(a) If no potable water wells are located within one-half mile beyond the boundary of a municipal setting designation, the executive director shall not require a person addressing environmental impacts for a property located in the municipal setting designation to:
(1) investigate the nature and extent of contamination in groundwater except to satisfy the requirements of Subsection (b); or
(2) conduct response actions to remove, decontaminate, or control environmental impacts to groundwater based solely on potential potable water use.
(b) Notwithstanding Subsection (a), the executive director shall require a responsible person to complete a response action to address environmental impacts to groundwater in a certified municipal setting designation if action is necessary to ensure:
(1) the protection of humans from exposures to environmental impacts to groundwater that are not related to a potable water use, including exposures from nonconsumptive uses and exposures resulting from inadvertent contact with contaminated groundwater; or
(2) the protection of ecological resources.

(c) If potable water wells are located within one-half mile beyond the boundary of a municipal setting designation, the executive director shall require a person addressing environmental impacts for a property located in the municipal setting designation to complete an investigation to determine whether groundwater contamination emanating from the property has caused or is reasonably anticipated to cause applicable human health or ecological standards to be exceeded in the area located within one-half mile beyond the boundary of the certified municipal setting designation.
(d) If an investigation described in Subsection (c) confirms that groundwater emanating from the property has not caused and is not reasonably anticipated to cause applicable human health or ecological standards to be exceeded in the area located within one-half mile beyond the boundary of the certified municipal setting designation, the executive director shall approve the completion of groundwater response actions at the property except to the extent that response actions are necessary to satisfy Subsection (b).
(e) If an investigation described in Subsection (c) confirms that groundwater emanating from the property has caused or is reasonably anticipated to cause applicable human health or ecological standards to be exceeded in the area located within one-half mile beyond the boundary of the certified municipal setting designation, the executive director shall approve the completion of groundwater response action at the source property if the person addressing environmental impacts:
(1) completes response actions at the source property to remove, decontaminate, or control environmental impacts to groundwater to meet applicable human health or ecological standards; or
(2) completes response actions at the source property to remove, decontaminate, or control environmental impacts to groundwater that are not related to a potable water use, including actions to protect humans from exposures from nonconsumptive uses and exposures resulting from inadvertent contact with contaminated groundwater and actions to protect ecological resources, and:
(A) provides to owners of impacted potable water wells described in Subsection (c) a reliable alternate water supply that will provide a volume of water sufficient for the intended use for a period not shorter than the period that the impacted wells exceed the human health or ecological standards and, after obtaining permission from such owners, files a restrictive covenant that prohibits the use of groundwater from those wells as potable water and restricts other uses of groundwater in a manner consistent with groundwater quality; or
(B) expands the municipal setting designation in accordance with the procedures under this subchapter relating to the initial application for a municipal setting designation to include the properties with impacted potable water wells described in Subsection (c).
(f) Notwithstanding any other provision of this section, the executive director may require a person responsible for property within a certified municipal setting designation to complete a response action to address environmental impacts to groundwater emanating from the property that has caused or is reasonably anticipated to cause applicable human health or ecological standards to be exceeded in an area located more than one-half mile beyond the boundary of the certified municipal setting designation, provided such action is necessary to ensure:
(1) the protection of humans from exposures to environmental impacts to groundwater; or
(2) the protection of ecological resources.
(g) This subchapter relates to the scope of the response action that can be required by the executive director in municipal settings designated under this subchapter. Nothing in this subchapter shall be construed to alter or affect the private rights of action of any person under any statute or common law for personal injury or property damage caused by the release of contaminants. Nothing in this subchapter is meant to alter or supersede any requirement of a federally authorized environmental program administered by the State of Texas.