Horsham Water & Sewer Authority




Horsham Water and Sewer Authority Takes 2 Wells Out of Service Due to Detection of Perfluorooctane Sulfonate (PFOS) Above Provisional Health Advisory Level 

Under the Safe Drinking Water Act (SDWA), the Horsham Water and Sewer Authority (The Authority) monitors the quality of water from each of the groundwater wells used to provide your water. We sample as required for substances for which the United States Environmental Protection Agency (EPA) or Pennsylvania Department of Environmental Protection (DEP) have set primary drinking water standards. As we recently reported to you in our annual Consumer Confidence Report (CCR), all of the Authority’s in-service wells produce water into the system that meets the primary drinking water standards.

In addition to routine sampling, the 1996 amendments to the SDWA require that once every five years, the EPA issue a new list of unregulated contaminants to be monitored by public water systems (PWSs). The Unregulated Contaminant Monitoring Rule (UCMR) provides EPA and other interested parties with scientifically valid data on the possible occurrence of non-regulated contaminants in drinking water. These data serve as a primary source of occurrence and exposure information that the agency then uses to develop future regulatory decisions.

On July 30, 2014, the Authority received the first set of results from samples collected for new compounds under the latest round of the Unregulated Contaminant Monitoring Rule (UCMR3). One of the substances detected was Perfluorooctane Sulfonate (PFOS). While further evaluations of this contaminant are performed, EPA has established a Provisional Health Advisory (PHA) level for PFOS of 0.2 micrograms per liter (µg/L). One microgram per liter is equivalent to one part per billion (ppb).

PHA levels serve as guidance designed to assist federal, state and local officials in evaluating threats to public water supplies. Health advisories serve as guidance only and are not enforceable. You can visit EPA’s website for more information about PHA levels at the following webpage:

The provisional health advisories for PFOS and PFOA (Perfluorooctanoic Acid) can be found at:

Two of the Authority supply wells, Well No. 26 and Well No. 40 were recently found to have PFOS above the PHA level (detected at 0.7 ppb and 1.0 ppb respectively). PFOS was also detected in other Authority wells but not above the PHA level. After consulting with DEP, the Authority decided to take Well Nos. 26 and 40 off-line.

PFOS has also been detected at elevated levels in groundwater on the former firefighting training area of the Willow Grove Naval Air Station Joint Reserve Base (“NASJRB” or the “Base”). The Authority’s water source closest to the firefighting training area is Well No. 26. After coordinating with both EPA and the Authority, the Navy collected additional samples at Well Nos. 26 and 40 last week in order to confirm the PFOS levels detected in July 2014.

It is possible that the presence of PFOS in the groundwater is related to historic activities at the Base. The Navy and EPA are working to sample multiple locations both on and off the Base. The impact to the groundwater associated with prior Base operations is part of an ongoing cleanup effort for which regular public meetings through the NASJRB Restoration Advisory
Board are held.

What is being done?
The Authority has voluntarily taken both Well No. 26 and Well No. 40 off-line. The Authority is consulting with state and federal agencies regarding potential sources of contamination. We will keep in regular contact with DEP, EPA, and the Navy to discuss the situation and evaluate possible response actions, including treatment options for these wells.

The Authority has other sources of water which are not affected, and also has the ability to purchase water from neighboring suppliers. The Authority will continually monitor supply and demand in order to determine the possible need for future water conservation measures.

What should you do?
Since the two wells that were impacted by PFOS were taken off-line, you do not need to take any action at your home, office, or school. You do not need to boil your water or provide treatment at your tap. If you have specific health concerns, you should contact your healthcare professional.

What does this mean?
PFOS is one of several perfluorinated compounds that are used, or were once used, in a variety of commercial and consumer products, such as fire-fighting foam, stain and water repellants, paper products, the lining of microwave popcorn bags, floor wax, and non-stick cookware.

PFOS is persistent in the environment and it is estimated by health officials that perfluorinated compounds such as PFOS and PFOA are present in the blood of most people in the United States. In laboratory animals, PFOS can cause developmental, reproductive, and other adverse effects. Studies of exposure to PFOS and adverse health outcomes in humans are inconclusive. EPA is in the process of seeking comments on health effects assessments for PFOS and PFOA. For more information regarding PFOS, you can visit the following EPA webpages:

Please share this information with other people who also receive water from Horsham Water and Sewer Authority who may not have received this notice directly (for example, people in apartments, nursing homes, schools and businesses). You can do this by posting this notice in a public place or distributing copies by hand or mail.

This notice is being sent to you by the Horsham Water and Sewer Authority.

For more information, please contact:
Tina O’Rourke, Business Manager 
(215) 672-8011

PWSID#: 1460033 
Date distributed: August 11, 2014