Section 173-360-370. Release investigation and confirmation steps.

Unless corrective action is initiated in accordance with WAC 173-360-399, owners and operators shall immediately investigate and confirm all suspected releases of regulated substances requiring reporting under WAC 173-360-360 within seven days of discovery, or another reasonable time period specified by the department or delegated agency, using either the following steps or another procedure approved by the department or delegated agency:

(1) System test. Owners and operators shall have tests conducted (according to the requirements for tightness testing in WAC 173-360-345 (6)(d) and 173-360-350 (3)(b)) that determine whether a leak exists in any portions of the UST system that routinely contains a regulated substance, including the tank and the attached delivery piping, and in any connected tanks and piping that may or may not be in use. All such portions shall be tested either separately or together or in combinations thereof.

(a) Owners and operators shall have their system repaired, replaced, upgraded or closed by a certified UST supervisor and shall begin corrective action in accordance with WAC 173-360-399 if the test results for the system, tank, or delivery piping indicate that a leak exists.

(b) Further investigation is not required if the test results for the system, tank, and delivery piping do not indicate that a leak exists and if environmental contamination is not the basis for suspecting a release.

(c) Owners and operators shall conduct a site check in accordance with subsection (2) of this section if the test results for the system, tank, and delivery piping do not indicate that a leak exists but environmental contamination is the basis for suspecting a release.

(2) Site check. Owners and operators shall have a certified UST supervisor, as specified in WAC 173-360-610, sample for the presence of a release. Such samples shall be taken, analyzed, and results reported to the department or delegated agency in accordance with the department's guidance document for site checks and site assessments, or as otherwise directed by the department or delegated agency, where contamination is most likely to be present at the UST site.

(a) If the site check results indicate that a release has occurred, owners and operators shall report to the department or delegated agency in accordance with WAC 173-360-372 and begin corrective action in accordance with WAC 173-360-399.

(b) If the site check results indicate that a release has occurred, further investigation is not required under this chapter, but the release must be characterized and remediated in accordance with chapter 173-340 WAC.

(3) Certified UST supervisors who perform any of the tank services described in this section, shall certify that such services comply with the requirements of this section by signing the appropriate checklist(s) provided by the department.

[Statutory Authority: Chapter 90.76 RCW. WSR 95-04-102, § 173-360-370, filed 2/1/95, effective 3/4/95; WSR 91-22-020 (Order 91-26), § 173-360-370, filed 10/29/91, effective 11/29/91; WSR 90-24-017, § 173-360-370, filed 11/28/90, effective 12/29/90.]

Chapter 90.76 RCW. WSR 95-04-102, § 173-360-370, filed 2/1/95, effective 3/4/95; WSR 91-22-020 (Order 91-26), § 173-360-370, filed 10/29/91, effective 11/29/91; WSR 90-24-017, § 173-360-370, filed 11/28/90, effective 12/29/90.

Rules

173-360-399,173-360-360,173-360-345,173-360-350,173-360-399,173-360-610,173-360-372,173-360-399,173-340,