On March 18, the USGS Pennsylvania Water Science Center, in cooperation with the Department of Environmental Protection, released data from a 2019 project that sampled surface waters for Per- and Polyfluorinated Alkyl Substances (PFAS)  compounds across Pennsylvania.

The project collected 216 water samples from 178 DEP Water Quality Network station locations in the summer of 2019 analyzing the samples for compounds in the PFAS family of chemicals (of which PFOS+PFOA are a subset).

Raw surface water from rivers and streams was analyzed for PFAS in this study that was intended to understand the occurrence, distribution, and concentrations of PFAS across Pennsylvania, not to assess risk from public drinking water.

The sum of the concentrations of PFOS+PFOA ranged from non-detect to 34 ng/L - or 34 ppt [1 ng/L = 1 ppt].  The EPA health advisory standard for Total PFOS+PFOA is 70 ppt.

The highest concentration of total PFAS(sum of all detected compounds), and PFOS+PFOA were found at the USGS Neshaminy Creek near Langhorne, PA station in Bucks County, a known area of high PFOS+PFOA levels downstream the former Willow Grove Naval Air Station.  Read more here.

The analysis used by the USGS found 10 different PFAS compounds in the sample collected in the Neshaminy Creek Watershed, but the EPA health advisory standard is based only on the PFAS+PFOS in drinking water, not in raw surface water.

Other PFOS+PFOA results included--

-- Valley Creek at Wilson Road near Valley Forge had a result of 25.2 ng/L

-- Wissahickon Creek at Fort Washington had a result of 21 ng/L

-- Delaware River at Marcus Hook had a result of 16.2 ng/L

-- Wissahickon Creek at the mouth in Philadelphia had a result of 15.7 ng/L

-- Connoquenessing Creek near Zelienople had a result of 15.6 ng/L

-- Allegheny River at Kennerdell had a result of 14.8 ng/L

The USGS data release webpage has files available for download with all the sampling data.  The “dataset.1” file has the sample results by location.  A little more than halfway across the spreadsheet a column marked “PFOS+PFOA sum” contains the numbers to compare to the EPA health advisory standard.

The “dataset.1” file in the data release provides data for 33 individual PFAS compounds, 19 PFAS precursors, as well as various sums of PFAS compounds with similar chemical properties or related to certain important groupings (such as PFOS+PFOA).

These results include compounds in the same family of chemicals, but not included in the health advisory number, therefore these combined numbers-- shown in the “dataset.1” file column “Total PFAS sum” will be higher than the “PFOS+PFOA sum” numbers.

For example, the results for the “Total PFAS sum” for the locations above are--

-- Valley Creek at Wilson Road near Valley Forge had a result of 103.3 ng/L

-- Wissahickon Creek at Fort Washington had a result of 94.3 ng/L

-- Delaware River at Marcus Hook had a result of 59 ng/L

-- Wissahickon Creek at the mouth in Philadelphia had a result of  70.8 ng/L

-- Connoquenessing Creek near Zelienople had a result of 49.5 ng/L

-- Allegheny River at Kennerdell had a result of 15.7  ng/L

The USGS and its partners are now doing follow-up monthly sampling at 20 locations that showed higher levels of PFOS+PFOA across the state, according to Joe Duris, USGS PA Water Science Center.

The locations include 10 in the Schuylkill River Watershed, two in the Neshaminy Watershed, one in the Codorus Creek Watershed in York County and seven sites in the Beaver River and Ohio River watersheds near Pittsburgh.

The study also pioneered the use of sampling methodology and equipment cleaning and other techniques used to ensure a “clean” sample was obtained from surface water.

The USGS and its partners will be working on a journal article further evaluating the data, combined with other information about possible sources of PFOS+PFOA in and around the locations sampled, to present a more complete picture of what the data shows, according to Duris.

The sampling data can be found on the USGS PA Water Science Center webpage.  Questions should be directed to Joe Duris, USGS PA Water Science Center, by sending an email to jwduris@usgs.gov or call  717-730-6930.

 Click Here to find the DEP webpage devoted to presenting the same data in several different ways.

Background

On March 12, the Department of Environmental Protection released the second round of Perfluoroalkyl and Polyfluoroalkyl-- PFAS-- testing at 114 public water system locations around the state which found no PFAS at 65 percent of the sites and none of the remaining sites were above federal limits.  Read more here.

In February 2019, DEP determined the federal PFAS standard was inadequate and started the process for developing its own maximum contaminant level.  Read more here.

DEP has contracted with Drexel University to help determine what is a safe level of PFAS chemicals is in drinking water.  DEP expects to present a proposed PFAS MCL to the Environmental Quality Board for action in the fourth quarter of this year.  Read more here.

In February 2020, DEP proposed and took public comments on a groundwater and soil cleanup standard for PFAS chemicals as part of the Land Recycling Program.  Read more here.  DEP expects to present a final version of the regulation to the Environmental Quality Board in the second quarter of this year.  Read more here.

DEP has identified 493 public water system sources as potential sampling sites because they meet the criterion of being located within a half mile of a potential source of PFAS contamination, such as military bases, fire training sites, landfills, and manufacturing facilities.

For more information, visit DEP’s PFAS In PA webpage.

NewsClip:

Jon Hurdle: Critics Push PA To Set Enforceable PFAS Drinking Water Levels To Protect Public Health

Related Article:

-- DEP Issues Discharge Permit With PFAS Limits To Montgomery County Air National Guard Base

-- DEP: 2nd Round Of PFAS Sampling At 114 Public Water System Sites: 65% No PFAS, None Of Sites Above Federal Limits

[Posted: March 25, 2021]

3/29/2021