Investigating and Remediating PFAS Contamination: Washington State Department of Ecology Issues Draft Guidance

The Washington State Department of Ecology (“WSDE”) issued a December 2022 document titled:

Draft Guidance for Investigating and Remediating PFAS Contamination in Washington State (“Guidance”)

See Publication No. 22-09-058.

The Guidance states its purpose is to provide direction for investigating and cleaning up Per- and polyfluoroalkyl  (“PFAS”) contamination in Washington State. This is intended to include people remediating contaminated property such as:

• Property owners
• Potentially liable parties
• Cleanup professionals

Further, the Guidance is stated to be applicable to both:

• Formal cleanups (i.e., those supervised or conducted by WSDE)
• Independent cleanups conducted by the property owner on their own or with technical assistance by WSDE

PFAS consist of a large group of man-made chemicals that include perfluorooctanoic acid, perfluorooctane sulfonate, and GenX chemicals. They have been used in various industrial applications and in certain consumer products. PFAS have been described as persistent in the environment and resist degradation.

The WSDE Guidance provides both a general overview of various literature that has been published about PFAS but also details about WSDE specific issues such as:

• PFAS impacts in Washington State
• Regulatory authority under the Model Toxics Control Act
• How WSDE established state action levels for five PFAS compounds
• How WSDE established model Toxics Control Act cleanup levels

Recommendations are also provided for PFAS compounds to analyze for, and factors to consider when evaluating which media should be investigated.

In addition to an introductory chapter, the Guidance contents include:

• Potential Human Health Effects, Groundwater Impacts, and Regulation
• Advisory, Action, and Cleanup Levels, and Historical Investigatory Levels
• Sampling for PFAS Protective Concentrations for Ecological Receptors
• Protective Concentrations for Ecological Receptors
• Treatment Technologies

Appendices include:

• Appendix A: Tables with Supporting Calculations for Human Health Protective Cleanup Levels
• Appendix B: Attachment 1: Surface Water Literature Summary
• Appendix B: Attachment 2: Surface Water References
• Appendix B: Attachment 3: Upland Literature Summary
• Appendix B: Attachment 4: Upland References

A copy of the Guidance can be downloaded here.