The fourth snowstorm in a week buried the Western Maryland counties of Garrett and Allegany under more than 30 inches of snow yesterday, shutting down all but essential businesses and leaving road conditions hazardous if not impassible.

In Cumberland Mayor F. Perry Smith declared a state of emergency snow-removal equipment to help out in clearing clogged city streets.

National Guardsmen were called out to be a standby for any rescue to other emergency operations. I'm 60 years old and this is the most snow I've ever seen." said George Dunlap, a dispatcher for Allegany County Civil Defense, which was coordinating snow emergency operations.

In both Garrett and Allegany counties last night, state police were urging motorists to avoid all but essential travel.

Most interstate and state highways were reported open, but in many spots there was room only for one-way travel. County roads were blocked completely in many locations.

In both Oakland and Cumberland, most stores and businesses were shut down and schools, libraries and municipal and county offices closed.

In Garrett, Maryland's westernmost county, chief dispatcher Dan Rumer of the sheriff's office said stranded motorists were being picked up by sheriff's deputies and taken to nearby motels to wait the storm out.

In Cumberland, Marvin Stewart, a personnel representive for United Parcel Service, checked out of the Holiday Inn yesterday morning, prepared for a 105-mile drive to his hoae in Fairmont, W. Va.

"I heard what the state police were saying on the radio," Stewart said. "I knew I had to go over the mountains on Rte. 48 and there aren't many rest stops and only a few houses. "I checked back in and I'll try gain tomorrow."

Stewart said his activities for the day consisted of having lunch and walking around in Cumberland. "There wasn't much to do, because most of the stores were closed," he said.

Dare Crowner, an announcer for radio station WCMD in Cumberland, went off duty Thursday shortly after 11 p.m. He left the station intending to drive himself home, but then thought better of it and spent the night at the station.

Some Western Marylanders had no qualms about venturing out in the storm. "There's no problem out here. We've got all the right equipment, snow tires and all that. We know how to drive in the winter," said Ted Lascaris, a motel clerk in Garrett County.