BENNINGTON - A new boiler plant at Southwestern Vermont Medical Center cleared local permitting this week, but state regulators still need to sign off on the project. Development Review Board members on Tuesday approved the site plan for a new central heating plant, a $3.75 million project that SVMC officials estimate would save $200,000 a year and lower the hospital's carbon emissions. Oil-fired boilers would be replaced with more efficient units that burn natural gas, with the option to someday use biomass and wood, according to plans filed with the state. SVMC has applied for a "certificate of need" from the Green Mountain Care Board (GMCB), the state's health care regulatory board, which must approve major healthcare projects. The board held a public hearing in Montpelier on Oct. 27 that a handful of hospital officials attended, according to the board's website. According to documents filed with the GMCB, the hospital's central utility plant now uses three oil-fired boilers that provide hot water, as well as steam to heat buildings and sterilize medical equipment. The boilers have a 20-year lifespan, but are all over 30-years-old. And the number 6 fuel oil they burn is "outdated, inefficient and polluting." The oil boilers would be decommissioned and replaced with three new, efficient models that would use compressed natural gas, or number 2 fuel oil as a backup. Two units would be 400 horsepower. One would be a 500 horsepower "convertible" boiler, which could be modified to burn biomass. The boilers and related infrastructure would be housed in a new, 3,610-squarefoot prefabricated metal structure on the north end of the hospital campus, to the east of an existing maintenance building and some 200 yards from patient care areas. That building is designed to house equipment related to biomass, and truck deliveries, according to a presentation made by SVMC officials and on the GMCB website. Two 20,000 gallon underground fuel oil tanks would be removed. The project also calls for installing a compressed natural gas decompression station, a 20,000 gallon above ground number 2 fuel oil storage tank, and about 200 yards of steam pipes. A previous hospital administration also pursued a boiler replacement: Officials announced in 2008 they would build a central utility plant with three oil-fired boilers, a generator and other infrastructure, estimated at $11 million. The project received GMCB and Act 250 approval, but was put on hold when the hospital ran into financial difficulties in 2009. That project led the Bennington County Regional Commission and the Bennington Energy Committee to question whether the hospital explored alternative energy, primarily biomass and wood. SVMC had to complete a feasibility study under a condition of the Act 250 permit, but hospital officials decided against use of alternative energy and said a wood-fired systems would be too costly. The latest project drew similar comments. The regional commission, on behalf of the energy committee, offered comments around alternative energy use and benefits of biomass. So did the state Department of Public Service and nonprofit organization Renewable Energy Vermont, which were granted "amicus curiae," or "friend of the court," status. Last December, SVMC officials requested a temporary hold on their application and said they would engage with the three entities. In June, hospital officials submitted a revised application with plans that could accommodate biomass. Reach Edward Damon at 802-447-7567, ext. 111 or @edamon_banner.