Sec. 26.10.02.03-2. New Gasoline UST System

The owner of a new gasoline UST system in a high-risk groundwater use area shall:

A. Install all piping, including Stage II vapor recovery piping, in accordance with COMAR 26.10.03.02;

B. Install and utilize, on the piping, an interstitial release detector system approved by the National Work Group on Leak Detection Evaluations;

C. For USTs with a capacity of greater than 2,000 gallons or for multiple tanks in a shared tank excavation:

(1) Install four monitoring pipes in accordance with the specifications in COMAR 26.10.03.04B, so that one monitoring pipe is located in each corner of the tank excavation area; and

(2) In conjunction with the monitoring pipes, install a piping system that is designed to allow for active ventilation of the tank excavation area;

D. Before placing the UST system in service, test the system for leaks using a helium pressure test, or other test approved by the Department, in accordance with procedures prescribed by the Department;

E. Implement one of the following:

(1) Install a minimum of three groundwater monitoring wells outside the UST excavation area in locations that will determine groundwater flow and detect a release from the UST system in accordance with COMAR 26.04.04 and Department specifications;

(2) Install a pressure control system that:

(a) Is approved by the Department;

(b) Is continuously operated;

(c) Continuously monitors tank pressures;

(d) Maintains tank pressure at an average negative pressure; and

(e) Prevents the release of gasoline vapors to the environment.

(3) Install a soil vapor extraction system in conjunction with the monitoring pipes that will allow for continuous active ventilation of the tank excavation area; or

(4) Obtain Department approval for an alternative method that will prevent and detect the release of gasoline liquid and vapors from the UST system;

F. In addition to requirements for release detection in COMAR 26.10.05:

(1) Test all spill catchment basins and containment sumps in accordance with COMAR 26.10.03.03;

(2) Within 30 days of the new gasoline UST system installation:

(a) Sample each site supply well and monitoring well using a method approved by the Department; and

(b) Test each sample obtained in §F(2)(a) of this regulation in accordance with Regulation .03-3 of this chapter;

(3) Annually thereafter sample and test as required in §F(2)(a)-(b) of this regulation; and

(4) Test the UST system after any repairs are completed in accordance with Regulation .03-4A(2) of this chapter.