Port’s water quality also challenged

NORTH CHARLESTON — Water pollution at the Port of Charleston is another concern that has landed state regulators in court with environmental groups.

In South Carolina, dredging is not supposed to be allowed if the work sucks a lot of oxygen from a river. But state regulators are allowing a $900 million port expansion to lower oxygen levels on one stretch of the Cooper River, environmentalists charge.

The Department of Health and Environmental Control’s decision in 2006 to issue a water quality permit to the State Ports Authority caused environmentalists to appeal. They say DHEC violated state water quality rules in approving the expansion in late 2006 and early 2007.

It’s one of two major legal disputes between DHEC and the S.C. Coastal Conservation League over expansion of the port. The league also says the port expansion will pollute the air and violate federal air quality rules.

The water fight focuses on a spot in the Cooper River where ships will dock at the old Charleston Naval Base. Oxygen levels in that area will drop by more than the amount legally allowed after the river channel is dredged, the Conservation League charges. The area is about the size of 78 football fields.

“I was just dumbfounded by that when I found out,’’ said Blan Holman, an attorney who is challenging DHEC permits for the Conservation League.

State water quality standards say dissolved oxygen can’t be lowered by more than one-tenth of a milligram per liter on rivers with naturally low dissolved oxygen levels, such as the Cooper. In this case, dredging is expected to lower oxygen levels by two-tenths of milligram per liter.

Holman, with the Southern Environmental Law Center in Charleston, said the water quality violations mean the agency can’t legally permit the port. State coastal law says the agency can’t approve a permit for a port that violates state water or air quality standards, he said.

DHEC acknowledges oxygen levels in the Cooper River will drop in that area, but officials say the change won’t affect most of the river. For that reason, DHEC contends the project won’t violate S.C. water quality standards.

DHEC officials declined to comment extensively because of the Conservation League’s legal challenge to the permits.