(Bloomberg News) General Electric Co. must resume dredging New York's upper Hudson River for contaminants under a plan that aims to release fewer toxic-laden sediments into the water, the U.S. Environmental Protection Agency said.

Rules released today for the second phase of the cleanup require GE to be more efficient in the way it dredges the river bottom, the agency said in a statement. Judith Enck, EPA administrator for the region that includes New York, will announce the cleanup requirements today.

GE in 2009 lost a court case challenging a 2002 EPA order to dredge pollutants, including PCBs, that its factories in Hudson Falls and Fort Edward dumped into the river for three decades beginning in the 1940's. In August 2009, dredging by Fairfield, Connecticut-based GE was temporarily suspended when tests showed PCB levels were exceeding EPA standards.

"The plan for Phase 2 calls for constant evaluation of new data, and provides for adjustments as the project moves forward if needed," according to the EPA statement. These improvements "will ensure that the momentum of the cleanup work in the river continues and that the biggest sources of ongoing contamination are addressed."

GE must improve sampling to get more accurate information on the extent of contamination, the EPA said. The maker of power-generation equipment also must dredge deeper in certain areas and in most cases limit to two the number of dredge passes.

EPA Limits

Multiple dredge passes in 2009 left areas open for months, allowing exposed sediments to return to the water, the EPA said. The EPA also will limit capping, a technique in which heavy sediments are anchored to the river bottom to hold toxins in the soil, to 11 percent of the project area. In the first phase, 22 percent of the total acreage was capped.

"We're negotiating the particulars and I just don't want to give a specific value," to the cost, GE Chief Executive Officer Jeffrey Immelt told reporters after his annual shareholder meeting with investors on Dec. 14. "The dialogue is quite constructive. It's always our intention to complete the dredging project. We just want to do a dredging project that makes sense and can be executed."

PCB, or polychlorinated biphenyl, is an industrial compound that resists chemical and biological breakdown, and scientists consider it a likely human carcinogen. Before being banned in 1977, PCB was commonly used in fluids in transformers and electrical equipment, as well as an additive in adhesives, plastic and paint.

The EPA says that GE discharged as much as 1.3 million pounds of PCBs into the Hudson River from 1947 to 1977.

The company agreed in October 2005 to remove the PCBs along the 40-mile stretch of the river near Albany, even as it challenged the law in court. The EPA originally estimated the entire cleanup will cost as much as $750 million over six years.