The former hangar was identified as a possible source of contamination during the 2002 Remedial Process Optimization review due to past use as a military hangar. Upon further historical record research, though, it was found that the building was primarily used for administrative offices and recreational purposes. A soil gas survey completed in 2003 did not indicate any significant contamination. The site is not in the Air Force Installation Restoration Program as a contaminated site. It was investigated only as an area of concern. Site SS014 was also referred to as Area of Concern [AOC] 1 or ST014 in historical documents. The site consists of the building 1551 (Former Birchwood Hanger) which was constructed in 1945. The building was demolished in 2001. The concrete slab foundation was left in place. The site also included UST1551-1, UST1558, OWS1551. The 2007/2008 remedial investigation showed contaminant concentrations above the Table B1 Method 2 levels for benzene, ethyl benzene, and 1,2,4-trimethylbenzene. The currently known distribution of soil contamination centers on the location of the former UST (central northern edge of the hanger). However, the lateral and vertical extent of soil contamination has not been defined. During a collaborative May 2009 TPT meeting that addressed site data gaps: The stated contaminants of concern are DRO and VOCs. Three groundwater monitoring wells/drive points were proposed with one installed north of the hanger and the remaining two installed at locations of highest groundwater contaminant concentration across the southern edge of the hangar foundation. Groundwater contaminants recommended for monitoring and continued evaluation include DRO, benzene, ethyl benzene, and 1,2,4-trimethylbenzene