SWMU 56 – Hanger 200 Apron

SWMU 56 is located on the south side of the airfield, just off of the aircraft apron on the northwest side of Hangar 200. Historic records reviews confirmed the hangar’s use for aircraft maintenance and identified stains/liquid extending off the edge of the hardstand to a surrounding drainage ditch. No significant stains or stressed vegetation were observed upon physical site inspection; however, interviews confirmed numerous past spills of petroleum, oils, and lubricant (POL) and hazardous materials from the 1950s to the 1990s.

Sediment and surface water samples were collected from the drainage ditch to characterize the site.  Analytical data confirmed that site contamination is primarily related to past activities.

Status

• The RCRA 7003 Administrative Order on Consent recommends a Corrective Measures Study (CMS) Work Plan for the Hangar 200 Apron.
• The Final CMS Work Plan for SWMU 56 was submitted on December 6, 2007 and approved by the EPA on April 10, 2008.
• CMS Field Investigation was completed June 2008.
• The Draft Corrective Measures Study Report was submitted to the EPA on September 26, 2008.
• A Functional Assessment and Supplemental Sediment Sampling was conducted and submitted to the EPA on December 3, 2009.
• A Letter Report-SWMU 56/56A Source Area Investigation Report was submitted to the EPA April 23, 2010.
• Navy requested an extension for the revised Draft CMS for SWMU 56 until October 2010.
• A Revised Draft Corrective Measures Study Report for SWMU 56 was submitted to the EPA on October 29, 2010.
• The Final Corrective Measures Study Report for SWMU 56 was submitted to the EPA on September 29, 2011 in accordance with comments received from the EPA on March 11, 2011.