NOVA SCOTIA rail shippers along Canadian National Railways' Chester subdivision are learning to live with the prospect of abandonment.

Since the CN applied to Canada's National Transportation Agency in June 1988 to abandon its Chester subdivision, the carrier has touted its Laser intermodal service through its Halifax terminal.Instead of giving up rail entirely, shippers can truck product to Halifax to receive rail service, says Gary W. Wendt, CN's senior manager, commercial affairs in Halifax.

Michelin Tires Canada Ltd. of Dorval, Quebec, is one shipper that is exercising this option. Michelin's distribution center in Bedford, Nova Scotia, trucks between eight and 12 trailer loads weekly to Halifax, from where they're piggybacked to Montreal, a source says.

Longtime piggyback shippers, like National Sea Products Ltd. of Halifax, say Laser's introduction has improved service. National Sea has been shipping ''a couple of trailers each week," a company traffic official says.

But not all shippers are making the transition. The impending abandonment has reduced rail shipments of Bowater Mersey Paper Co.

The Liverpool, Nova Scotia-based paper supplier now is shipping only eight railcars a week because customers are worried, says a company official. "We were doing about 24 cars a week a year ago, but many of our receivers are choosing truck now," the official says.

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MEANWHILE, CP RAIL, WHICH JUST RECEIVED early approval from the NTA to halt service on its Dominion Atlantic Railway, has given assurances of continued service to the line's biggest shipper.

Fundy Gyspum Inc. of Windsor, Nova Scotia, received a verbal commitment that service will continue when the CP halts operations between Coldbrook and Yarmouth on the Dominion Atlantic, says John Fitzgerald, Fundy's traffic manager.

Fundy, which supplies 90 percent of Dominion Atlantic's revenue, ships five trains of 21 cars a day of raw crushed gypsum from Windsor to the docks at Hantsport.

"In the summer, it'll be four trains a day of 25 cars, so the volume will be about the same," says a source at Fundy's Mill Creek plant.

Traffic is so sparse on the Kentworth-Yarmouth route that the CP operates just one train a month, says Barry Scott, a CP spokesman.

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THE ADMINISTRATION'S LONG-AWAITED National Transportation Policy report will be released soon and there's something in it to disappoint practically everybody.

Government printing presses are busy running off copies of the report. But copies floating around Washington indicate that if this is a blueprint for the 21st century, Armageddon is just around the corner.

For example, the report will call for truckers to pay more to finance highway construction and maintenance programs. Except for some ideas for toll road financing, the Department of Transportation leaves it to states and

localities to come up with the money.

Railroads also will be required to pay more money to finance government safety programs, though the DOT does call for Congress to consider changes in the Railway Labor Act or to repeal the Federal Employees Liability Act.

There will be increases in user fees, spelled t-a-x-e-s, levied on passengers and cargo, in the report. Most of these, however, were outlined in the budget.

All in all, the report seems to be much ado about nothing and far less than what the government claimed it would be in the first place.