Dredging equipment modifications for detection and removal of ordnance
Type:
Presented during:
WODCON XVII: "Dredging in a Sensitive Environment" - 2004, Hamburg, Germany
Authors:
H. Halkola, B. Wild, T. Welp, C. Pollock, V. Dickerson, L. Brown, L. Helms, B. Sugiyama, J.Green
Abstract: The Department of Defense (DoD) is responsible for numerous dredging projects, which in some cases have discovered unexploded ordnance (UXO) within associated sediments. The presence of UXO in dredged material presents a potential explosive hazard to dredging personnel and equipment. Dredged material containing UXO is not acceptable for preferred beneficial use options, including beach replenishment and most upland placement scenarios. However, if UXO can be successfully removed to a high degree of verifiable certainty, then these and other beneficial use and placement options may become viable. This project is a collaborative effort between the US Navy and US Army Corps of Engineers to demonstrate a field-based technology that can separate ordnance from dredged material quickly and effectively while also resulting in a reduction of costs associated with these dredging and placement options. This paper discusses the planning effort for a field-based study to test screening technologies to exclude UXO from the dredged material flow.
This project was planned for three phases. During Phase I, several activities were accomplished during the past year.
(1) A literature search of previous incidences of dredging operations that involved UXO was conducted. Projects reviewed included dredging operations at Toussaint River, Sea Bright, Buckroe Beach, Philadelphia, San Diego in the United States, and internationally in Malaysia, Singapore, Vietnam etc. (2) A flowchart integrating both dredging operations and screening technologies and providing guidance for civil and military dredging operations was designed. Decision paths are based on whether the objective is to remove UXO from the dredge site, the placement site, neither or both. (3) An evaluation of screening technologies was analyzed which were based on visual, mechanical, density, and geophysical screens. (4) An internet-based project repository was created for team members. (5) The project scope and the desired dredging capabilities were narrowed to practical and logical boundaries. (6) Project members traveled to gravel pits and mining sites where practical separation techniques were demonstrated that may be of use at UXO contaminated sites.
During Phase II one or a combination of dredging and separation technologies is proposed to be demonstrated to systematically remove UXO from dredged material safely and effectively. During Phase III a final report with cost metrics, will be prepared. After Phase III is completed, project results will be available on the USACE Dredging Operations Technology Support (DOTS) website at http://www.wes.army.mil/el/dots/dots.html. Current plans are dependent upon funding.
Keywords: unexploded ordnance, UXO, screening technologies, material separation, beneficial use