ATCP 93.515(5)(5) Automatic tank gauging. Automatic tank gauging shall meet all of the following requirements: ATCP 93.515(5)(a)1.1. No more than 30 days may elapse between monthly monitoring tests using an automatic tank gauge. ATCP 93.515(5)(a)3.3. An automatic tank gauge shall be placed in the center of the tank and no closer than 12 inches from the fill pipe and the submersible pump. ATCP 93.515(5)(b)(b) Automatic tank gauges shall be provided with a printer that provides at least all of the following information: ATCP 93.515(5)(b)3.3. The measured leak rate in gallons per hour and whether this leak rate indicates a pass or a fail. ATCP 93.515(5)(b)4.4. The specific identification of the tank, associated piping, or sumps used for interstitial monitoring that are being tested. ATCP 93.515(5)(c)(c) Automatic tank gauges shall be programmed to provide an audible and visual alarm in the event of a tank or line test failure, a periodic monthly tank or line test not performed within a 30-day interval, or a tank or line interstitial sensor actuation. Manual operator action shall be needed to silence the alarm. ATCP 93.515(6)(a)2.2. Be capable of detecting a leak rate of 0.2 gallon per hour or a release of 150 gallons within 30 days; and ATCP 93.515(6)(a)3.3. Use a threshold that does not exceed one-half the minimum detectable leak rate. ATCP 93.515(6)(b)(b) Tank systems or portions of tank systems using statistical inventory reconciliation as the primary method of leak detection shall be monitored and evaluated for leaks at least every 30 days with a conclusive result of pass or fail within the 30-day monitoring period. ATCP 93.515(6)(c)(c) The daily tank system product inventory records shall be kept current and shall be maintained on site. ATCP 93.515(6)(d)(d) Tank product level measurements shall be recorded using an electronic inventory probe or an automatic tank gauge. ATCP 93.515(6)(e)(e) The operator shall have an effective process to submit their data to the vendor according to the vendor requirements for producing an evaluation report within the 30-day monitoring period. ATCP 93.515(6)(f)(f) The statistical inventory reconciliation vendor shall analyze the data and supply an evaluation report to the operator within the 30-day monitoring period. ATCP 93.515(6)(g)(g) If the result of the 30-day monitoring period is inconclusive or missing, another method of leak detection shall be used to determine a conclusive pass or fail for that monitoring period. ATCP 93.515(6)(h)(h) If during the initial 30-day monitoring period, a conclusive result has not been obtained, another method of leak detection shall be used to determine a conclusive pass or fail for that monitoring period. ATCP 93.515(6)(i)(i) Operators using statistical inventory reconciliation shall review the vendor summary report within 24 hours of receipt. If the summary report indicates a failure, the operator shall take immediate action in accordance with the requirements in ss. ATCP 93.575 to 93.585 for assessing and responding to a leak or release. ATCP 93.515(6)(j)(j) Statistical inventory reconciliation may not be used as a method of precision tightness testing. ATCP 93.515(6)(L)(L) Before changing from another method of leak detection to statistical inventory reconciliation, the operator shall provide the department with proof that precision testing was performed in accordance with sub. (4) within the previous 12 months, showing the tank system to be liquid-tight. ATCP 93.515(7)(7) Interstitial monitoring. Interstitial monitoring between an underground tank system and a secondary barrier immediately around it may be used only if the system is installed and maintained to detect a leak from any portion of the tank that could contain product, and the system meets one of the following requirements: ATCP 93.515(7)(a)(a) System testing. Post-installation testing shall be performed on the interstitial monitoring system to verify that the system operates in accordance with the manufacturer’s specifications.