Work on 33-turbine wind farm almost completed
November 16, 2011MILLSFIELD — Thirty-three gleaming white 262-foot-tall wind towers, capable of generating a total of 99 megawatts of no-carbon electricity, now dot the ridgelines of Millsfield and Dixville.
Each turbine in the Granite Reliable Power wind farm measures 410 feet from its compact circular concrete base to the tip of one of its three slender-appearing blades. The rotor diameter or "sweep" is 295 feet. The width of the base is 16 feet.
Work on the 3-megwatt (MW) Vestas V90 wind turbines will be completed by the end of the month, explained Site Safety Manager Aubyn Aube of construction contractor RMT, Inc., of Madison, Wisc. Site restoration and landscaping work will continue, however, with aspects undertaken in 2012.
Aube was speaking to a half-dozen visitors on Wednesday's three-hour tour of the project in Dummer and four Unincorporated Places, only two of which — Millsfield and Dixville — host towers. A section of the 34-foot-wide main gravel access road and some underground infrastructure are located in Odell and Erving Location. Although equipment is now being hauled off the site and the workforce diminished, over 250 workers were on site earlier this fall and summer.
"As of today, we've had 243 days without a Lost Time Accident," Aube said proudly, detailing the daily focus that RMT places on safety rules and procedures and sticking to the exact letter of each environmental and regulation, including all the restrictions specified in the Certificate of Site and Facility — the permit issued by the state Site Evaluation Committee (SEC) after a nearly year-long application process.
Approximately 12 miles of new gravel roads were built and 19 miles of existing gravel access roads upgraded, all designed by Horizons Engineering of Littleton.
Wednesday's tour group went to the first of four strings of turbines — the nearly three-mile-long Fishbrook ridgeline on which turbines Nos. 33 to 22 are located. Unlike the Connecticut Lakes, the towers are numbered from north to south.
Wednesday's guests, standing under sunny skies on a large flat cleared space on which a single tower is located, could look north to see the rest of the Fishbrook towers, plus the six turbines — Nos. 21 to 16 — on Owlhead Mountain and some of the eight — Nos. 15 to 8 — on Mt. Kelsey, which rises well over 3,000 feet.
The seven Dixville Peak turbines, Nos. 7 to 1, were out of sight.
Although the towers are located in a seemingly random way, their precise locations were determined from wind data collected over time and their locations painstakingly determined by engineers so as to capture the wind's power, explained Communications Director Julie Smith-Galvin of Brookfield Renewable Power's U. S. Operations. Brookfield, a Canadian energy investment company, owns 75 percent of the project, and Freshet Wind Energy LLC, of Lyme, that is associated with Wagner Timber Management, 25 percent.
The blades will rotate 22 times a minute when the wind blows at speeds from 9 m.p.h. to 55 m.p.h. Right now, before the project is operational, the blades move very slowly in the wind, keeping the gears lubricated.
In a debriefing session at the project's maintenance building at milepost 6 on Dummer Pond Road, located off Route 16, the owner's construction manager Dan Brown discussed the project with entrepreneur Robert "Bob" Shaw of Colebrook, who successfully rebuilt the Pontook Dam on the Androscoggin River to develop a hydroelectric generating station that began operating in December 1986.
Berlin Daily Sun reporter Barbara Tetreault of Berlin recently wrote about the controversial Pontook project, as well as the then-proposed wind farm, in an essay, "Three Grand Schemes," published in the award-winning tome, "Beyond the Notches: Stories of Place in N. H.'s North Country." The dam is now owned by Brookfield, formerly Brascan (Brazil-Canada). In 2002, the company through its Great Lakes Hydro Income Fund purchased six hydro power stations on the Androscoggin River from the then-bankrupt and infamous Pulp and Paper of America.
Brown explained that the tower's rock anchors go deep into the granite, in essence becoming part of the mountain itself. Geologists and geologic engineers carefully examined core samples to find out how far apart the fissures (cracks) in the granite are. "The quality of the granite is excellent," reported Brown. This is why the footprint of concrete in which the bolts were placed can be such a small-diameter circle, he said.
Brown also explained that on-site engineers had walked every foot of the electric line transmission route, on which pole structures — typically 60-feet tall — were erected to take power to the interconnection switching station near Route 16. The original pole placement plan was modified slightly so that there were no even-temporary wetlands impacts. Some flared laminated towers were used to avoid having to place guy wires in wetlands. "We bridged wetlands, after walking the corridor, foot by foot," Brown said.
He praised state Department of Environmental Services (NHDES) Wetlands Bureau inspector Craig Rennie, who is frequently on site, for helping to come up with solutions. "We were able to work through issues with him to avoid environmental impacts," Brown said.
The project is expected to begin commercial operation by year's end. When the wind farm is in operation, it will generate enough clean energy to power over 36,000 New England households.
Long-term power purchase agreements have been signed with both Green Mountain Power and Central Vermont Public Service. Not all its potential generation capacity has spoken for, however, and some will be available on the spot market, Smith-Galvin said.
After undergoing rigorous testing, RMT, Inc., will turn each "turnkey" turbine over to Vestas Operations Group technicians, who will operate the wind farm for two years under a contract with Granite Reliable Power. The project will be monitored and dispatched through Brookfield's state-of-the-art 24/7 control center in Marlborough, Mass.
County treasurer Fred King of Colebrook, who had served earlier as both a state representative and a state senator and subsequently played a key role in promoting the project to the board of county commissioners and the county delegation, said that he is pleased that the wind farm will pay $495,000 a year in Payment of Lieu of Taxes (PILT) to Coös County.
Attorney Jon Frizzell of Colebrook, a member of the Planning Board for the Unincorporated Places, said that the project looks as he had imagined it. He noted that he also had looked at construction activities from the Dixville end when that area was still open to visitors.
Jamie Richardson, a 2006 Dartmouth College graduate who serves as a special assistant for policy in Governor John Lynch's office, was also on hand.
Pip Decker, a 2004 graduate of the College of William and Mary who was responsible for the project's in-state community relations and outreach from 2006 on after he opened an office in the Old Courthouse in Lancaster for then-majority owner Noble Environmental Power of Essex, Conn., was also on hand. When Noble sold its share of the project in Dec. 2010, Decker became a Brookfield employee.
Decker explained that the cleared laydown yard on flat ground, located in Dummer, will be replanted with trees. Earlier, he said, the expanse was crowded with huge turbine parts and construction equipment. The piles of dirt, now covered with erosion-prevention winter mats, will be incorporated into the site's restoration plan. On-site boulders are being moved alongside the gravel roads to mark their edges and protect brook crossings, and the grass seeds scattered on disturbed soil have already sprouted through the hay covering the sloped exposed cuts, required to create a well-graded road.