2022, which included subsites SS016, SS017, SS020 (both skeet range and firing range), SS021, SS024, DP028, FT002, and ST012.
• VEMURs were placed on 5 subsites between the years of 1997 and 1999, which included Facility 46, Facility 114, Facility 1013, SS016, and SS019.

In Long-term Monitoring which consists of operation and maintenance requirements of the landfill. 

Annual landfill cap inspections and maintenance are performed, in-well air stripping and soil vapor extraction (SVE) system sampling and maintenance activities performed on quarterly basis, and periodic oxidant injections continue to address residual contaminants in groundwater and semi-annual groundwater monitoring.

SI milestone phase of planning which includes but not limited to, funding, contracting, and completion of project plans before fieldwork can begin.

RI milestone phase of planning which includes but not limited to, funding, contracting, and completion of project plans before fieldwork can begin.

In Remedial Action and Long-term Monitoring milestone phases.

Currently in the field and reporting stages that includes but not limited to maintaining the SVE treatment system, removal of free product, and semi-annual monitoring events. Groundwater semi-annual monitoring events will continue until attainment of all cleanup levels has been achieved. VI continues to be evaluated at the site. 

• This site is subject to programmatic FYRs and the next review will be conducted in September 2026. 
• PFAS is currently in the RI phase and in the planning efforts. 

DEUR and VEMUR requirements continue across all sites | Learn More About DEURs >