Warrington Groundwater Wells Update

In the fall of 2014, Warrington Township began shutting down their groundwater wells when PFAS contamination was discovered. North Wales Water Authority purchased the township’s drinking water system in October 2019. After extensive research and communication between the PADEP and Air National Guard, NWWA began the process of constructing and implementing GAC filter tanks at Warrington’s groundwater wells to remove PFAS contamination. At this time, with many water samples collected and water quality assessed, NWWA can turn these groundwater wells back on. Please look at the information below as we endeavor to share all of the work and progress that has gone into making sure these groundwater wells produce water that meets or exceeds all regulatory standards. Note that this information will be updated quarterly as new testing data becomes available. Jump to the Results section.

Important clarification: Warrington customers will continue to receive water from our Forest Park Water treatment facility. NWWA will maintain the water quality so that it continues to meet or exceed all required federal standards. There will be no introduction of primary contaminants for our Warrington Customers. The Warrington distribution system will consist of water from Forest Park and a periodic minor amount from the groundwater wells.

All of the wells, after the removal of all contaminants as required, are to be used for a supplemental and emergency water supply, providing redundancy and security during times of drought, major fire events, main breaks, mechanical failure or power outage at Forest Park Water, and during special operations, such as system flushing. This supplemental supply is intended to help ensure a sufficient and continued supply of safe and clean water to our customers.

‘PFAS’ is the abbreviation for Per- and Polyfluoroalkyl substances. They are a group of many chemicals that are used to create water resistant, fire resistant, oil resistant, and stain resistant. Learn more here.

 

 

The raw water is sent through massive filters filled with granular activated carbon (GAC). The first filter acts as the main treatment vessel, while the second filter acts as a polishing vessel. The result is PFAS-free, finished water.

Granular activated carbon (GAC) is a carbon-based medium used to remove impurities from water. GAC has a highly porous molecular structure with a charge. When waterborne impurities like PFAS come into contact with GAC, its charge attracts and binds them to its abundant surface area.

Carbon filter

After extensive testing and continuous communication with the PADEP, NWWA has determined that the wells are ready to come online. With a populous area like Warrington Township, we need the wells to help supplement water in the distribution system. The wells will also help us during times of drought. Water usage is and has been incredibly high and our area is still under a drought watch.

All of the wells, after the removal of all contaminants as required, are to be used for a supplemental and emergency water supply, providing redundancy and security during times of drought, major fire events, main breaks, mechanical failure or power outage at Forest Park Water, and during special operations, such as system flushing. This supplemental supply is intended to help ensure a sufficient and continued supply of safe and clean water to our customers.

When Warrington Township discovered PFAS in the groundwater wells in 2014-2015, it was determined that the wells would be shut down. Over the next few years, the wells were put on reserve status while we reviewed the various treatment options and discussed our future plan with engineers, PADEP and the Air National Guard. When treatment was finally installed, we began the incredibly involved process of water sampling. Samples were taken from the Raw water, Finished water, and the midpoint to determine the overall water quality. Once the PADEP has determined that the water quality meets all the required drinking water standards, NWWA receives an operational permit to begin using the groundwater wells. At the end of September 2023, NWWA received the necessary operational permits for Warrington wells 3, 5, 8, 9 & 11.

As of October 2023, the Pennsylvania Department of Environmental Protection (PADEP) regulates only two PFAS: Perfluorooctanoic acid (PFOA) with a maximum contaminant level (MCL) of 14 ppt and Perfluorooctanesulfonic acid (PFOS) with an MCL of 18 ppt. It’s important to note that while PFOA and PFOS are the only regulated PFAS currently, PFAS sampling often includes testing for various other PFAS, as indicated in the Results section.

 

Since the construction of the filter systems of each of our wells, we’ve been regularly testing the finished water for PFAS. The current testing schedule for our wells is one PFAS test every quarter—which is reflected in the results section.

‘Raw Water’ refers to water that is pumped straight from the ground before it has received any type of treatment. ‘Finished Water’ refers to water that has been pumped from the ground, sent through both the main and polishing filters, and has been chlorinated. ‘Finished Water’ could also be referred to as ‘Treated Water’.

The midpoint is a sample location located roughly in the middle of the two GAC filter tanks. Sampling from the midpoint gives us a look inside the filter tanks and how well they are removing PFAS. If we start to see PFAS results at the midpoint, that means that the contamination has begun to breakthrough the treatment. It is a “heads up” for us to begin the process of backwashing the filter media or switching our tanks around so that we continue to maintain proper contaminant removal.

‘Ppt’ is a unit of measurement. It is used to measure the concentration of a substance within another substance, like units of PFAS per unit of water. Ppt is roughly equal to one second in a span of 32,000 years or one cent in 10 billion dollars. As a side note, ppt is also referred to as nanograms per liter (ng/L).

A non-detect (ND) result indicates that the instrumentation available cannot reliably measure the PFAS concentration in a sample. As of October 2023, the lowest detectable value for any PFAS in an accredited lab is 2.0 ppt. Consequently, when you encounter an ‘ND’ result, the PFAS value may fall within the range of 0.0-1.9 ppt. With ongoing advancements in technology and a growing understanding of PFAS, the ND threshold is expected to decrease.

Yes, the water is safe to drink. Before the finished water enters the distribution system, we are required to test for many regulated contaminants. In addition, we monitor the quality of the water regularly throughout the distribution system. All of these results are reflected here in our 2022 Annual Water Quality Report for Warrington. You’ll find graphs and tables of our PFAS testing for all the wells in the ‘Results’ section below.

 

 

 

Results

This section features a compilation of all our PFAS testing results from 2019 to 2023. Each subsection is sorted by the well which the data refers to. Each well section features a map of the location of the well and its filtration building. Beside the map is an annual average graph of the raw water PFOA and PFOS results versus an annual average of combined PFOA and PFOS for the finished water from the well (using our most recent test results). For additional data, please click the link below the chart image which will open a PDF in a new tab of the full compilation of data results for each respective well.

Results for Costner wells.

Results for Well 3.
Images for Well 3.

Results for Well 5.
Images for Well 5.

Results for Well 8.
Images for Well 8.

Results for Well 9.
Images for Well 9.

Results for Well 11.
Images for Well 11.


Please call us if you still have questions. We can be reached by email at waterquality@nwwater.com or by phone at 267-482-6940.