Remedial Investigation/Feasibility Study

Remedial Investigation/Feasibility Study, Deer Lodge, MT

KGS performed a remedial investigation (RI)/feasibility study (FS) at the former Deer Lodge Local Training Area (LTA) Munitions Response Site (MRS) in Powell County, Montana (MT) in support of the United States (U.S.) Army Military Munitions Response Program (MMRP) at the request of the State of MT’s Department of Military Affairs Environmental Program. Work was authorized under the USACE Omaha District.

Based on the results of the RI, the informal boundary lines separating the MRS into four investigation areas were removed and new boundaries were drawn to reduce the MRS footprint.

Based on MEC/munitions debris (MD) distribution the RI recommended that the Deer Lodge LTA MRS be split into three separate MRSs:

  • MRS A (3,711 acres). MRS A has three (3) target areas containing the highest density of MD/MEC items.
  • MRS B (5,015 acres). The MRS B area was determined by assessing: the hazardous fragment distance as a buffer around the target areas; significant finds outside the buffers; and draws where significant finds were found to cover the gullies and ridges for those draws where munitions items might have accumulated.
  • MRS C (14,465 acres). MRS C represents locations where no MEC/MD items were located or where only very little MD was found.

The RI confirmed the presence of MEC/MD and their distribution, which reflect a high concentration of MEC/MD in firing fans in the MRS. Following the RI, one data gap remains; right-of-entry (ROE) was not granted on property owned by the Rock Creek Cattle Company; therefore, it is uncertain if MEC items are present on this property. As a result of the presence of MEC/MD, the RI recommended an FS be performed to address MEC. MRS A and MRS B were carried forward into the FS; however, MRS C was not included as it was recommended for no further action. The three (3) MRSs were scored through the DoD MRSPP (32 Code of Federal Regulations [CFR] Part 179). The MRSPP scores were as follows:

  • MRS A: 3
  • MRS B: 3
  • MRS C: 5