By Denise Emsley, Naval Facilities Engineering Command Hawaii
PEARL HARBOR-HICKAM (NNS) -- The Navy received a new State Emergency Hazardous Waste Permit from the State Department of Health (DOH), Oct. 5, allowing the future treatment of waste military munitions by detonation at a specific site on Waipio Peninsula for 90 calendar days.
"Our contractors have successfully managed the screening and destruction of military munitions recovered from a cleanup project of past dredged material from Pearl Harbor," said Navy Region Hawaii Environmental Program Director Aaron Poentis. "The waste munitions continue to be collected in a safe, secured location at the Navy's Confined Disposal Facility, Waipio Peninsula, Joint Base Pearl Harbor-Hickam."
This year's work was initiated in May 2015 with the first DOH permit issued in June 2015.
Approximately 40,000 cubic yards of dredged material has been sifted and over 2,000 munitions items plus numerous small arms ammunitions have been recovered. Sixty-three detonation events have occurred which has safely destroyed 1,919 munitions items plus numerous small arms ammunition. Types of items destroyed include 5-inch projectile, 4.5-inch barrage rockets and/or motors, 3-inch projectile, 75mm projectile, 60mm mortar, 40mm projectiles and/or casings, 37mm projectile and/or casings, 20mm projectiles and/or casings, grenades, practice bomb, TNT demo charge, bulk explosives, fuzes, flares, a revolver and various small arms ammunition.
"The new permit will allow the Navy and its contractors, Cape Environmental Management Inc., and USA Environmental, to move forward and avoid delays with the screening and destruction of recovered munitions over the next 90 days," said Poentis. "Detonation events will be conducted in accordance with the respective Work Plan, Health and Safety Plan, Explosives Safety Submission and applicable Standard Operating Procedures."
Munitions that are found during screening of dredged material are collected and safely stored in secured portable magazines until a detonation event is scheduled for their destruction.
All future detonations will be scheduled as needed and occur during a normal business week, Monday - Friday, 8 a.m. - 5 p.m. at the pre-designated, secure location at Waipio Peninsula. Indication of detonation work may be a series of "popping" sounds that could be carried on the wind and heard by the public. At no time will the public be at risk.
As required by the DOH permit, a notice for the public regarding the issuance of this 90-day permit was placed in the Honolulu Advertiser on Sunday, Sept. 27.
DOH initially granted the Navy a State Emergency Hazardous Waste Permit on June 29, allowing the treatment of identified waste military munitions by detonation at a specific site on Waipio Peninsula for 90 calendar days from the issuance of the permit. A maximum of 50 detonation events were allowed by the permit. An additional 20 detonation events to a maximum of 70 detonation events were authorized by DOH Aug. 20. Each controlled detonation event used no more than 15 pounds net explosive weight. The new permit allows a maximum of 90 denotation events with each having the same limit of 15 pounds of net explosive weight.
Contractor personnel performing this work are trained and have implemented various controls and safety precautions to ensure safety of personnel and protection of the environment.
Initially this project began in April 2013. The contractor, Cape Environmental Management, Inc., screened construction and dredged material for munitions and some that were recovered were treated on site by controlled intentional detonations on Oct. 30, 2013. Due to lower than expected productivity, the project was temporarily suspended. After re-evaluating the process and making improvements to increase productivity, the project recently resumed in May 2015. Work is estimated to continue through the Spring/Summer 2016.
Due to past historical events--e.g., Dec. 7, 1941 attack, May 1944 Landing Ship Tank explosion, suspected past disposal practices, etc.--some munitions are suspected to be in waters of Pearl Harbor. During construction and maintenance dredging, munitions have been removed along with the dredged material. Dredged material has been temporarily accumulated within earth-bermed cells on Waipio Peninsula to be dewatered, dried and screened prior to use for other beneficial purposes--e.g., landfill soil cover, etc.
"Everything has gone according to plan and we expect that future work will continue to be unobtrusive to the public," said Poentis. "This announcement is to keep everyone informed so if unfamiliar noises are heard from this activity, no one is surprised."