top of page

SGWASA's Levels for PFOA and PFOS

Updated: Jan 19

On June 15, the US EPA reduced its health advisory levels (“HAL”) for two chemicals - PFOA and PFOS from 70 parts per trillion to interim levels of 0.004 and 0.02 parts per trillion.  SGWASA is committed to adhering to all state and federal water quality standards. SGWASA’s drinking water meets all current State and federal regulatory requirements, and therefore remains safe for consumption.  

The EPA’s interim HALs are guidance and not regulatory requirements.  EPA’s Interim HALs are meant to identify the amount of a chemical a person can be exposed to for their entire life (70 years) without it causing any adverse health impacts.  Results greater than the Health Advisory Levels do not mean that there is an emergency or violation.  Accordingly, exceedances of these interim levels for some period going forward while EPA adopts regulatory requirements and water systems figure out how to meet those requirements, does not mean that public health is at risk or that public drinking water is unsafe.  Click here more information on PFAS.   

What are SGWASA's Levels for PFOA and PFOS? 

Insert here

NC PFAST Quantitative Screening Results for Raw Drinking Water From The North Carolina PFAS Testing Unit


Disclaimer: The PFAS measurements reported here represent initial laboratory findings that have not been subjected to full validation and quality assurance/quality control procedures and should be considered preliminary.

As part of the North Carolina Per and Polyfuoroalkyl Substances Testing (PFAST) Network statewide sampling effort (, a raw water sample collected from SOUTH GRANVILLE WTR&SEWER AUTHORITY (NC0239107) on 2019-06-11 by the Ferguson Lab was analyzed for 47 PFAS chemicals by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Concentrations of individual PFAS are reported in units of parts-per-trillion (ppt, i.e., nanogram of chemical per liter water).

PFAS compounds are not currently regulated as drinking water contaminants by the United States Environmental Protection Agency (US EPA) or the North Carolina Department of Environmental Quality (NC DEQ) and thus the measurements reported here are not intended to be used in enforcement actions. The US EPA has established a lifetime health advisory level (HAL) of 70 ppt for combined perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in drinking water. In addition, the NC DHHS has established a provisional health goal based on risk assessment for GenX in drinking water of 140 ppt. These advisory levels can serve as reference values when evaluating PFAS concentrations reported below for raw drinking water.

Reporting Limit (RL): This is the lowest concentration that can be confidently quantified in water samples for an individual PFAS chemical. This level is a function of instrument sensitivity, reproducibility, and precision. The RL typically (but not always) represents the lowest concentration point on the calibration curve, and it is always higher (often much higher) than the method detection limit (MDL) for a given PFAS analyte.

Sum of PFOS and PFOA

The sum of PFOA and PFOS was 34.3 ppt. This represents 49% of the EPA HAL of 70 ppt for PFOA + PFOS.


GenX was not detected above its reporting limit.

Total PFAS

The total PFAS concentration was 49.4 ppt.

Summary of findings

Figure 1: Concentrations of individual PFAS compounds

Table 1 Concentrations of PFAS compounds detected in parts-per-trillion (ppt). Gray values indicate compounds below the reporting limit (RL). Bold rows indicate occurrence in excess of the EPA Health Advisory Limit (HAL) for PFOS + PFOA of 70 ppt.


Please stay up to date on this topic and other news topics by monitoring our website.

Issued 8/5/22 by the South Granville Water and Sewer Authority

Scott N. Schroyer, Executive Director



Commenting has been turned off.
bottom of page