Tuesday, November 17, 2015

Part 3: Murky Waters, "Capping" Open-Water Sediment Dumps

Corps’ Latest Attempt to Legitimize Open-Lake Dumping of Dredged Sediments

-- third in a series of three --

Rivers and Harbors Act - The authority of the U.S. Army Corps of Engineers (USACE or Corps) to dredge navigation channels in the Great Lakes and elsewhere begins with periodic acts of Congress referred to as the Rivers and Harbors Act of a particular year.  

The Corps is compelled by statute to use the least expensive means in disposing of dredged sediment.  Usually, there are two options for disposal: on-land (or “confined”) and open-water (in our region, a lake).  The least expensive is always open-water, but the catch is that dredged material dumped in a lake isn’t supposed to be contaminated with pollutants.

The eight Great Lakes states (along with two Canadian provinces) have major economic interests in keeping whichever lake or lakes they border clean and healthy.  They have a legitimate concern that any dredgings the Corps wishes to dump off their shores really is uncontaminated.

Cleveland and Toledo - The issue of contamination has been central in ongoing disputes between USACE and the state of Ohio.  In Cleveland, a principal concern has been polychlorinated biphenyls (PCBs).  In Toledo, nutrients from chemical fertilizers and livestock manure in agricultural runoff upstream contaminate dredged river sediments deposited in Lake Erie, fueling toxic algal blooms.

See Open Lake Disposal, a position paper of the Ohio Environmental Council.

Bipartisan Bill to Fund Repairs at Toledo Harbor
                                                       Toledo Harbor                             EPA photo

The Ashtabula Experiment - Earlier this month (November 2, 2015) discussing the Corps’ dredging of Ashtabula (Ohio) Harbor and open-lake disposal, Andrew Kornacki acknowledges on the Defense Video and Imagery Distribution System that “...portions of dredged sediments contain contamination that can have a negative impact on the aquatic environment if not managed properly.”  

In other words, the Corps knows that the dredged material they’re dumping in Lake Erie is contaminated, contrary to the Clean Water Act.  But don’t worry, they’ve come up with a gimmick that might counteract the negative effects.

UPDATE November 21, 2015:  Another article by Andrew Kornacki posted November 20, 2015 states in part,

BUFFALO, N.Y. - The U.S. Army Corps of Engineers (USACE), Buffalo District has released documents that have been submitted to the Ohio Environmental Protection Agency, requesting a Clean Water Act Section 401 water quality certification for open lake placement of dredged sediment from the upper Cuyahoga River federal navigation channel associated with its scheduled 2016 dredging of Cleveland Harbor.

All documents can be found on the Buffalo District’s Web page: http://bit.ly/cleveland-harbor


 Kornacki’s November 2d report says:

Using conventional dredging equipment, the USACE Buffalo District along with the U.S. Army Engineer Research and Development Center (ERDC) have started the first of its kind large scale demonstration of treating dredged sediment, from Ashtabula Harbor, Ohio, with activated carbon to determine if bioaccumulation can be reduced in the bioactive zone of the 50-foot-deep open-lake placement site.

They say the activated carbon is mixed with the dredged sediment on the scow, using a clam-shell bucket.  (Not exactly a Cuisinart blender.)

The project manager is quoted in the report as saying the contamination in the dredged sediment is minimal.  Apparently, we’re supposed to believe that, on the one hand, there’s almost no contamination, but on the other hand, the contamination is so robust that it will justify scientific conclusions about remediation.

Kornacki again:

In a process right from the text book of a high school chemistry class, when the contamination in the sediment comes in contact with the activated carbon the two bond together. The contaminants are so strongly bonded to the activated carbon they cannot be bioaccumulated by aquatic organisms that come into contact with the sediment.

The most biologically active zone in lake sediment is at the surface of the lake bottom. Knowing this, a part of the study is to examine how treated sediment can be used to cap previously placed or existing sediments on the bottom of the lake by placing a 2-5 cm layer of treated sediment to provide a protective bioactive zone.

Wait a minute!  You buried the most biologically active zone, the lake bottom, under thousands of cubic yards of dredgings!  And now you’re going to place (dumping from a scow 50 feet above) a 2-5 cm (one or two inch) carbon-dosed layer of sediment as protection?  Protection of what?  For how long?  Are there no currents in this huge body of water?  Is anybody buying this?

Before USACE is permitted to apply this preposterous idea routinely, its findings and conclusions from the Ashtabula experiment should be subjected to close, scientific scrutiny and replicated by qualified, independent authorities.  The last thing we want in my neck of the woods is open-water disposal in Lake St. Clair.
UPDATE:  Cleveland Plain Dealer by Evan MacDonald, December 19, 2015:                           

"Ohio Attorney General seeks public hearing on Army Corps' proposal to dump dredged material in Lake Erie"

"The attorney general's office has requested a public hearing over the Army Corps' proposal, arguing that the Army Corps 'stands alone in its position that disposing of contaminated sediment in Lake Erie is environmentally acceptable.' "
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