Page 10: of Marine Technology Magazine (September 2013)

Leading O A new NOAA report that examines national oil pol- lution threat from shipwrecks has been presented to the U.S. Coast Guard. With as many as 20,000 recorded shipwrecks in NOAA?s database, the May 2013 report  nds that just 36 sunken vessels scattered across the U.S. sea oor could pose an oil pollution threat to the nation?s coastal marine resources. Of those, 17 were rec- ommended for further assessment and potential removal of both fuel oil and oil cargo. Based on vessel contents, condi- tion, environmental sensitivity and other factors, NOAA has determined that six vessels are high priority for a Most Proba- ble (10%) discharge, and 36 are high priority for a Worst Case Discharge (Table ES-1) .NOAA?s Remediation of Underwater Legacy Environmental Threats (RULET) project identi es the location and nature of potential sources of oil pollution. Knowing where these ves- sels are helps oil response planning efforts and may help in the investigation of mystery spills - sightings of oil where a source is not immediately known. In 2010, Congress appro- priated $1 million for NOAA to develop a list of the most signi cant potentially polluting wrecks in U.S. waters, spe- ci cally addressing ecological and socioeconomic resources at risk. Those funds were not intended for oil or vessel re- moval. NOAA maintains the internal Resources and UnderSea Threats (RUST) database of as many as 30,000 sites of sunken material. Initial screening of these shipwrecks revealed 573 that could pose substantial pollution risks. This includes vessels built after 1891, when U.S. vessels began using fuel oil; vessels over 1,000 gross tons and built of steel, and tank vessels. Additional research narrowed that number to 107.To prioritize and determine which vessels are candidates for further evaluation, NOAA used a series of risk factors to as- sess the likelihood of oil remaining onboard, and the potential environmental impact if that oil spills. NOAA used risk fac- tors to assess physical integrity and pollution potential as well as other factors that may impact potential removal operations. Risk factors included total oil volume on board; oil type; if the Oil Pollution Risk Assessment NOAA ID?s Lurking Enviro  reats Category RankNo. Wrecks for Worst Case DischargeNo. Wrecks for Most Probable Discharge High Priority366Medium Priority4036Low Priority 11 45Table ES-1: Number of vessels in each priority category for the 87 priority wrecks. Table 1-1: A sampling of domestic potentially polluting wreck remediation projects.Vessel (Year of Sinking)Project YearLocationActionRemoved (bbl)Oil TypeDepth (ft) Tenyo Maru, 1991 1991WAPartial Removal620Diesel540 Union Faith, 1969 1999LAPartial Removal400HFO125 Ehime Maru, 2001 2001HIPartial Removal665Diesel2,000 Roy A. Jodrey, 1974 2003NYPartial Removal143HFO200 Catala, 1965 2007WARemoval 820HFOSurface William Beaumont, 19712009TXRemoval 380HFO40 Ex- USS Chehalis, 19492010SamoaRemoval1,430Gasoline160 William McAllister, 19632011NYRemoval 5Diesel160 September 201310 MTRMTR #7 (1-17).indd 10MTR #7 (1-17).indd 108/22/2013 9:57:11 AM8/22/2013 9:57:11 AM