D.C. health inspectors say they have identified the source of a mysterious stench that drifted through the city recently: the Washington Suburban Sanitary Commission.

The WSSC dumped sewer waste for several months in a field at its pumping station in Capitol Heights, health inspectors said in a report issued yesterday. The report said WSSC officials told inspectors that the waste included "roots, gravel and cigarette butts, human personal items and a variety of other objects that are normally found within the sewer system."

WSSC officials disputed having a link to the odors that generated hundreds of complaints from D.C. residents. In an interview, they said that the agency had dumped only a small amount of material and that it was not responsible for the smell.

"There was not enough [waste] to create the widespread odors," said Al Richardson, a commission spokesman. "It doesn't support the argument for the widespread gas odor problem."

Richardson said the commission no longer would dump waste at the site because it was not a "good business practice." He said the decision was not made in reaction to the District's health report.

For weeks, D.C. authorities had been trying to pin down the source of the stench, which was first noticed Sept. 28. Fire officials received more than 30 calls about gas leaks that day, primarily at large public buildings across Northeast Washington.

Scores of others called Washington Gas to report leaks. Residents said the smell reminded them of rotten eggs, propane, methane and skunks. Two schools were evacuated, and some residents and students complained of headaches and nausea.

Fire officials initially blamed the odor on a sewer leak in Capitol Heights or storm drains that had not been flushed by rainwater in several weeks. WSSC officials said at the time that the sewer leak was not to blame.

D.C. health inspectors were led Friday to the WSSC pumping facility just across the Maryland border in the 1700 block of Kenilworth Avenue by a bystander who spotted "gaseous sewer effluent" being poured onto the field by a WSSC pump truck, the report states.

During their visit, the report states, the inspectors noticed a "methane sewer-type odor."

Jim Sillers, a WSSC employee, told the inspectors that the waste had been extracted from sewer collection systems in Maryland and was dumped at the facility daily.

In an interview yesterday, Sillers denied telling the inspectors that the waste was dumped every day.

"Less than a pickup truck load" of waste was deposited on the field, he said. "I didn't notice any strong odor."

Officials at the Maryland Department of the Environment said inspectors will visit the site in coming days to ensure that it complies with regulations and a July consent decree.

Under the decree, reached with state and federal environmental regulators and the U.S. Justice Department, the commission agreed to improve sewer treatment systems and plans to prevent sewage overflows into waterways.

Richard McIntire, a spokesman for the Environment Department, said inspectors had visited the Capitol Heights area when they received complaints about the odor in September and October. But they had been unable to determine the source, he said. The department could issue warnings or fines if the WSSC is found to have improperly dumped waste, he said.

D.C. Council member Carol Schwartz (R-At Large), who held a hearing on the issue Oct. 6 and pushed city officials to find the source, said she was relieved by the report's findings.

"It's appalling," Schwartz said. "I'm just glad the situation is now rectified. I'm relieved that the odor, while certainly troublesome, was not caused by something truly hazardous."

Staff writer Nia-Malika Henderson contributed to this report.