Luke Air Force Base

Planes taxiing on runway at Luke Air Force Base

Luke Air Force Base | Site History: Page 3 of 3

As part of the LAFB LTM Work Plan, an annual inspection at site ST-18 included a detailed visual observation of the concrete cap. The inspection consisted of walking several transects across the concrete cap area and noting visual cracks, joints, former penetrations, and other features of interest (such as previous repairs) that may affect the integrity of the cap. The 2009 annual inspection indicated that the cap has been maintained per the ROD, is still functioning as intended, and remains an effective barrier to surface water infiltration.

2010 - 2011: Annual reports were reviewed by ADEQ and EPA, which included the Potential Source of Contamination (PSC) ST-18 concrete cap inspection report, the annual radiation monitoring report and the annual groundwater monitoring report. Results for the PSC ST-18 concrete cap inspection report concluded that minor repairs to the cap were required in order to maintain its integrity including sealing cracks and gaps. It was recommended that the cap be replaced in the future. Results for the annual radiation monitoring report concluded that the containment structure for the radiological material remains intact and that the surrounding soil does not appear to have been impacted by this material. Results for the annual groundwater monitoring reports for 2010 and 2011 concluded that results were consistent with previous year's annual monitoring data, with a slight increase in groundwater elevation. In 2011, the groundwater elevation of the site was approximately 240 feet below ground surface (bgs).

2012: The third FYR report was finalized in September. It summarized the status of the remedies implemented at ten sites identified in the OU-1 and OU-2 ROD at LAFB which included soil treatment, source capping, groundwater monitoring, gamma radiation monitoring, and institutional controls (ICs).  The third FYR report discusses the following ten sites that required a remedy, as determined from the results of the remedial investigation (RI):

  • Drainage Ditch Disposal area (DP-13)
  • Eastern portion of North Fire Training area (FT-07E)
  • Outboard Runway Landfill (LF-03)
  • Old Salvage Yard Burial site (LF-14)
  • Northwest Landfill (LF-25)
  • Wastewater Treatment Annex Landfill (RW-02)
  • Oil/Water Separator at Auto Body Shop (SD-38)
  • Bulk Fuels Storage area (SS-42)
  • Former Liquid Waste Storage Facility (Facility 993) (ST-18)
  • Old Surface Impoundment West of Facility 993 (DP-23)

The assessment conducted as part of this FYR found that the remedies required at the OU-1 and OU-2 sites were implemented in accordance with the requirements of the RODs. All remedies are functioning as designed, continue to be protective of human health and the environment, and control exposure pathways that could result in unacceptable risks. The next FYR will be due January 30, 2017.

2013: In Sept., the performance based remediation contract was awarded. The annual long term monitoring activities were performed. Results for the annual groundwater monitoring reports concluded that results were consistent with previous year’s annual monitoring data.

2014 - 2015: Soil sampling activities were performed at sites FT-07E and ST-18 in the later part of 2014. Results were submitted to ADEQ in 2015. Site SS-42 will continue to undergo annual groundwater monitoring sampling events.