SECTION 350.35. Substantial Change in Circumstances

(a) Upon receipt of approval by the executive director of the RACR, performance of applicable post-response action care, maintenance of any applicable financial assurance, and termination of any applicable post-response action care period by the executive director, the person will have completed the obligations of this chapter unless a substantial change in circumstances results in an unacceptable risk to human health or the environment.

(b) No person shall cause, suffer, allow, or permit a threat to human health or the environment by changing a land use specified in an approved RACR from commercial/industrial to residential or by removing, altering or failing to maintain a physical or institutional control that applies to an affected property that underwent an approved response action.

(c) If a person plans to change the land use from commercial/industrial to residential, or to eliminate or modify the use of a physical control or institutional control, then that person shall take any actions necessary to make the property protective for such changed conditions. The person making the change shall notify the executive director in writing at least 60 days prior to changing the land use or the use of the approved physical or institutional controls. The person may self-implement actions to satisfy the requirements of paragraph (1) or (2) of this subsection but must obtain prior approval of the executive director to undertake actions for paragraph (3) of this subsection. The person making the change shall then provide a reevaluation of the property at least 30 days prior to the date of the planned change such that the person is able to demonstrate:

(1) that levels of COCs have degraded to concentration levels below the applicable critical PCLs for the planned land use or property condition change;

(2) that the COC removal or decontamination will meet the applicable critical PCLs for the planned land use or property condition change; or

(3) that the application of a proposed physical and/or institutional control will ensure adequate protection of human health and the environment. Any proposed institutional control shall conform with all requirements of §350.111 of this title (relating to Use of Institutional Controls).

(d) A substantial change in circumstances shall include, but is not limited to, the situations described in paragraphs (1)-(5) of this subsection. In response to these substantial changes in circumstances, the person shall use the rule in effect at the time of the substantial change to protect human health or the environment. This subsection will only apply to affected properties regulated under §350.2(g) of this title (relating to Applicability) which have completed response actions under this chapter.

(1) An institutional or physical control fails to prevent exposure at the approved performance level.

(2) An actual exposure condition is determined to be occurring at levels not protective of human health or the environment (e.g, unprotective ecological exposure is occurring).

(3) New information indicates that the presence of COCs at the affected property was not sufficiently characterized such that an unacceptable threat to human health or the environment continues to exist.

(4) The exposure area upon which representative concentrations are based in accordance with §350.51 of this title (relating to Affected Property Assessment) changes, and as a result of the changed exposure area, there is an unacceptable threat to human health or the environment.

(5) A health and safety plan to ensure compliance with occupational inhalation criteria as RBELs as provided for in §350.74(b)(1) of this title (relating to Development of Risk-Based Exposure Limits) will no longer be maintained.

(e) For purposes of this section, changes made to this chapter in response to periodic reviews of the general procedures specified to generate PCLs, or in response to revisions to reflect new toxicity data, do not constitute a substantial change in circumstances, unless these changes are of such magnitude to present an unacceptable threat to human health or the environment when evaluated for future exposure conditions based on property-specific considerations. This subsection will only apply to affected properties regulated under §350.2(g) of this title (relating to Applicability) which have completed response actions under this chapter.

(f) If the person determines that the conditions specified in subsection (c)(1) or (2) of this section are met such that a deed notice, VCP certificate of completion, or restrictive covenant is no longer needed to protect human health and the environment, then the person may request that the executive director approve a superceding deed notice in accordance with §350.111(b)(4) of this title (relating to Use of Institutional Controls) or a restrictive covenant release in accordance with §350.111(b)(7) of this title (relating to Use of Institutional Controls) if a deed notice or restrictive covenant was the form of institutional control. The person shall provide the necessary information to document that the conditions of subsection (c)(1) or (2) of this section are met.

Source Note: The provisions of this §350.35 adopted to be effective September 23, 1999, 24 TexReg 7436