By Anthony Silva, WBZ NewsRadio 1030 New England Business Editor

BOSTON (CBS) – Negotiations continued Thursday between NSTAR and the Utility Workers of America Local 369, as both sides stare down a strike deadline of midnight tomorrow. A federal mediator is taking part in the talks.

Union President Dan Hurley says the talks will go on up to the deadline Friday night, if necessary.

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WBZ NewsRadio 1030’s Anthony Silva reports

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NSTAR is not specifying what issues remain on the table, but Hurley says they are major. He says NSTAR has proposed to shift significant healthcare costs onto the members, adding that NSTAR also wants to eliminate job seniority for workers at the company call center.

Negotiations have been underway for about two months as both sides try to avert a strike this weekend.

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NSTAR says the company continues to negotiate in good faith, and it’s optimistic that an agreement can be reached.