While the Ex-ORISKANY fish data clearly shows contamination of the food chain from the sinking of ships in shallow waters as artificial reefs, the Navy has long claimed that deep water sinkings conducted through SINKEX do not pose the same contamination risks to the food chain. Below therefore it is necessary to explore the validity of this claim.
Current SINKEX remediation practices were developed 11 years ago (1999) and were based on the Sunken Vessel Study that assessed the impacts of a single SINKEX vessel, the Ex-USS AGERHOLM, 16 years after the vessel’s 1982 sinking. At the time of the assessment, solid PCBs were not believed to leach into the marine environment and little was known about PCB transport in the marine environment. This study was conducted by the Navy itself, a
beneficiaries of ocean dumping allowances, and therefore had good reason to present a case that served their interest. Several follow-up studies including the Modeling Study in March 1994, and the PCB leachability laboratory study based on sediment samples were conducted to verify the Navy’s initial conclusions, but again, these studies were conducted by the Navy. In fact, the Navy’s conclusions have gone unchallenged for over a decade, until now.
As discussed in the Legal Framework section, the EPA allowed SINKEX to operate solely under the General Permit (issued under the Marine Protection, Research and Sanctuaries Act) and exempt from TSCA, because there was a “lack of evidence of unreasonable risk to human health or the environment..." considering the type of PCB material involved
They stated, “Solid PCBs are not
believed to be readily leachable to the marine environment.”40 These conclusions are not
Official letter from Carol Browner, EPA Administrator, to Richard Danzig, Secretary of the Navy, September 13, 1999 IBID. 39 40
BASEL ACTION NETWORK
supported by current scientific research as solid PCBs are now known to readily leach into the marine environment as documented in the Navy’s own solid PCB leach rate studies.41 However, the Ex-ORISKANY post-sinking fish data confirms solid PCBs leach more rapidly into the marine environment than the Navy’s simulated leach rate estimates and are taken up through the food chain more rapidly than the
Further, the Navy has long argued that PCB releases in the deep ocean from SINKEX vessels (6,000 feet or greater) do not pose adverse risks to marine life at that depth. The Navy has also suggested that the deep benthic environment has minimal chance of physical or biological transport to the shallow marine ecosystem.
physicochemical properties of PCBs, including
concentration factor, and very low degradation
environment.43 And hydrophobic (readily
because PCBs are very come out of solution),
persistent and highly lipophilic lipids and organic carbon) they
(partition into readily adsorb
particles and thus readily build up in chain (bio- and geo-accumulation).44
Investigation of PCB Release-Rates from Selected Shipboard Solid Materials Under Laboratory-Simulated Shallow Ocean (Artificial Reef) Environment; April 2006. http://www.spawar.navy.mil/sti/publications/pubs/tr/1936/tr1936c ond.pdf 41
ORISKANY Post-sinking Monitoring Study 3 ! year progress report, 2006-2009 42
Mackay, D., W.Y. Shiu, and K.C. Ma, 1992. Illustrated handbook of physical-chemical properties and environmental fate for organic chemicals, Vol. I, Monoaromatic Hydrocarbons, Chlorobenzens, and PCBs. Lewis Publishers, Boca Raton, FL, 697pp. 43
Froescheis, Oliver, Ralf Looser, Gregor M. Cailliet, Walter M. Jarman and Karlheinz Ballschmiter, 2000. The deep-sea as a final global sink of semivolatile persistent organic pollutants? Part I: PCBs in surface and deep-sea dwelling fish of the North and South Atlantic and the Monterey Bay Canyon (California), 44