November 2009 – Permeable Reactive Barrier Intercepts Phosphate in Treated-Wastewater Plume Discharging to Cape Cod Kettle Pond
A permeable reactive barrier composed of sand mixed with zero-valent iron appears to be successfully intercepting phosphate in a treated-wastewater plume prior to its discharge to a kettle pond near the MMR. A new USGS map report uses detailed maps based on temporary well points driven into the barrier to show the decrease in phosphate concentrations as groundwater flows upward through the barrier to the pond. The permanent instrumentation designed and installed to monitor the barrier’s performance is described in a new journal article in Ground Water Monitoring & Remediation. The reduction of the phosphate load to the pond is intended to improve and protect the water quality of the pond.

October 2009 – New Seismic Method Being Used to Refine Bedrock Topography Map for Western Cape Cod
USGS scientists are testing a new method on Cape Cod to measure the thickness of unconsolidated sediments, such as glacial outwash, that overlie crystalline bedrock. The method, referred to as the horizontal-to-vertical spectral ratio seismic method, uses ambient seismic noise, such as microtremors induced by wind, ocean waves, and anthropogenic activity, to estimate sediment thickness and depth to bedrock. Knowledge of the depth to bedrock is critical for the accurate simulation of groundwater flow and contaminant transport in aquifers like the glacial sediments of Cape Cod.

March 2009 – Natural Restoration of Treated-Wastewater Plume Described to New Joint Cleanup Team at the MMR
The natural restoration of the treated-wastewater plume at the USGS Cape Cod Toxics Site was described to the new Joint MMR Cleanup team at its March 2009 meeting. The team provides input to the Dept. of Defense cleanup of groundwater contamination at the MMR resulting from more than 70 years of military operations. The treated-wastewater plume is one of more than 20 plumes being address by the DOD at the military base.

July 2008 – Fate of Contaminant Plumes Near Surface Waters Is Focus of Workshops at USEPA Meeting of National Association of Remedial Project Managers
The discharge of groundwater contaminant plumes to ponds near the MMR was the subject of several presentations by USGS scientist Denis LeBlanc to the 2008 National Association of Remedial Project Managers (NARPM) of the USEPA. The presentations were part of two workshops on recent findings and new methods related to groundwater/surface-water interactions at SuperFund sites. The talks highlighted the use of diffusion sampling to locate volatile organic compounds discharging to surface waters and the fate a phosphate plume discharging to a glacial kettle pond.

August 2007 – USGS and AFCEE Cooperate on Comprehensive Sampling of Treated-Wastewater Plume
The USGS and AFCEE are cooperating this spring and summer to collect groundwater samples from about 310 wells and 54 fifteen-port multilevel samplers in the Ashumet Valley treated-wastewater plume. The plume was formed by land disposal of treated wastewater at the MMR from 1936 to 1995. The samples are being analyzed for major cations and anions, nutrients, trace metals, detergents, and organic compounds. USGS and AFCEE scientists will compare the 2007 data to results from 1978-79, 1983, 1988, 1994, and 1999-2000 to determine how physical, chemical, and microbiological processes are transporting, transforming, and diluting contaminant concentrations in the plume.

June 2007 – Fiber Optics May Help Map Distribution of Groundwater Flow into Pond through Geochemical Barrier
Cape Cod Toxics scientists demonstrated that a new fiber-optic method to measure temperature may be useful to locate groundwater discharge to surface-water bodies. They tested the method at the geochemical barrier installed by AFCEE in 2004 to intercept a phosphate plume discharging to Ashumet Pond. Locations where cold groundwater is discharging to the warm pond water were evident as temperature anomalies along the fiber-optic cable.

April 2007 - LeBlanc Presents the MIT Freeman Lecture
Denis LeBlanc, research hydrologist from the U.S. Geological Survey, presented the 2007 John R. Freeman Lecture at MIT on April 6. The talk, titled "Cape Cod's Billion Dollar Groundwater Cleanup - The Hydrologic Story," was well-attended by a diverse group of environmental professionals from the academic, regulatory, scientific, and consulting communities. The annual Freeman Lecture is sponsored by the Boston Society of Civil Engineers and the MIT Dept. of Civil and Environmental Engineering (http://web.mit.edu/newsoffice/2007/capecodclean.html)

February 2007 - Newly Discovered Lobe of TCE Plume Moving into Toxics Research Area
The Air Force Center for Engineering and the Environment Installation Restoration Program has detected the advance of a TCE plume beneath the wastewater-treatment plant and USGS research well array near the MMR. The plume, which contains TCE concentrations as high as 100 ug/L, appears to be a lobe of the Chemical Spill-10 plume that has bypassed a pump-and-treat capture system. AFCEE is presently evaluating options for containment or treatment of the plume. The USGS is working closely with AFCEE and the regulatory agencies to insure that, to the extent possible, the selected remedial option does not disrupt the natural restoration of the wastewater plume or divert the phosphate plume away from the newly installed geochemical barrier at Ashumet Pond.

December 2006 - IRP and USGS Collect Water-Quality Profiles in CS-10 Plume
The USGS collaborated with the IRP on collection of water-quality profiles and sediment cores from six borings between the abandoned MMR wastewater-disposal site and Ashumet Pond. The borings were drilled in February and December 2006 by the IRP to investigate the Chemical Spill-10 plume. The USGS collected water samples from the borings to look for evidence of the contaminants from the wastewater disposal from about 1935 to 1995. At one site, a USGS geologist examined the sediment cores for evidence of the history of glacial deposition during the last Ice Age.

November 2006 - Students from Johns Hopkins and Tufts Universities Tour MMR Groundwater Sites
USGS hydrologists led a tour of MMR groundwater field sites for 27 students and faculty from Johns Hopkins University and Tufts University on November 3. The sites included an IRP water-treatment plant, a sonic-drilling operation, the USGS research well array, and the treatment system at the Coonamessett River.

November 2006 - Prevalence of Tumors on Bullhead in Cape Cod Ponds Described to Plume Cleanup Team
USGS biologist Paul Baumann described the preliminary findings of a study of the prevalence of tumors on brown bullhead in several Cape Cod ponds to the IRP Plume Cleanup Team on November 8. The results will be described in a future USGS report. The study was funded by the U.S. Environmental Protection Agency.

August 2006 - Monitoring of Phosphate Geochemical Barrier Shows Continuing Phosphate Removal
USGS hydrologists report that field analysis of water samples collected from the geochemical barrier at Ashumet Pond indicate that the barrier continues to remove phosphate from ground water discharging to the pond. The August 2006 sampling took place about 23 months after the barrier was installed by the IRP to reduce phosphate loading from the Ashumet Valley wastewater plume to the pond.