THE REGION

Oxygen Levels' Impact on Bay Probed

Scientists need to do better at linking low oxygen levels in the Chesapeake Bay to the impact on fish, crabs and other resources, researchers say.

Although the process by which bay water loses oxygen is well known, "it's not clear that we know whether we're making any progress on turning this system around," said Donald Boesch of the University of Maryland Center for Environmental Science.

"We basically have a good idea [that] if we reduce nutrients, oxygen levels will go up," he said. "The big challenge, I would suggest, is how do we know we are accomplishing results, and how do we demonstrate that."

Boesch spoke yesterday as part of a two-day workshop in Adelphi, sponsored by the Maryland Sea Grant college program.

Over the past two years, the area affected by low oxygen levels has increased, and the annual onset has begun earlier.

Low oxygen levels are in a strip of deep water running down the middle of the bay, roughly from the Bay Bridge to below the Potomac River, said Jeff Cornwell, a geochemist at the U-Md. center.

THE DISTRICT

Boy on Bicycle Struck, Killed by Truck

A 13-year-old boy riding a bicycle was killed yesterday after he was struck by a water delivery truck on a busy street in Northwest Washington, police said.

The boy, who was identified as Sheldon Rose, of the 7100 block of Georgia Avenue NW, was riding his bicycle in the block where he lived about 3:15 p.m. when he was hit by the truck, police said.

The truck was making a turn onto Georgia Avenue from Dahlia Street, police said, and its driver told investigators that he did not see the boy. The youth was taken to nearby Walter Reed Army Medical Center, where he died, police said.

MARYLAND

Citizens' Help in Crime-Fighting Sought

Faced with widespread concerns about crime, officials in Prince George's County called yesterday for more citizen involvement to solve the problems.

"You can watch and see and observe and pass on information in a safe way," said Police Chief Melvin C. High. He joined representatives of several of the county's oldest neighborhood watch programs outside the county courthouse to announce details of a new grant program designed to equip the groups.

"The work of all of us is to make sure we don't lose our streets," High said.

The $300,000 grant from the U.S. Justice Department is being administered by police. Citizens groups can apply for grants to help buy cellular telephones, two-way radios, safety vests, flashlights and other equipment. Some of the money will also be used to pay police assigned to work with citizen patrols in some potentially risky neighborhoods.

Head-On Crash Injures Five Teenage Girls

Five teenage girls were injured, two critically, when the vehicles they were riding in crashed into each other in Bowie yesterday morning, Prince George's County authorities said.

Two of the girls were trapped in their gray Buick sedan for a half-hour, and both sustained traumatic injuries, said Mark Brady, spokesman for the county's fire and emergency medical services. The girls were flown to an area hospital, he said, where they remained in critical condition last night.

He said the three other girls, who were riding in a Pontiac minivan on the narrow two-lane road, were taken by ambulance to a hospital with injuries that were not considered life-threatening.

The county police said that although the head-on collision -- which occurred about 9:15 a.m. on Church Road, between Mount Oak Road and Central Avenue -- remains under investigation, the evidence gathered at the scene yesterday indicates that the driver of the Buick may have been speeding.

Swimming Banned Along Antietam Creek

Public health officials have banned swimming along nearly 12 miles of Antietam Creek after a blown fuse at the Hagerstown sewage treatment plant caused 2.7 million gallons of partially treated sewage to enter the stream.

It could be several days to a month before the creek, a Potomac River tributary, is clean enough for safe use, said Kimmy Armstrong, a supervisor for the Washington County Health Department's Division of Environmental Health.

In addition to prohibiting swimming, the Health Department is advising people to avoid fishing, wading and boating on the stream, Armstrong said Monday.

The posted area covers much of the creek's length from Hagerstown to its mouth near Antietam, about 12 miles south.

Because of the release, "anyone is more at risk" of getting ill from the bacteria, which can cause intestinal cramps, diarrhea, nausea and vomiting, Armstrong said.

Terrorism Drill Planned on Patapsco

Officials from Maryland, Baltimore, the FBI and the Coast Guard will conduct a terrorism exercise tomorrow on the Patapsco River, the Maryland Emergency Management Agency announced.

The exercise will include a simulated attack on a large vessel in the Port of Baltimore at the Tyco Telecommunications Fleet Operations Center.

VIRGINIA

Pr. William County Attorney to Resign

Prince William County Attorney Sharon E. Pandak has told supervisors she will resign at the end of the month after 15 years on the job. She offered no explanation and did not reveal future plans, county spokeswoman Liz Bahrns said yesterday.

Pandak, a recognized expert in land use, has received numerous awards for her work.

Fire Damages Building Used by Army

A three-alarm fire damaged a high-rise building in Alexandria last night, the city fire department said.

Roofing materials caught fire about 7 p.m. in a 12-story building occupied by the Army in the 200 block of Stovall Street, a fire department spokeswoman said.

She said that people in the smoke-filled building were evacuated and that damage was estimated at $20,000. The cause of the fire was under investigation.

"We are fighting to preserve both security and freedom, not one or the other. We're not going to accept the closing of the city."

-- Del. Eleanor Holmes Norton (D-D.C.), on the decision to curtail access to major thoroughfares in the District because of terrorism concerns. -- Page A1

Compiled from reports by staff writers Del Quentin Wilber, Jamie Stockwell, Ian Shapira, Michele Clock, Clarence Williams, Martin Weil and the Associated Press.