[Exclusive] Scientists Correct Ballast Water Treatment Report

A group of scientists have written a letter to Regina McCarthy, the Administrator for the U.S. Environmental Protection Agency, telling her that they have made a mistake. The letter aims to correct what they see as an erroneous conclusion in "Efficacy of Ballast Water Treatment Systems," a report by the EPA Science Advisory Board (SAB).

The scientists were members of the 2010/11 Science Advisory Board Panel that drafted the report at the request of the EPA Office of Water and the U.S. Coast Guard, who used it to develop the Coast Guard's ballast water discharge standards implementing the National Invasive Species Act and the EPA's ballast water discharge standards in the Vessel General Permit.

“We are writing to inform you that one of our report's main conclusions is incorrect. Our report concluded, based on available test data, that five types of shipboard treatment had demonstrated the ability to meet a set of ballast water discharge standards known as the IMO D-2 standards (also referred to as the USCG Phase 1 standards), but that no types of shipboard treatment had demonstrated the ability to meet standards 10 times more stringent. 

“However, we recently re-examined the test data on which this conclusion was based, and using the method of assessment described in the report found, to the contrary, that some treatment types had demonstrated the ability to meet discharge standards that are at least 10 times, and in some cases nearly 100 times, more stringent than the IMO D-2 standards.”

The findings are important because in adopting discharge standards identical to the IMO D-2 standards, both the U.S. Coast Guard and the EPA cited the Science Advisory Board report as the basis for their conclusion that these "represent the most stringent standards" that ballast water treatment can "currently safely, effectively, credibly, and reliably meet."

“SAB's admission of the incorrect analysis and their correction, is good news for the shipping industry,” says Dr Rob Hilliard, invasive species specialist and principal at Intermarine Consulting. “Especially to those who have been voicing their concern that many currently type approved systems might need to be completely replaced, rather than just re-tested by the vendor and perhaps tweaked a bit so as to achieve a future, higher U.S. discharge standard. 

Hilliard continues: “It is also good news to five of those 15 ballast water treatment system manufacturers who had chosen independent labs and testing regimes for their IMO type approval that surpassed the basics of G8. In doing so, they have provided sufficient output data for the SAB to review in their report to EPA. Another interesting feature is that the five units covered a range of technology: filtration with chlorine dioxide, filtration with electro-chlorination, and filtration with PeraClean. In another words, a range of treatment approaches.”

Jad Mouawad, a ballast water treatment system specialist and principal at Mouawad Consulting, agrees with the authors of the letter that some treatment technologies have demonstrated, in the confined setup of land-based tests, that they can meet discharge standards that are much more stringent than that of the IMO D-2 Standard.

“However, we have to keep in mind that this equipment will be applied in the confines of a ship. The engineering as well as operational aspects of treatment of ballast water must weigh in to the standard we can realistically expect those equipment to achieve.

“Onboard ships, which Professor Cohen constantly seems to ignore, things are dirty and they get contaminated. The D-2 standard is already too stringent to be met realistically onboard ships. This is why I always call for Port State Controls to take it easy on ships the first 10 years to see how well we can manage to meet the D-2 standard (not because equipment don´t work, but because ships get contaminated and polluted).

“Suggesting anything near more stringent standards is uttermost ignorance on the realities of ballast water treatment onboard ships.”

The letter is expected to encourage the U.S. Coast Guard to move forward with its examination of a Phase 2 more stringent standard for ballast water treatment system discharge.

The scientists that signed the letter are:
•    Dr. Andrew N. Cohen, Director, Center for Research on Aquatic Bioinvasions
•    Dr. Fred C. Dobbs, Professor of Ocean, Earth and Atmospheric Sciences, College of Sciences, Old Dominion University
•    Dr. Robert Diaz, Professor Emeritus, Department of Biological Sciences, Virginia Institute of Marine Science
•    Dr. Peter M. Chapman, Principal, Chapema Environmental Strategies 
•    Dr. JoAnn Burkholder, William Neal Reynolds Distinguished Professor, Director, Center for Applied Aquatic Ecology North Carolina State University
•    Dr. Loveday Conquest, Professor Emeritus, School of Aquatic and Fishery Sciences, University of Washington