Cal. Health & Safety Code § 116378
(c)
(3) For perfluoroalkyl substances and polyfluoroalkyl substances with response levels where detected levels of a substance exceed the response level, a community water system or a nontransient noncommunity public water system shall take a water source where detected levels exceed the response level out of use or provide public notification within 30 days of the confirmed detection. For the purposes of this paragraph, notice shall be provided as follows:
(A) A community water system shall do the following:
(iv) Use one or more of the following methods to reach persons not likely to be reached by the notice provided in clause (i):
(B) A nontransient noncommunity water system shall do both of the following:
(ii) Use one or more of the following methods to reach persons not likely to be reached by the notice provided in clause (i):
(C) A notice shall contain all of the following information:
(vii) If a non-English speaking group other than a Spanish-speaking group exceeds 1,000 residents or 10 percent of the residents served by the water system, either of the following:
(D) The following requirements apply to a notice provided by a water system: