PFAS Water Resources

2y ago
53 Views
2 Downloads
622.49 KB
11 Pages
Last View : 1d ago
Last Download : 2m ago
Upload by : Jacoby Zeller
Transcription

PFAS Water ResourcesCharacterization StudyPer- and Polyfluoroalkyl Substances (PFAS)Surface Water Sampling Results,April 2019 – February 2020Published by thePhiladelphia Water DepartmentNovember 2020Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 2

Executive SummaryThe Philadelphia Water Department began voluntary, proactive testing forper- and polyfluoroalkyl substances, or PFAS, in the city’s rivers and creeks in 2019.The goal was to better understand the occurrence of these compoundsin the city’s water supply.uPWD has not detected concentrations at or above the U.S. EnvironmentalProtection Agency’s health advisory level of 70 ppt (parts per trillion)for two of the most commonly found and widely studied PFAS compoundscalled perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid(PFOA), combined.uSeparate from PWD testing, independent studies led by the EPA and thePennsylvania Department of Environmental Protection indicate nondetectable PFAS concentrations in Philadelphia’s drinking water.The information below details the methodology and results of PWD’s nearly year-long study.Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 3

OverviewPFAS, which stands for per- and polyfluoroalkyl substances, are a broad group of man-made chemicals that have beenwidely used around the world since the mid-20th century to manufacture industrial and consumer products includingcookware, fabrics, furniture, paper goods and firefighting foams. Because they are resistant to heat, oil, and water, theydo not break down easily and can remain in the environment for years.In recent years, these contaminants have gained international attention as they’ve been detected in soil, water, air, andliving organisms including the human body across the world—even in remote locations such as the Arctic. In short, theyare all around us.Research suggests some PFAS compounds may be linked to serious health problems, including an increased risk ofcancer. Yet, despite the everyday use of these chemicals, scientists know relatively little about the health effects of mostPFAS. This emphasizes the universal need for additional research and environmental management strategies. As withmany emerging contaminants, advances in technology used to detect these substances has evolved faster than researchthat can help us better understand the public health effects from these low-level concentrations. Numerous PFASsubstances are currently being studied to fully understand and better regulate these chemicals.In the greater Philadelphia area, PFAS has been detected in groundwater near some military bases that once usedfirefighting foams called AFFF (aqueous film forming foams) that contained PFAS. Philadelphia’s drinking water issourced from the Delaware and Schuylkill rivers, not groundwater. Nevertheless, the existence of these contaminants inwater supplies across the globe means drinking water can be a potential route for exposure.While there are no federal or state drinking water regulations for PFAS in Pennsylvania, in 2016, the U.S. EnvironmentalProtection Agency (EPA) set a health advisory level of 70 parts per trillion for two of the most commonly found andwidely studied PFAS compounds called perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Forcontext, one part per trillion (ppt) is roughly equivalent to one grain of sugar in an Olympic-sized swimming pool. TheEPA guideline is not a regulation, but rather a public health guideline.In 2019, PWD began voluntarily and proactively testing for PFAS in the city’s rivers and creeks to better understand theoccurrence of these compounds in the city’s water supply. This document details the methodology and results of thenearly year-long study. PWD has not detected concentrations at or above the EPA’s health advisory level of 70 ppt(parts per trillion) for PFOA and PFOS combined. Furthermore, results from independent studies led by the EPA andthe Pennsylvania Department of Environmental Protection indicate non-detectable PFAS concentrations inPhiladelphia’s drinking water.Methodology and Sampling LocationsMonthly surface water samples were collected at all three PWD drinking water intakes on the Schuylkill and DelawareRivers and from one location on each of the Wissahickon, Poquessing, and Pennypack Creeks starting in April 2019(Figure 1). These samples were analyzed for PFAS concentrations using EPA Method 537.Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 4

Site IDWISSPENNPOQUDELASCHU1SCHU2Location DescriptionWissahickon Creek at Ft. WashingtonPennypack Creek at Pine Rd.Poquessing Creek at Holy Family UniversityDelaware River at Baxter WTP intakeSchuylkill River at Queen Lane WTP intakeSchuylkill River at Belmont WTP intakeFigure 1. PFAS Watershed Characterization Sampling Site Locations and DescriptionsResults SummarySamples collected from the water treatment plant intake on the Delaware River demonstrated an average combined PFOAand PFOS concentration of 8.1 ppt, ranging from 5.3 to 12.2 ppt. Results from the Schuylkill River water treatment plantintakes exhibited an average combined PFOA and PFOS concentration of 12.1 ppt and 9.7 ppt, respectively, ranging from6.8 to 16.2 ppt.Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 5

Even assuming no removal by conventional water treatment, these results indicate that concentrations in Philadelphia’sdrinking water are far below the EPA lifetime health advisory level of 70 ppt for PFOA and PFOS combined.No surface water sample taken by PWD from any site during this characterization study exceeded the EPA lifetimehealth advisory level of 70 ppt for PFOA and PFOS combined in drinking water (Table 1, Figures 2 and 3). Upstreamtributary locations exhibited higher PFAS concentrations than locations near PWD intakes, primarily due to lower flowsand, consequently, less dilution.Table 1. Combined Concentration of PFOS PFOA Summary (ppt)Location IDDescriptionDELASCHU1SCHU2PENNPOQUDelaware River at Baxter intakeSchuylkill River at Queen Lane intakeSchuylkill River at Belmont intakePennypack Creek at Pine Rd.Poquessing Creek at Holy FamilyUniversityWissahickon Creek at Ft. WashingtonWISSNumber .01120.016.824.0Figure 2. Combined PFOS and PFOA Results for Each Site by Sample Date (ppt)Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 6

The summary statistics from each sampling site are presented as boxplots in Figure 3. Boxplots are useful in looking atthe variability of the data at each site. The end of each line extending from the box indicates that site’s minimum andmaximum normal results value; the majority of each site’s results fall within the range shown by the box itself. Thehorizontal line within each box is the median, or middle, value. The single dots appearing for two sites (PENN and POQU)represent results considered statistical outliers. Tributary sites exhibited greater variability in their results than watertreatment intake sites.Figure 3. Combined PFOS and PFOA results summarized by sampling site (ppt)Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 7

Discussion and ConclusionThe primary goal of the Water Resources Characterization Study is to determine baseline levels of PFAS occurring in thecity’s source waters. Results show that all samples were safely below the 70 ppt EPA health advisory level for PFOSand PFOA combined, with water resource samples taken at PWD intakes being far below this level.It should be noted that the ability to detect the presence of PFAS compounds is advancing faster than the ability tounderstand their public health implications. Advances in analytical methods allow us to detect concentrations in theparts per trillion (ppt) magnitude – the equivalent of one grain of sugar in an Olympic-sized swimming pool. As thescience surrounding PFAS is constantly evolving, we are working to ensure that we are following the latest scientificadvances. We are also collaborating with neighboring water utilities to better understand the influence of regionalgroundwater contamination in the greater Philadelphia area.We continue to voluntarily test Philadelphia’s source waters for PFAS. We will continue to follow public health researchand track both federal and state regulatory developments as this issue evolves so that we can best protect the integrityof our drinking water for generations to come.Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 8

AppendixList of FiguresFigure 1. PFAS Watershed Characterization Sampling Site Locations and Descriptions.5Figure 2. Combined PFOS and PFOA Results for Each Site by Sample Date (ppt).6Figure 3. Combined PFOS and PFOA results summarized by sampling site (ppt).7List of TablesTable 1. Combined Concentration of PFOS PFOA Summary (ppt).6Table 2. Results from grab samples taken from the Delaware River near the Baxter Treatment Plant intake (ppt).10Table 3. Results from grab samples taken from the Schuylkill River near the Queen Lane Treatment Plant intake (ppt).10Table 4. Results from grab samples taken from the Schuylkill River near the Belmont Treatment Plant intake (ppt).10Table 5. Results from grab samples taken from Poquessing Creek at Holy Family University (ppt).11Table 6. Results from grab samples taken from Pennypack Creek at Pine Rd (ppt).11Table 7. Results from grab samples taken from Wissahickon Creek at Fort Washington (ppt) .11Philadelphia Water Department PFAS Water Resources Characterization Study November 2020 9

Table 2. Results from grab samples taken from the Delaware River near the Baxter Treatment Plant intake (ppt)Sampling Date4/22/2019 5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 11/22/2019 FOS PFOA**Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking water1/29/20203.23.46.62/19/20202.62.75.3Table 3. Results from grab samples taken from the Schuylkill River near the Queen Lane Treatment Plant intake (ppt)Sampling Date 4/22/2019 5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 11/22/2019 PFOS PFOA**Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking water1/29/20203.74.98.62/19/20204.86.110.9Table 4. Results from grab samples taken from the Schuylkill River near the Belmont Treatment Plant intake (ppt)Sampling Date 4/22/2019 5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 11/22/2019 4784.55.24.58.410.210.911.412.116.27.68.67.5PFOS PFOA**Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking a Water Department PFAS Water Resources Characterization Study November 2020 10

Sampling DatePFOSPFOAPFOS PFOA*Table 5. Results from grab samples taken from Poquessing Creek at Holy Family University (ppt)4/22/2019 5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 209.18.517.6*Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking waterSampling DatePFOSPFOAPFOS PFOA*4/22/2019171330Table 6. Results from grab samples taken from Pennypack Creek at Pine Rd (ppt)5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 119.7*Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking waterSampling DatePFOSPFOAPFOS PFOA*4/22/2019101121Table 7. Results from grab samples taken from Wissahickon Creek at Fort Washington (ppt)5/28/2019 6/25/2019 7/30/2019 8/26/2019 9/30/2019 10/31/2019 .72418.317.3*Combined for comparison to 70 ppt EPA Health Advisory (May 2016) for treated drinking waterPhiladelphia Water Department PFAS Water Resources Characterization Study November 2020 11

and PFOS concentration of 8.1 ppt, ranging from 5.3 to 12.2 ppt. Results from the Schuylkill River water treatment plant intakes exhibited an average combined PFOA and PFOS concentration of 12.1 ppt and 9.7 ppt, respectively, ranging from 6.8 to 16.2 ppt.

Related Documents:

and far. Human exposure to PFAS in surface waters occurs primarily through use of the waterbody as a drinking water source or through fish consumption. Some PFAS are known to have toxic effects and pose health risks at very low levels. Surface water analysis measures PFAS in parts per trillion (ppt). Fish tissue analysis measures

9 PFAS captures a large class of widely used, long-lasting chemicals used for non-stick, waterproof, stain-resistant, and other uses. PFAS are present in human blood and in the environment and resist being broken down. Exposure to some PFAS is linked to harmful health effects in humans and animals Many PFAS continue to be used, but some -like PFOA and

persistent man-made chemicals. Industry responsibility Companies should immediately work to phase out PFAS chemicals, replacing them with safer, non-PFAS alternatives. Individual action When shopping, ask for and choose PFAS-free products, for example

PFAS-free water PFAS-free sample equipment. 100% cotton clothing (wash 6X no fabric softener) Boots without water proofing. Nitrile gloves. Trip – Equipment Blanks. No Personal Care Products. Tyvek Laboratory Analysis Drinking Water Method 537 Reports 14 compounds. Method 537 – modified

Atmospheric PFAS Transformations: Limited knowledge regarding PFAS atmospheric abiotic reactions and drinking water impacts Elevated concentrations: indoors, near industrial sources, urban areas. Fate and effects are poorly understood: depend on composition, gas-particle partitioning, atmospheric chemistry, water solubility.

State Highway Bridge 199. Bridge (site 9). Water samples were analyzed for PFAS concentrations (Table 4). Two water samples were taken from Lake Worth. One sample was collected at Meandering Creek (site 4) and another at SH 199 Bridge (site 9). Both samples were analyzed for PFAS concentrations (Table 4). Ten PFAS

ual PFAS, we do know enough about the class as a whole to warrant precautionary action. PFAS in drinking water and in consumer products are the focus of increasing concern for businesses, governments, and citizens. In some areas, great strides have been made to eliminate unnecessary uses of PFAS. For example, when KEEN Footwear

AQUEOUS FILM FORMING FOAMS (AFFF) AFFF is a concentrate that is blended with water to create a foam that is intended for fighting high -hazard liquid fires Of most concern are PFAS -containing Class B AFFF Source: ITRC (Interstate Technology & Regulatory Council). 2018. PFAS Fact Sheets PFAS-1. Washington, D.C.: Interstate Technology