By SYDNEY SCHWARTZ
The Patriot Ledger

PEMBROKE - To save Furnace Pond, Pembroke must remove enough muck to fill a football field to a depth of 375 feet.

Experts say that dredging could take up to 22 years and cost more than $20 million.

Comprehensive Environmental Inc., an engineering consultant, presented a study of the muck-filled pond to selectmen on Monday night.

‘‘It’s been an eye-opener and quite an education in less than an hour’s time,’’ Selectman Arthur Boyle said. ‘‘I think having the resources we have ... $20 million is simply out of reach for us.’’

The nearly 110-acre pond is nearly 10 feet deep in the deepest place, but there is almost 17 feet of muck on the bottom in some spots. That has facilitated weed growth - growth that threatens to turn the once-pristine pond into a swamp.

Officials hired Comprehensive Environmental this year to determined how to get rid of the sediment that has accumulated over decades. The town had done two earlier studies of the pond.

The consultant collected and analyzed muck from throughout the pond and found an average water depth of 6.4 feet and an average sediment depth of 7.6 feet.

‘‘It’s just a black, muddy sediment,’’ Curt Busto of Comprehensive Environmental said. ‘‘There’s not a lot of soil or sand mixed into it ... it’s a lot of dead plant debris.’’

The state Department of Environmental Protection puts Furnace Pond in Category 5, the category for the most severely impaired ponds.

The consultant determined that dredging 1.48 million cubic yards of material is the only way to save the pond. The town would need to dispose of the dredged material.

The staging area could be a barge or dock near Mattakeesett Street or Center Street or town land off West Boundary Road or elsewhere, the consultants said.

‘‘Our analysis is worst-case,’’ said Matthew Lundsted, principal of Comprehensive Environmental. ‘‘Once you get over the sticker shock and you decide what you want to do, that’s when you can find those projects that are looking for the material.’’

The 1.48 million cubic yards of dredged material would be pressed to 800,000 cubic yards.

Using some of the material to cap the town’s landfill would only get rid of about 5,400 of the 800,000 cubic yards. Using it on town fields would require mixing it with soil or loam and would add hauling and labor expenses.

On top of all of that, the experts said, the federal, state and local permitting processes take time and money - about two years and $100,000.

Experts recommended applying for permits and dredging a bit at a time, maybe over several decades.

Selectmen said they would ask state Rep. Daniel Webster, R-Hanson, and state Sen. Therese Murray, D-Plymouth, to send a representative to a meeting in August or September for a discussion of funding possibilities.

‘‘If you don’t get rid of the dredge (material) ... it’s decomposing and feeding itself nutrients,’’ Lundsted said. ‘‘You might hold it steady, but nature’s going to continue its course.

‘‘I think there’s a benefit to a limited dredge. Any dredging you can do helps.’’

Sydney Schwartz may be reached at sschwartz@ledger.com .

Copyright 2007 The Patriot Ledger
Transmitted Tuesday, July 17, 2007