This chapter directs the Division of Public Health to make available online to the public the levels of PFAS, also known as “forever chemicals,” in public drinking water systems in this State. This chapter also requires water utility companies in this State to notify public drinking water system users if the PFAS in those users’ drinking water systems exceed a certain maximum contaminant level of PFAS.

85 Del. Laws, c. 220, § 1; 

As used in this chapter:

(1) “Division” means the Division of Public Health.

(2) “Hazard index” means a sum of fractions in which each fraction compares the level of each PFAS measured in the water to the highest level below which there is no risk of health effects.

(3) “Maximum contaminant level” or “MCL” means the legal threshold limit on the amount of a substance that is allowed in a public water drinking system.

a. Except as provided under paragraph (3)b. of this section, the MCLs for the PFAS regulated under this chapter are as follows:

1. For PFOA, an MCL of 4.0 PPT.

2. For PFOS, an MCL of 4.0 PPT.

3. PFHxS, an MCL of 10 PPT.

4. For PFNA, an MCL of 10 PPT.

5. For HFPO-DA, commonly known as “GenX chemicals,” an MCL of 10 PPT.

6. For mixtures containing 2 or more of PFHxS, PFNA, HFPO-DA, or PFBS, a hazard index MCL of 1.

b. If the United States Environmental Protection Agency (“EPA”) establishes an MCL that is lower than the MCL for a substance under paragraph (3)a. of this section, the MCL established by the EPA for that substance is the MCL for this chapter.

(4) “Perfluoroalkyl and polyfluoroalkyl substances” or “PFAS” means per- and polyfluoroalkyl chemicals, substances, or compounds, which are substances with at least 1 per-fluorinated methyl group (-CF3) or 1 per-fluorinated methylene group (-CF2-), including parents, salts, and anionic forms. For purposes of this chapter, PFAS includes only those PFAS with an established legally-enforceable “MCL,” as defined under of this section.

(5) “PPT” means parts per trillion.

(6) “Public drinking water system” means as defined in § 6002 of Title 7.

85 Del. Laws, c. 220, § 1; 

(a) The Division shall develop and maintain a user-friendly website that the public may access to find the level of PFAS in each public drinking water system in this State. The website must meet all of the following requirements:

(1) Be accessible using a prominently-displayed link on the home page of the Office of Drinking Water’s website.

(2) Include a chart or a link to a chart showing the MCL thresholds so that users can see how their public drinking water system’s PFAS levels compare to the MCLs.

(3) Include PFAS levels for every public drinking water system, to the extent that such information is available to the Division. Where PFAS levels are not available to the Division, the website must indicate the approximate date on which PFAS levels will be available online and must post the PFAS levels online as soon as they are available.

(b) If, while monitoring PFAS for purposes of compliance with this chapter, the Division finds PFAS in a public drinking water system that exceed the MCLs, the Division must promptly notify the water utility company in charge of the affected public drinking water system.

(c) Upon receiving notification from the Division that a PFAS MCL has been exceeded in a public drinking water system, the water utility company that operates that public drinking water system must provide prompt notice of the excess PFAS levels to all Delaware residents who receive water from that system.

(d) The notice under subsection (c) of this section must meet all of the following requirements:

(1) Be sent through the U.S. Postal Service to the address at which the resident is receiving the water from the public drinking water system.

(2) Include a brochure that the Division shall develop that explains PFAS and includes a chart showing the MCLs.

(3) Inform the resident that PFAS in excess of the MCLs have been detected in the resident’s water supply.

(4) Provide the exact level of each PFAS chemical that exceeds the MCLs.

85 Del. Laws, c. 220, § 1;