AUGUSTA — A new regional hospital will rise in north Augusta after the proposal won a conditional go-ahead from state regulators Thursday.

A final decision, by the commissioner of the state Department of Health and Human Services, is expected in the next few weeks.

The new MaineGeneral Medical Center will have up to 226 beds and create a regional medical campus next to the Harold Alfond Center for Cancer Care on Old Belgrade Road. The new hospital will combine inpatient services currently offered at MaineGeneral’s Thayer campus and at the Augusta hospital on East Chestnut Street.

“It’s been an eight-year journey,” said Scott Bullock, president and chief executive officer of MaineGeneral Health, the hospital’s parent company. “We’ve stuck to it, and we’re very pleased with the recommendation.”

The state’s Certificate of Need Unit personnel began reviewing the extensive application in December 2009, following a letter of intent that submitted by hospital officials Sept. 29, 2009. After a public notice and a 10-business-day period for public and hospital comment, the unit will forward its recommendation to DHHS Commissioner Brenda Harvey, who has the final say.

According to the application, the regional hospital will cost $312 million to construct and equip, with an additional $10 million in new renovations for the MaineGeneral Medical Center Thayer campus in Waterville.

But the final cost of the entire project will end up nearing $428.5 million with interest on financing costs and adjustments for inflation, according to the application.

Among the conditions imposed on approval, the state wants 34 fewer inpatient beds in the new hospital, and will require it to be fully accessed by Interstate 95 prior to the closing of inpatient operations at Thayer.

Bullock said the reduction in inpatient beds is a significant condition.

“We will work with the department over the next two weeks and hopefully work this out and make sure this is done in the most efficient manner,” Bullock said Thursday. “We’ve done extensive planning and believe it’s in our best interest and the region’s best interest to build the size facility we’ve proposed to build.”

Bullock said the cost to add beds later — as happened at MidCoast Hospital in Brunswick — is significant.

“It costs twice as much to add,” Bullock said. “We’re trying to plan for the future and we think its prudent to build the size facility we propose to build.”

Bullock said the hospital continues to work with the state Department of Transportation to finalize another potential hangup: planning a new I-95 interchange at Exit 113 — at a cost of $11 million.

“We’re close to reaching final agreement on cost-sharing the project,” Bullock said.

Because that project is dependent on federal highway funding, he added: “We appreciate the help we’re getting from (congressional) delegation.”

He said conditions that the interchange be completed before Thayer’s inpatient services are discontinued amount to a significant challenge.

But Bullock said the timing of both the new hospital and interchange projects is fortunate, citing the potential economic impact and the availability of historically low interest rates.

“This project is going to employ hundreds of people in the construction project and will be a most significant development project for the region,” he said.