REMEDIAL ACTION WORK PLAN OPERABLE UNIT 2, LANDFILL ...

.7-”” “ The 0U2 Landfills are located north and south of Imjin Road in the Main Garrison Area
(Location Map, Figure 1-2). Area A, the only landfill north of Imjin Road and the only one with
surface developments, covers approximately 25 acres. The landfills south of Imjin Road, Areas
B through F, encompass approximately 93 acres of undeveloped land. They are covered by
uneven sand dunes and grass, shrubs, and bushes. Surrounding land uses include former military
training areas and military housing developments in close proximity to or encroaching upon the
landfill areas, particularly Areas A and F.
The six landfill areas were used for residential and on-base commercial waste disposal. Area A
was used from 1956 to 1966. Areas B through F were operated from 1960 until 1987, when
interim closure of the facility began, effectively terminating waste disposal activities at the 0U2
landfills.
The disposal methods used at Area A are unknown, but are believed to have been similar to
practices used in other areas. Waste received in Areas B through F was placed in shallow,
parallel trenches approximately 30 feet wide, 10 to 15 feet apart, and 10 to 12 feet deep. Waste
was typically placed in the trenches to within two feet of the ground surface and covered with
native dune sand excavated during trenching operations.
Detailed disposal records are not available; however, information gathered during field activities
and from other sources indicates that household and on-base commercial refuse, dried sewage
sludge, construction debris, and small amounts of chemical waste (such as paint, oil, pesticides,
electrical equipment, ink, and epoxy adhesive) were placed in the landfill. Refuse encountered in
the landfill during a test pit investigation conducted by HLA as part of a refuse limits
investigation in 1995 was found to be comprised of domestic waste, construction debris, medical
waste, and miscellaneous waste. Unexploded ordnance (UXO) as well as related training
materials, were reportedly encountered during HLA field activities. These items, gas masks,
barrels, and protective clothing, are believed to be associated with training exercises for mock
chemical warfare material (CWM) attacks. No actual CWNI was found on the landfill during the
previous investigation by HLA.
The background, remedial action objectives, and a summary of the construction schedule
-. associated with closure of the OU2 Landfills are presented below.
SJ16-24-961SACTERCIFTORD 0U21’R.AWP.RV 1
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