Wednesday, July 19, 2017

Can Coal Ash Save the Bay?

Back in the early 1990s Dominion Energy, then Virginia Power, was churning out almost 175,000 tons of coal ash each year in Chesapeake and needed a way to recycle it.

The company would soon discover plenty of ways: Fly ash helped build Harbor Park, the Suffolk Bypass and parts of the Chesapeake Expressway.

But in 1994, a Virginia Power engineer approached some local scientists with a different idea: Using coal ash to build artificial oyster reefs.

It took a few years, but they did it – just one reef.

It still sits today in an inlet of Fisherman Island National Wildlife Refuge, southeast of the last leg of the Chesapeake Bay Bridge-Tunnel. It's owned by the government. A multi-year study found it was just as effective as traditional reef bases, and didn't leach dangerous elements into the water. But dwindling interest from Virginia Power and a lack of funds ultimately killed the project, and no more coal ash reefs were built locally.

But back in the '90s, the engineer's idea appeared mutually beneficial: Scientists could test a new way to help revive the oyster population, and the power company could get rid of the stuff from the Chesapeake Energy Center.

At the time, the Chesapeake Bay oyster population was struggling, said Mark Luckenbach, a marine science professor at the College of William & Mary's Virginia Institute of Marine Sciences. A Virginian-Pilot report from 1994 said the bay was "virtually empty" of oysters.

Marine researchers then, as now, were experimenting with different materials – known as substrates – that could be used to build artificial oyster reefs.

Virginia Power's engineer had seen an experiment from Texas in which coal ash was mixed with cement to form pellets – ranging in size from tennis balls to baseballs – as the base for artificial reefs. The engineer has since retired and Dominion could not find someone to comment on the decades-old project.

 So how did it work out?

The ash bases worked about as effectively as the commonly used shell and granite reefs, the report says. The oysters would be safe for human consumption, according to the report. Most elements in the water were well below the levels of concern for the U.S. Food and Drug Administration.

"Both laboratory and field studies indicate that Virginia Power's stabilized ash is an acceptable substrate for oyster settlement and growth, and has no detrimental effect to either oyster populations or the surrounding environment," the researchers wrote.

Wesson said "everything passed with flying colors as far as safety." Where are all the other coal ash reefs, then?

There are none. After the yearslong test run, Dominion started finding other ways to get rid of the fly ash, such as selling it to builders as construction material, and abandoned the reef project.
So it works fine, and has no environmental side effects. What went wrong? Nothing really; it just wasn't cost effective on the part of the power company. If some group agreed to buy the coal ash and turn it into "oyster nuggets" it would be a good thing. There is a need for suitable substrate for setting and growing oysters in the Bay. Shell has been moved from all over, at significant expense.

Wombat-socho checks in a little late with "Early Morning Rule 5 Monday."

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