Soundings - Winter 2014 - (Page 16)

FEATURE NOAA'S RULET PROJECT ASSESSES RISK FROM SHIPWRECKS By Lisa C. Symons, Damage Assessment and Resource Protection Coordinator, NOAA Office of National Marine Sanctuaries A merica's coastal waters are home to more than 20,000 sunken ships, and 10,000 other potentially polluting threats, including airplanes, munitions, dumpsites and abandoned well heads. However, a series of so-called "mystery spills" in the late 1990s - sightings of oil where a source is not immediately known or suspected -- brought the realization that these largely forgotten wrecks posed some risk to the nation's coastal economies and marine environments on which many communities depend. In 2010, Congress appropriated $1 million for the National Oceanic and Atmospheric Administration (NOAA) to determine which of those 20,000 wrecks were the most significant potential pollution threats. In May 2013, NOAA completed an iterative, multi-disciplinary process and delivered the Risk Assessment for Potentially Polluting Wrecks, a national assessment of the most significant potentially polluting wrecks in US waters to the US Coast Guard. The report, part of NOAA's Remediation of Underwater Legacy Environmental Threats (RULET) project, identifies the location and nature of potential sources of oil pollution from sunken vessels and helps oil response planning efforts. This report was accompanied by risk assessments for 87 specific wrecks. These risk assessments include historical information, an archaeological assessment, probabilistic pollution trajectories and the associated Worst Case and Most Probable (10%) Discharge ecological and socio-economic resources at-risk information. In working through this process, NOAA reviewed more than 30,000 unique targets in US waters listed in the Resources and UnderSea Threats or RUST database. This internal database developed an initial inventory of both historically significant resources as well as sites that could be a threat to marine and coastal resources in national marine sanctuaries. The project 16 * Soundings WINTER 2014 soon grew beyond the scope of the National Marine Sanctuary System but eventually honed in on 87 vessels that merited individual risk assessments. An iterative narrowing of criteria and extensive research helped to narrow the number of vessels that should be modeled for potential pollution impacts to socio-economic and ecological resources. The probabilistic pollution modeling was possible for all 87 vessels due to resource constraints. Some vessels were grouped by generalized oil type and geography. For each wreck and spill volume, the model was run 200 times for 30 days, with each individual run starting on a randomly-selected date/time, thereby sampling the potential environmental conditions that could occur during a release. The models were run for five different spill volumes (100%, 50%, 10%, 1% and .01%). The model outputs provided information to evaluate both the probability and the consequences for ecological and socio-economic impacts from a wreck that would impact the water column, the water surface and/or the shoreline. As a general rule, the threshold for socioeconomic impacts is much lower than the ecological thresholds. At the request of the Coast Guard, each risk assessment addresses both a conservative worst case discharge (the maximum amount

Table of Contents for the Digital Edition of Soundings - Winter 2014

ASA President’s Report
Moving the Unmovable COSTA CONCORDIA – the Largest Wreck Removal Ever Undertaken
Nontank Vessel Response Plan Requirements for Salvage and Marine Firefi ghting Services
When will Responder Immunity Legislation be Enacted?
NOAA’s RULET Project Assesses Risk from Shipwrecks
Meet the ASA Membership
In the News ASA Elects New Leadership National Maritime Salvage Conference Brings Together Maritime Stakeholders
Events & Announcements

Soundings - Winter 2014