The Southeastern Public Service Authority now looks certain to continue past 2018, when its initial agreements with its eight member communities will expire.

Seven of the eight communities, including Suffolk, have signed on to continue cooperating for their trash disposal. Portsmouth remains the outlier and is expected to make a decision by mid-June.

“I think it’s a very just and fair agreement,” SPSA board chairman Marley Woodall said in Wednesday’s meeting. “This is an example of what regionalism is.”

The full board voted Wednesday to authorize SPSA staff to sign the agreements the other seven member communities — Suffolk, Franklin, Southampton County, Isle of Wight County, Chesapeake, Norfolk and Virginia Beach — have approved. It also voted to approve a final agreement with RePower, a company that plans to provide a waste disposal system for the authority’s members.

David Arnold, a local attorney who represents Suffolk on the board, and William Sorrentino, who represents Virginia Beach, voted against authorizing the agreement with RePower.

“I believe that RePower is an unproven technology,” Sorrentino said.

He worried about whether RePower will stick to the agreement and the legal repercussions if it were to fail.

“I feel confident they will come back and ask for changes,” he said, adding SPSA could face a lawsuit if the plant doesn’t work. “Nobody’s going to put money into a plant that fails and not pursue litigation.

“If you vote yes, you’re voting on a hope,” he concluded.

RePower plans to build a plant in Chesapeake that would convert some of the region’s trash into energy pellets, which the company says could be used as an alternative fuel source to coal.

The authority currently ships trash collected at the curbside from local residents to the Wheelabrator plant in Portsmouth, which incinerates it and produces steam, from which energy is made to power Norfolk Naval Station and sell onto the grid. Wheelabrator was passed over in favor of RePower to continue providing disposal service past 2018.

Suffolk City Manager Patrick Roberts, who previously had voted against issuing the intent to award to RePower, said his concerns about the Suffolk landfill being a backup plan have been mitigated by provisions in the host agreement and use and support agreement.

He also said he’s been advised the risks to communities and taxpayers of legal action arising from the RePower plant are “minimal or nonexistent.”

Portsmouth City Council has deferred a vote on its future membership in SPSA until June 14. It issued a request for proposals for a waste disposal system in case it decides to strike out on its own.

“The council is looking at all of its options in terms of whether or not SPSA is presenting the best deal in terms of going with RePower versus whatever may be out there under an RFP,” Cheran Cordell, senior deputy city attorney for Portsmouth, said during a Portsmouth City Council work session on Tuesday.

Proposals are due in response to Portsmouth’s request on June 1.