The last item on the ballots of a third of the Massachusetts districts, including Cambridge's, will be a referendum calling for a moratorium on the construction of nuclear power plants in the state.

Despite its last-place slot in the November election and its non-binding status, the vote could affect nuclear power in Massachusetts -- especially Boston Edison's plans to build a second nuclear plant in Plymouth.

The company's proposed 1,100 megawatt plant -- dubbed Pilgrim II after the 650-megawatt Pilgrim I plant, also in Plymouth -- is pending before the Nuclear Regulatory Commission. No other plants are proposed or under construction in the state.

Boston Edison is not mounting a specific campaign against the referendum but is merely continuing "its ten-year drive to educate the public about nuclear power," a spokesman said yesterday. The spokesman added that despite the $2 billion price tag on Pilgrim II, nuclear power is highly "cost-efficient."

The referendum does not affect either Pilgrim I or the Rowe Yankee plant -- the only other operating plant in the state, Gail Hoffman, a staff member of the Citizens for Participation in Political Action (CPPAX), said yesterday. CPPAX is a political activist group with more than 2000 members working for the referendum.

Over the summer, anti-nuclear groups, including CPPAX and local Clamshell Alliances, formed the Massachusetts Safe Energy Coalition to pool their resources and get the referendum on ballots in as many districts as possible, Hoffman said.

Concentrated Interest

The Coalition needed 1200 signatures in a state senatorial district to get the referendum on the ballot there, Hoffman said. The referendum will appear on ballots in districts by the state's two operating plants and by the northern boundary closest to the plant in Seabrook, N.H.

The referendum will also appear in Boston and Cambridge.

The Coalition is relying on volunteers and the contributions to build support for the issue, Tom Bareiko, coordinator of the Cambridge CPPAX volunteers, said yesterday.

Bareiko said the coalition's budget in Cambridge will be less than $1,000. While the coalition is operating under budgetary constraints statewide, it does have significant political clout.

Longtime supporters of a moratorium on building of nuclear plants include Sen. Edward M. Kennedy '54 (D-Mass.), Lt. Gov. Thomas P. O'Neil III, and Rep. Edward J. Markey (D-Mass).