Formerly Used Defense Sites
NAFTAN ORDNANCE DISPOSAL / NAFTAN BOMB STORAGE
NOD/NBS: Remedial Investigation/Feasibility Study
The U.S. Army Corps of Engineers (USACE) conducted a nationwide effort to identify, manage, and prioritize future response actions at Formerly Used Defense Sites (FUDS). Two sites included in this Program are the 604-acre Naftan Bomb Storage (NBS) site and the 9-acre Naftan Ordnance Disposal (NOD) munitions response site (MRS). Site Inspection (SI) field efforts were previously conducted in June 2012 and March 2013, respectively, and consisted of instrument-aided qualitative reconnaissance and munitions constituent (MC) environmental sampling. The objective of the SI was to evaluate the likelihood and significance of the potential residual presence of munitions and explosives of concern (MEC) and associated MC. A Remedial Investigation/Feasibility Study (RI/FS), the next phase of the process, was recommended for both MRSs to assess the nature and extent of identified MEC and MC contaminant concerns.
An RI/FS was initiated in 2015 and the results will provide the foundation for the Proposed Plan and Decision Document used to document the evaluation and selection of an appropriate Remedial Action (RA) at each MRS. Following approval for and completion of the RA, a Recurring Review process will be implemented to ensure the selected remedy remains protective of human health and the environment.
The U.S. invasion of Saipan, part of Operation FORAGER, began on 15 June 1944, lasting three weeks after which the island was declared officially secured by U.S. forces. Under Japanese rule since WWI, Saipan was deemed strategically significant to the U.S. due to proximity of the Japanese mainland (<1300 miles) and within striking distance of new long-range B-29 Superfortress bombers as well as a point of departure for a planned large Allied land invasion. On June 15, 1944 U.S. Marines landed on Saipan and quickly secured the primary Japanese airfield, Aslito Field, and refurbished it to support B-29 aircraft, renaming it Isely (Isley) Field. In support of the objective, extensive bomb and munitions storage facilities and revetments were constructed on the Naftan Peninsula, adjacent to the airfield.
The bomb storage area was described as located east of runways A and B at Isley Field (now Saipan International Airport) and extending south to Naftan Point. This area, the northern portion of the NBS MRS, stored air-to-ground and incendiary munitions used by the 73rd Bomb Wing during its bombing and incendiary raids over Japan. Additionally, three pre-invasion Japanese gun emplacements and ammunition storage areas are located within the NBS MRS. The smaller NOD MRS, located at the southern tip of the Naftan Peninsula, was not documented for munitions storage use but instead specifically for disposal of damaged or surplus U.S. ordnance. The munitions were bulldozed from the Naftan Peninsula plateau into a ravine and covered with thermite/thermate bomblets which were detonated to destroy the surplus munitions by fire.
The southern portion of the NBS MRS, as well as the entire 9-acre NOD MRS, was formerly designated by the CNMI Department of Natural Resources as a wildlife area (Naftan Wildlife Area) in 1978 as part of Saipan’s becoming a Commonwealth. This designation was officially rescinded in 1992 to allow for anticipated development of a large-scale golf resort across much of the area. However, construction was halted due to ordnance presence. A formal Site Survey was conducted in 1995. Approximately 180 500-lb bombs, 1000 2-lb incendiary bombs, and 60 3- and 4-inch projectiles were burned/detonated as part of the “Naftan Point Detonation Project.” These findings were consistent with historical accounts that the NBS and NOD MRSs were, in part, used for the disposal and abandonment of the extensive stockpiles of surplus munitions by both detonation and burning for many years after cessation of wartime hostilities. Most of the property comprising both MRSs is currently under the purview of the CNMI DPL and is characterized as undeveloped jungle. Smaller ownerships include approximately 40 forested acres under the jurisdiction of the CNMI Ports Authority, 27 heavily disturbed acres within the fenced Hawaiian Rock Products quarry operation, and 18 contiguous privately-owned acres.
Both the NBS and NOD MRS were identified as eligible for inclusion in the DERP FUDS Program following confirmation of MD and MEC from assorted U.S. munitions in varying stages of decay (to include burned/melted). Larger items to include detonated 500- lb and 1000-lb bombs and incendiary bomblets were noted specifically in the NBS MRS. The presence of surface munitions was observed during the SI.
The RI/FS was conducted to characterize the nature and extent of MEC at both the 604-acre NBS MRS and the 9-acre NOD MRS and will be used to evaluate viable and cost-effective remedial options as part of the pending FS. The fieldwork was completed in two phases between January 2016 and August 2016 and included digital geophysical mapping (DGM) to identify subsurface metallic anomalies for intrusive investigation as well as MC sampling. The presence and extent of both surface and subsurface MEC was documented throughout both MRSs. One hundred forty-two hazardous MEC items were recovered from within the NBS MRS; 118 on the surface. In addition, three of the surface MEC included intact 500lb incendiary bombs near the Hawaiian Rock facility. Elevated MC contaminants detected during the SI were further evaluated confirming concentrations of antimony, barium, copper, lead and zinc in soil above either human health or ecological risk levels. For the NOD MRS, soil samples resulted in similar contaminants as observed in the NBS MRS. A total of 54 MEC items were recovered during intrusive investigations to include 22 on the surface.
Public involvement is an important and critical part of the RI/FS activities. A Community Relations Plan was developed in an effort to reach out to local interested parties and keep them informed of the project activities. Public Meetings have been held periodically. Any members of the public who would like to remain apprised of the progress of the project should plan to attend the public meetings as well as visit the project Administrative Record maintained at:
Joeten-Kiyu Public Library (www.marianaslibrary.org)
Beach Road and Insatto Street
Saipan, MP 96950 (670) 235-7322
Administrative Record Contact: Erlinda C. Naputi
For More Information
The USACE wants the public to be a part of study efforts as we work hard to ensure the public’s safety, the safety of our onsite workers, and to protect the environment. For more information about the FUDS MMRP and the Naftan MRSs RI/FS project, contact the USACE Honolulu District (Ms. Helene Takemoto) at 808-835-4088 or E-mail: FUDS-POH@usace.army.mil (Source: USACE)
If you should find an object you suspect may be ordnance, DO NOT TOUCH IT! Remember the Three R’s:
1. RECOGNIZE – Be aware that the object may be dangerous;
2. RETREAT – Move away from the object and do not touch it; and
3. REPORT - Call 911 or local police department immediately.
Last Updated 12/15/2017 3:41:54 PM