PURPOSE: This rule describes the procedures for soil and groundwater investigations.

Editor’s Note: The secretary of state has determined that the publication of this rule in its entirety would be unduly cumbersome or expensive. The entire text of the material referenced has been filed with the secretary of state. This material may be found at the Office of the Secretary of State or at the headquarters of the agency and is available to any interested person at a cost established by state law.

1. (1) Owners and operators must conduct investigations of the release, the release site and the surrounding area to determine the full extent and location of soils contaminated by the release and the presence and concentrations of dissolved product contamination in the groundwater if any of the following conditions exist:

   1. (A) There is evidence that groundwater wells have been affected by the release (for example, as found during release confirmation or previous corrective action measures);
   2. (B) Free product is found to need recovery in compliance with 10 CSR 20-10.064;
   3. (C) There is evidence that contaminated soils may be in contact with groundwater as found during the initial response measures or investigations required under 10 CSR 20- 10.060—10 CSR 20-10.064; or
   4. (D) The department requests an investigation based on the potential effects of contaminated soil or groundwater on nearby surface and ground water resources.
2. (2) Owners and operators must submit the information collected under section (1) of this rule as soon as practicable or in accordance with a schedule established by the department.
3. (3) Owners and operators shall follow a written procedure. To comply with this rule, the department’s Site Characterization Guidance Document may be used as a written procedure. Other written procedures may be used with prior written approval of the department. AUTHORITY: sections 319.109, RSMo Supp. 1989 and 644.026, RSMo Supp. 1993.* Original rule filed April 2, 1990, effective Sept. 28, 1990. Amended: Filed Aug. 3, 1993, effective April 9, 1994. *Original authority: 319.107, RSMo 1989 and 644.026, RSMo 1972, amended 1973, 1987, 1993.