Voters in this college town are considering a crackdown on polystyrene coffee cups and other food containers made of long-lasting plastic foams.

The proposal was expected to come before the 350-year-old institution of the Town Meeting on Monday in the community of 35,000 people.The aim of the ban is to discourage the use of plastics because they are not easily biodegradable, take up considerable space in the town dump, and release gases that deplete the Earth's ozone layer when they are manufactured and burned, according to sponsor Cynthia Pauley.

But a spokeswoman for the Polystyrene Packaging Council, a trade group in Washington D.C., disputed those claims, saying researchers have found that fast-food packaging takes up only one-quarter of 1 percent of landfills by weight and volume.

Spokeswoman Betsy DeCampos said the polystyrene industry voluntarily agreed to stop using chlorofluoromethane in the manufacture of plastic cups by January out of concern for the ozone layer.

And DeCampos contended that plastic is not the only material that takes a long time to decompose. "There are newspapers that are 50 years old that are still intact and readable," she said.

Several communities from Oregon to Florida are considering bans on polystyrene cups. Bans already are in effect in Berkeley, Calif., and Suffolk County, N.Y., on Long Island. This summer, Massachusetts Gov. Michael S. Dukakis issued an executive order banning state agencies from purchasing plastic foam food packaging; the ban goes into effect in July, Pauley said.

However, Pauley said backers of the Amherst law would be satisfied with a six-month study of the problem, a measure that the selectmen are expected to propose.