1998: The Air Force conducted a successful removal of PCB contaminated soils from a former transformer storage area. First Five-Review conducted for operable units (Ous) 1 – 6 and findings from the review that all cleanup remedies are protective of human health and the environment.

2001: The Air Force conducted a successful removal action of petroleum and lead contaminated soil discovered during excavation activities at a housing construction project.

2002: The State Elmendorf Environmental Agreement (SERA) two party agreement for petroleum releases was dissolved by mutual agreement. All historical releases of petroleum to be regulated by contaminated sites or underground storage tank regulations. For new petroleum releases, a presumptive remedy agreement was signed by the Air Force and DEC which allows the Air Force to take action prior to notifying DEC using four standard protocols listed in the agreement.

2004: Second Five-Year Review conducted for OUs 1, 2, 4, 5 and 6. Findings state the cleanup remedies are protective of human health and the environment for OUs 1, 2, 4, and 6. At OU5, seeps 9, 10 and 11 must be captured and treated by the constructed wetland remediation system to be protective in the long term.

2005: Excavation of soil from a former vehicle maintenance facility (DP098) where the soil is contaminated with chlorinated solvents and petroleum. Natural attenuation combined with long-term monitoring of the groundwater is expected to last several decades.

2006: Treatability study to evaluate enhancement of biodegradation of chlorinated solvents in groundwater was conducted at DP098. Study results show some degradation of chlorinated solvents is possible but slower due to colder climates than in the lower 48. More monitoring is recommended to see if the process of degrading chlorinated products will continue.

2007: Explanation of Signification Differences (ESD) for Operable Unit 6 to cease operations of the selected remedial action (high vacuum extraction system), update the cleanup level for 1,1,2,3-tetrachloroethane in groundwater from a risk-based cleanup level to an established cleanup level in state regulations and clarify how the Air Force will implement land use controls with a 2003 Air Force guidance document.

2008: Third Five-Year Review for OUs 1, 2, 4, 5, 6 and DP098. Findings for all OUs are that the remedies are expected to be protective of human health and the environment upon attainment of groundwater and soil cleanup levels. Exposure pathways which could result in unacceptable risks are being controlled.

2009: Memorandum to the Site File for OUs 1, 2, 4, and 5 on how the Air Force will implement land use controls in accordance with the Air Force’s 2003 Land Use Control Implementation Guidance and it also corrects minor typographical errors in the OU4 Record of Decision which reference incorrect cleanup levels.

2010: Joint basing of Elmendorf Air Force Base and Fort Richardson is finalized in October. The name of the facility will now be referenced as Joint Base Elmendorf Richardson (JBER). SS022 DRMO Yard investigation excavation activities uncover 12 bazooka rockets with live motors which are removed and dealt with by the Explosive Ordinance Detail (EOD).

2011: Memorandum to the Site File for OU2 ST41 Four Million Gallon Hill which provides minor changes to the Record of Decision for OU2. The document provides a site-specific decision tree for sampling frequency for long-term groundwater monitoring and changes sampling frequency for 1 surface water sampling location and a seep location.

2012: Debris at OU6 LF004 Bluff Landfill continues to decline in volume due to the Port of Anchorage expansion in 2008. Only 0.025 tons of nonhazardous solid waste (mostly metal scrap) has been recovered during the annual “beach sweep” activities.

2013: Basewide Uniform Federal Policy-Quality Assurance Project Plan finalized which presents the proposed objectives, methods, and procedures for the Alaska Group Performance-Based Remediation (PBR) Task Order at Joint Base Elmendorf-Richardson (JBER), Alaska. As federal and state regulations, standard operating procedures, and guidance documents change, they will be presented in site-specific work plans referencing the worksheets that they are amending for that specific site/source area.

2014: Fourth Five-Year Review for OUs 1, 2, 4, 5, 6, DP098. The cleanup remedies are generally protective for OUs 1, 2 and 6. At OUs 4, 5, and DP098, protectiveness determinations are deferred due to potential impacts from vapor intrusion pathway at the sites are evaluated.

2015: A new seep at OU5 ST037 wetland remediation system emerged outside of the wetland treatment cell which contained trichloroethylene (TCE) above cleanup levels. It was incorporated into the wetland remediation system for treatment.

2016: Response complete assigned by Air Force for OU6 LF002, due to soil remedies achieving cleanup levels, groundwater meeting cleanup levels since 2003. As a former landfill, LF002 will continue as a “restricted use area” until all waste is removed from the site. Annual land use control inspections continue to be performed at the site.

2017: OU1 LF059 assigned response complete by Air Force, due to groundwater contamination from an upgradient source. New site CG704 will take over groundwater monitoring activities associated with LF059 and any additional site investigation of the unknown upgradient source of groundwater contamination.

2018: Site Investigation finalized for aqueous film forming foam at JBER to determine which source areas have perfluorooctane sulfonate (PFOS) or perfluorooctanoate (PFOA) contamination. 16 source areas have soil above the PFOS/PFOA migration to groundwater cleanup level, 2 source areas have surface water and 14 source areas are above the Table C groundwater cleanup levels for PFOA and PFOS.