N.H. Admin. Code § Env-Or 408.08

Current through Register No. 50, December 12, 2024

Section Env-Or 408.08 - Permanent Closure: Site Assessment

The site assessment required by Env-Or 408.07(g) shall be conducted in accordance with Env-Or 600 and the following:

(a) Test pits shall be excavated in the immediate vicinity of the tank and piping to a depth as close to the bottom of the tank and piping as possible;

(b) Representative samples of soil and, when encountered, groundwater, shall be obtained from:

(1) The test pits;

(2) The excavation zone resulting from the removal of the UST and the piping, for USTs and piping that are removed;

(3) Representative locations adjacent to and beneath the UST, including access points through the tank wall, for any UST that will be closed in place; and

(4) Locations adjacent to the system's piping that could not be removed, unless the piping passes a tightness test pursuant to Env-Or 408.07(d)(2), including;

a. At multiple locations along the piping run, separated by no more than 10 feet; and

b. At piping connections, bends, and joints.

(c) If soil that normally would remain in or be returned to the excavation is removed from the site by the owner as a presumptive remedy during tank closure activities, additional samples shall be taken from beneath the excavated area;

(d) The excavation zone where the UST system or UST system component was located shall be screened in the field for the presence of contamination by visual and olfactory observation and headspace analysis performed with equipment such as a portable organic vapor meter (OVM) or portable gas chromatograph (GC);

(e) Soil samples shall be collected for laboratory analysis as follows:

(1) If field screening does not indicate a release, a minimum of one composite soil sample comprised of at least 5 discrete grab samples shall be collected from representative locations immediately beneath and adjacent to each tank and piping system; and

(2) If field screening or physical observations, or both, indicate a potential release, a minimum of 2 discrete soil samples shall be collected from representative locations immediately beneath and adjacent to each closed tank or piping system with the highest observed contamination;

(f) If field screening or physical observations, or both, indicate a potential release and the facility is served by a water supply well, a water supply well sample shall be collected prior to any treatment system for laboratory analysis.

(g) Each sample taken shall be analyzed for constituents of the regulated substance stored in the system by a laboratory certified under Env-C 300 for those constituents; and

(h) If soil or groundwater contamination from a regulated substance is detected by observation or analysis during closure of a UST system, any owner or operator or other individual shall immediately notify the department as required by RSA 146-A:5.

N.H. Admin. Code § Env-Or 408.08

(See Revision Note at chapter heading for Env-Or 400) #10393, eff 9-1-13

Amended by Volume XXXVIII Number 45, Filed November 8, 2018, Proposed by #12643, Effective 10/10/2018, Expires 10/10/2028.