Under recently proposed legislation, trucking could become an undercover activity in the nation's capital.

D.C. Council member Jim Nathanson (D-Ward 3) has introduced a bill requiring that loose cargo must be covered and restrained in any vehicle traveling in the city. The bill, which sets a $500 fine for violators, is under consideration by the council's Committee on Public Works, headed by Nadine Winter (D-Ward 6). Winter and six other council members are cosponsors of the measure.

"What I hope it will do is stop the trash, dirt, litter and little stones that bounce off trucks and through the streets, and cause cracks and holes" in autos, Nathanson said. He also sees it as a means of preventing large objects from striking vehicles and proving a menace to motorists.

"I just saw a mattress on Rock Creek Parkway. I'm presuming that it fell off a vehicle, and that someone didn't carry it down and leave it on the road," Nathanson said.

Fewer than 20 states have statutes regulating vehicle covers, according to Tom Kozlowski of the National Highway Traffic Safety Administration. Of those, the regulations vary widely: Wisconsin requires covers only for explosive materials, while neighboring Minnesota mandates lids only on livestock.

Neither the safety administration nor the Insurance Institute for Highway Safety maintains statistics on accidents attributed to the fall of debris from moving trucks.

But Anne Renshaw, who lives on what she calls "the speedway portion" of Military Road near 29th Street NW, said that rubbish ranging from clouds of dust to a spear-tipped piece of stockade fence have flown into her yard from passing trucks, which have increased in number since the city began an overhaul of Military Road.

Betty August, managing director of the Washington D.C. Area Trucking Association, a 100-member industry group, said that the industry's main concern regarding truck cover legislation is the cost of tarpaulins and of possible workers' compensation claims or liability suits from drivers who might fall while covering their loads.

"It's not common, but there's always the possibility that {a driver} could be up there and lose his footing," she said.

These arguments are among those used successfully by the trucking lobby in Maryland, where the state legislature has debated and eventually defeated several truck cover proposals since the early 1960s.

This week, the Montgomery County Council holds public hearings on a measure introduced by William E. Hanna Jr. that would require covers on trucks using county roads.

"The first person scheduled to testify is a man whose daughter was killed when a mattress flew off a truck and hit her car," said Merle Steiner, Hanna's legislative aide. When the council announced the bill, "we got all kinds of wrenching letters" reporting refuse-related accidents, she said.

Ray Ashworth, executive vice president of the Virginia Trucking Association, said that he expects that a proposal for truck covers will come up again this year in the Virginia General Assembly. The current law requires that contents must not drop, sift, leak or escape from trucks, but makes no stipulation that the load be covered.

Norman Grimm, traffic safety manager for the American Automobile Association's Potomac chapter, said that such a law is virtually useless in controlling spillage because "there has to be a police officer there to issue a ticket" at the precise moment a rock or log or stream of ash flies off a truck.

"The threat of getting caught is not there," Grimm said. A covered truck law, by contrast, could be far more easily enforced simply because an officer could spot a cover at a glance.

Grimm also said that in Maryland, Virginia and the District, 97 percent of AAA members surveyed supported such legislation.

"I just can't believe that legislators aren't ready to make the commitment, when it's something the people clearly want," he said. "Legislators are telling them they're wrong. They're not ready to do it yet."