'Iron barrier' targets pond pollution

 The technique is designed to reduce phosphorus levels in Mashpee's Ashumet Pond.

CAPE COD TIMES
MASSACHUSETTS MILITARY RESERVATION - A federal cleanup will employ an unusual weapon to cut pollution seeping into Ashumet Pond in Mashpee.

The installation of an "iron barrier" will begin Monday, according to officials from the Air Force Center for Environmental Excellence (AFCEE), the agency charged with cleaning up pollution from part of the Upper Cape base - in this case, from its now-closed wastewater treatment plant.

The creation of the barrier may take two weeks, 7 a.m. to 5 p.m., with equipment setup starting at 6:30 a.m.. A silt barrier will be used around the project on the northwest shore of the pond. The boat ramp will remain open at all times at the popular pond.

"As far as our research shows, this will be the nation's first large-scale iron barrier for treating phosphorus in a pond," said program manager Jon Davis of the Installation Restoration Program.

"We are excited that it will help improve the health of Ashumet Pond. The knowledge that will be gained by installing this project will help other communities that are looking to improve the health of their ponds."

The barrier, described at a meeting in June, is the third technique used so far to cut concentrations of phosphorus seeping from the groundwater plume moving into the pond. Too much phosphorus can stimulate the growth of algae and deprive the pond of oxygen.

The barrier will be a 300-by-40-foot mix of excavated pond bottom and iron flakes in a 2-foot-deep section of pond bottom, as permitted by state and federal permits. Phosphorus entering the pond will stick to the iron mixture. The barrier is expected to trap phosphorus for more than 20 years. During the past few years, small areas of the shoreline have been treated with iron on an experimental basis to help develop the larger barrier.

(Published: August 5, 2004)