Informational displays about groundwater contamination in the area of the former Naval Air Station-Joint Reserve Base Willow Grove adorned the main room of the Horsham Township Community Center at an open house meeting held by the U.S. Navy on Oct. 7.

Members of the public crowded around representatives from the Navy and other agencies, including the Environmental Protection Agency and Horsham Water and Sewer Authority, who were on hand to field questions about environmental issues at the former base, which was formally disestablished in 2011.

According to one of the exhibits at the open house, the facility had been identified as having groundwater contamination as early as 1995. In the years since the base’s closure, the Navy had continued to investigate and clean up the site. While work had been completed at several locations on the former base, the investigation of a number of other portions of the property, including an area used for fire training, have continued.

Meanwhile, the township created the Horsham Land Redevelopment Authority to implement a plan for reuse of 862 acres that the Navy had declared as surplus. The HLRA issued a Request for Proposals in May 2014 to seek a master developer to design, finance, construct and market the mixed-use development of the property in accordance with the authority’s plan. After acquiring the site from the Navy, the HLRA was to sell it to the master developer.

However, at the HLRA’s board meeting in August, Executive Director Michael McGee announced that transfer of the property from the Navy would be delayed because of environmental issues on the site. Under the revised schedule, the first transfer of a portion of the base will not take place until at least next year. The transfer of other areas may not be completed until 2021, after radiological surveys or other investigations have been completed.

“Perfluorinated compounds, including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), have been identified in groundwater and drinking water near the former NASJRB,” the public announcement for the open house explained.

One of the informational displays at the open house identified PFOS and PFOA as manmade compounds used since the 1950s in many products, including firefighting foam. In 2009, the EPA issued a “Provisional Health Advisory Level” for PFOS and PFOA.

“The provisional HAL are reasonable health based hazard concentrations, above which actions should be taken to reduce exposure,” according to the material at the open house.

One of the informational displays indicated that studies on humans had found that “PFOS and/or PFOA may cause elevated cholesterol levels and possibly low infant birth weight,” while animals given large doses of the compounds had been found to “exhibit developmental, reproductive and liver effects.” There also may be a link with certain types of cancer.

The material at the open house indicated that PFOS and PFOA had been detected in groundwater on the base as early as 2011.

Additionally, under an EPA program, public water suppliers such as the HWSA have been required to sample up to 30 types of contaminants that are not currently regulated.

As a result, PFOS and PFOA were detected in several of the authority’s wells. Two wells, containing PFOS at levels above the EPA’s provisional HAL, have been taken offline from the public drinking water system. Three other wells had been found to have PFOS at levels below the provisional HAL.

According to one of the informational displays, the use of firefighting foam on runways, plane crash sites and hangar areas may have been one source of PFOS and PFOA.

The former base’s firefighting training area, which was near Horsham Road, was the likely source of the contamination of one of the two offline wells, located on the opposite side of the road. The other well taken offline is located above Keith Valley Road, next to a sewage treatment plant.

Tina O’Rourke, business manager for the HWSA, said monitoring was underway to establish the location and direction of the groundwater contamination.

At some point, she added, a decision will need to be made about whether the two wells taken offline can be brought back into service. O’Rourke explained that there were options for either containing the groundwater contamination, or else using granular activated carbon filtration to remove any traces of PFOS and PFOA from water pulled into the wells.

Additionally, according to the materials at the open house, private wells near the former base may also contain PFOS or PFOA.

Stephen Jarvela, onsite coordinator with the EPA’s Philadelphia office, said his agency had identified about 220 wells for which it wanted to get permission for taking samples.

As of Oct. 1, he added, over 100 wells had been sampled, and the results were “slowly coming back.” Jarvela estimated that it typically took three or four weeks to get the findings back to residents.

So far, he said, two properties had been identified as exceeding the levels set for PFOS and/or PFOA.

In such situations, bottled water would be provided to residents, Jarvela added. He also said that there were treatment methods for residential wells, and that homeowners had the option of connecting to public water service.

One of the informational displays at the open house pertained to contamination resulting from the release in the 1970s of jet fuel into the ground in the area of what is now the Horsham Air Guard Station. An investigation was completed in 1988, and remedial action, including soil extraction, took place between 1990 and 2011. Quarterly monitoring of ground and surface water is continuing. Clean-up of an off-base parcel is projected to be completed by 2019.