Daily convoys of coal trucks may soon be rumbling past the rows of fancy expense account restaurants and office buildings on downtown K Street if Chessie System Railroads Inc. succeeds in closing a rail spur that supplies coal for heating the White House and other government buildings.

Chessie told the Interstate Commerce Commission (ICC) this week that it will ask the agency for permission to close the spur, which is primarily used to deliver coal to a General Services Administration (GSA) heating plant. The plant, at 29th and K streets, is used to heat 120 government buildings, including the State Department and Smithsonian Institution, and to provide steam for restaurants, according to Dale Bruce, director of business affairs for GSA's National Capital Region.

Chessie proposes that coal be sent by rail to Bladensburg, transferred to trucks, and hauled into the city via New York Avenue and K Street to the Georgetown plant, federal and city officials said yesterday.

"We generally view K Street as a living disaster already, at least the part of it that goes through Foggy Bottom. If there is a substantial increase in truck traffic we would be opposed" to the plan, said Robert C. Brewster, president of Foggy Bottom Citizens Association.

GSA is considering the Chessie proposal to truck the coal and will base its decision on the efficiency and environmental effects of using trucks, Bruce said.

City officials monitored a four-week test conducted by the railroad last spring, when 32 truckloads of coal a day were sent along the route during a four-week period, said Gene Abbott, a transportation planner with the District's Office of Policy and Planning. On one day, Abbott said, 49 truckloads were driven to Georgetown, enough to supply 13,000 tons of coal a month to the heating plant -- far more than GSA now uses.

City traffic engineers said the coal trucks were "an insignificant addition to the traffic flow" on K Street, he said. "If GSA should demand more coal, it would be an entirely different matter," Abbott added.

"We're doing the best we can to get the railroad to hold a public meeting to present its case to the citizens, so they will have a chance to know what's going on," Abbott said. "Essentially, this is a private enterprise making a private decision, and we have no control over it."

Chessie told the ICC, which must approve closing the rail line, that it intends to file a petition for an exemption from the ICC's normal abandonment procedures, said Louis E. Gitomer, deputy director of the ICC rail section. This is the quickest way to halt rail service, and would take about 90 days, if the commission approves the exemption.

But Lloyd D. Lewis, director of news and community relations for the railroad's parent company, CSX Corp., said there has been no final decision on closing the spur.

He also said that the railroad hasn't decided what to do with the land if service is abandoned.

Several critics suggest that the company wants to get rid of the rail line because the rumbling trains and the noise of coal being dumped at the heating plant is bad for business at the new Washington Harbour hotel and office complex nearby, which is partly owned by CSX.

Concern for its development is a "collateral reason" for pulling up the railroad tracks, said Milton B. Dolinger, a CSX spokesman. "Obviously, the property would be scenically improved" if the trains stopped running.

The main reason Chessie is considering whether to stop rail service, however, is economics, he said. The Georgetown line "doesn't recoup the costs" because it has only two customers -- GSA and a small building supply company in Bethesda, according to Dolinger.

Nonetheless, the railroad's proposal surprised and angered National Park Service officials and residents along much of the wooded right of way, who fear Chessie will sell the land to developers. About a third of the 10-mile stretch of land runs through the C&O Canal National Historic Park.

"We are adamantly opposed to any development. It's outrageous," said George A. Pughe of the Palisades Citizens Association. Owners of homes in the Palisades along the railroad land "bought them for the view" over the Potomac River.

Homeowners believed the property belonged to the National Park Service, which has maintained much of it for years. Most National Park Service officials believed the land would revert to the adjacent landowner, in this case the park agency, if the railroad ever stopped using it, said John Blair, an official with the park unit's capital region. The so-called "reverter clauses" are present in many cases in which the government has given railroads the right to use federal land. But in the case of the Georgetown spur, the Chessie System owns the property outright.

The railroad considered abandoning the Georgetown line in 1983, and in June it gave a required four-month notice that it might ask ICC permission to abandon the service, according to George B. Breznay, a Palisades resident. Palisades homeowners and the National Park Service did not learn of the latest plan until about two weeks ago, according to Blair and citizen association representatives.

GSA officials are in the process of deciding whether they will oppose the abandonment, said Bruce. The agency would register its opinion with the ICC, he added.

The Georgetown plant is running on a stockpile of coal now but will need new supplies by the end of this month, said GSA's Bruce. "We anticipate bringing it in by rail at that time," he said. Chessie has a "common carrier" agreement with the government, which means that it must supply coal indefinitely unless the railroad line is discontinued, he said.

Citizen and environmental groups are pinning some hopes for saving the property from development on a 1983 amendment to the National Trails System Act. The amendment gives "trail user groups," usually a state or county agency, authority to take over abandoned railroad land if they are willing to assume managerial, financial, legal and tax responsibilities and liabilities, said Charles Montange, an attorney for the National Wildlife Federation. The federation believes the ICC is not supposed to approve abandonment if a group can meet these conditions, he said.

Gitomer said the ICC considers the issue unresolved, adding that the amendment is "one of the most confusing statutes I've ever seen."

"We're pretty close" to having the regulations ready to implement the amendment, and expect them to be in force by the end of October, Gitomer said. Asked if he would delay a ruling on an abandonment request if time for a decision came before the regulations were completed, he said, "We'll worry about it at that point in time."

Because the Chessie System owns the land along its Georgetown rail spur outright, officials there "can do with it as they please" if the ICC approves abandonment, Gitomer said.

The Park Service's Blair said, "We're concerned about the impact" that development of the land might have on surrounding property, particularly the C&O Canal park.

Citizen associations in Foggy Bottom, Georgetown and the Palisades are among the most active in the city and will not sit quietly by while coal trucks rumble down K Street and developers build homes along the C&O Canal, warned several association members.

The city can expect a "terrific battle" from the Palisades Citizens Association if it attempts to rezone the land for residential development, said Pughe. "We have had success in the past in opposing rezoning, and we have a healthy budget" to pay for legal advice, he said.