Skip Links

USGS - science for a changing world

Scientific Investigations Map 3078

Prepared in cooperation with the

Distribution of Treated-Wastewater Constituents in Pore Water at a Pond-Bottom Reactive Barrier, Cape Cod, Massachusetts

By Timothy D. McCobb, Denis R. LeBlanc, Luke A. Parsons, and Jonathan G. Blount1


1CH2M Hill


Thumbnail of and link to report PDF (10.4 MB)

Ground water contaminated with phosphate (PO4) because of historical land disposal of treated municipal wastewater at the Massachusetts Military Reservation (MMR) is currently (2009) discharging into nearby Ashumet Pond (fig.1; McCobb and others, 2003). Unlike the transport of many contaminants in ground water beneath the MMR, phosphate transport is greatly retarded because it sorbs strongly to the aquifer sediments. Despite the removal of the wastewater source in 1995, phosphate concentrations in the ground water will remain elevated for many decades as natural flushing of the aquifer by uncontaminated ground water results in desorption of this reservoir of sorbed phosphate (Parkhurst and others, 2003).

The potential adverse effect of continued phosphate loading on the ecology of Ashumet Pond has prompted remedial actions by the Air Force Center for Engineering and the Environment (AFCEE). In August 2004, a permeable reactive barrier (PRB) was emplaced on the bottom of Ashumet Pond to reduce phosphate concentrations in ground water discharging to the pond to limit or reverse the adverse ecological effects of the phosphate. In August 2006, the U.S. Geological Survey collected pore-water samples in and near the PRB from depths below, within, and at the top of the barrier. This report presents a series of maps showing constituent concentrations and values of physical properties, layered by depth, as a visual assessment of the effects of the PRB on the geochemistry of the pore water along the shoreline of Ashumet Pond.

First posted October 2009

For additional information contact:
Massachusetts and Rhode Island
Water Science Center
U.S. Geological Survey
10 Bearfoot Road
Northborough, MA 01532

Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.

Suggested citation:

McCobb,T.D., LeBlanc,D.R., Parsons,L.A., and Blount, J.G., 2009, Distribution of treated-wastewater constituents in pore water at a pond-bottom reactive barrier, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Map 3078, 1p.

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Contact USGS
Page Last Modified: Thursday, 01-Dec-2016 17:17:39 EST