310 CMR, § 80.26 - Requirements for Leak Detection Systems

(1) The Owner or Operator shall equip UST systems with a leak detection system for tanks and piping in accordance with manufacturer's specifications and 310 CMR 80.19.

(2) The Owner or Operator shall operate and maintain leak detection systems at all times and in accordance with manufacturer's specifications and 310 CMR 80.26, as applicable. As applicable, the Owner or Operator shall inspect and test leak detection systems annually, as follows:

(a) For in-tank monitors and other controllers:

1. Test alarms;

2. Verify system configuration; and

3. Test battery backup.

(b) For probes and sensors:

1. Inspect for residual buildup and remove buildup as necessary;

2. Ensure floats move freely;

3. Ensure shaft is not damaged;

4. Ensure cables are free of kinks or breaks; and

5. Test alarm operability and communication with controller.

(c) For automatic line leak detector: test operation to meet criteria in 310 CMR 80.19(4)(a)2., 310 CMR 80.80.19(4)(b)2., and 310 CMR 80.19(4)(c)2., by simulating a leak.

(d) For vacuum pumps and pressure gauges: ensure proper communication with sensors and controller.

(e) Repair and replace leak detection systems and components, as necessary.

(f) Keep records of inspection results, repairs and replacements in accordance with 310 CMR 80.36.

(3) Requirements for UST systems that continuously monitor interstitial space in a double-walled tank and/or double-walled piping as its primary leak detection system are as follows:

(a) Sensors shall continuously monitor interstitial space and be maintained in good working order and shall be operated to perform their original design function in accordance with the manufacturer's specifications.

(b) Interstitial space shall be free of solid material, water and regulated substance. Water in 310 CMR 80.26(3)(b) does not include brine or condensation that occurs in a properly operating UST system.

(c) If a release or leakage is indicated by alarm or otherwise, the Owner or Operator shall immediately commence an investigation to determine whether there may be a release or leakage. The Owner or Operator shall conclude the investigation within 72 hours of the indication of release or leakage.

(d) If the Owner or Operator is unable to determine that there is not a release or leakage within 72 hours of the indication of release or leakage, he or she shall conduct a tightness test of the suspected tank or piping in accordance with 310 CMR 80.32 within 72 hours after the conclusion of the investigation.

1. If the tank or piping fails a tightness test pursuant to 310 CMR 80.32, the Owner or Operator shall comply the requirements at with 310 CMR 80.32(3), as applicable.

2. If the tank and the piping pass a tightness test pursuant to 310 CMR 80.32, the tank and the piping are considered tight, and the requirements for tightness testing are satisfied.

3. If the investigation or the tightness test indicates leakage, the Owner or Operator shall comply with 310 CMR 80.39.

(e) The Owner or Operator shall keep records of all investigations and monthly liquid status reports in hard copy if electronically (but not electronically in the leak detection system), in accordance with 310 CMR 80.36.

(4) Requirements for those UST systems that use an in-tank monitoring system as its primary leak detection system are as follows:

(a) At least once each calendar month, the Owner or Operator shall conduct a test using the in-tank monitor over a continuous period of time as prescribed by the manufacturer's specifications, during which no regulated substance shall be delivered to or taken from the tank, in order to determine whether there is a release or leakage of regulated substance. If the manufacturer's specifications do not prescribe a continuous period of time, the continuous period of time shall be six hours. A loss of 0.20 gallons per hour or more over the testing period with the probability of detection of 0.95 and a probability of false alarm of 0.05 shall indicate a release or leakage.

(b) If at the end of the calendar month, the tank has not passed a test in accordance with 310 CMR 80.26(4)(a), the Owner or Operator shall conduct a tightness test of the suspected tank and piping in accordance with 310 CMR 80.32 within 72 hours of the end of the calendar month.

1. If the tank or piping fails a tightness test pursuant to 310 CMR 80.32, the Owner or Operator shall comply with 310 CMR 80.32(3), as applicable.

2. If the tank and the piping pass a tightness test pursuant to 310 CMR 80.32, the tank and the piping are considered tight, and the requirements for tightness testing are satisfied.

(c) The Owner or Operator shall keep records of all investigations and passing monthly tests in hard copy or electronically (but not electronically in the leak detection system), in accordance with 310 CMR 80.36.

(5) Requirements for those UST systems that use a continuous in-tank detection system as its primary leak detection system are as follows:

(a) Throughout each calendar month, the Owner or Operator shall ensure that the continuous in-tank monitoring system is operating in accordance with the manufacturer's specifications.

(b) A loss of 0.20 gallons per hour with the probability of detection of 0.95 and a probability of false alarm of 0.05 shall indicate a release or leakage.

(c) If at the end of the calendar month, the continuous in-tank monitoring system indicates a release or leakage in accordance with 310 CMR 80.26(5)(b), the Owner or Operator shall conduct a tightness test of the suspected tank or piping pursuant to 310 CMR 80.32 within 72 hours of the end of the calendar month.

1. If the tank or piping fails a tightness test pursuant to 310 CMR 80.32, the Owner or Operator shall comply with 310 CMR 80.32(3), as applicable.

2. If the tank and the piping pass a tightness test pursuant to 310 CMR 80.32, the tank and the piping are considered tight, and the requirements for tightness testing are satisfied.

(d) If the continuous in-tank monitoring system does not produce sufficient data to obtain a conclusive result, the Owner or Operator shall within 24 hours of the end of the calendar month take the tank out of service to allow the continuous in-tank monitoring system the minimum sufficient quality test time in accordance with the manufacturer's specification.

(e) If after complying with 310 CMR 80.26(5)(d), the Owner or Operator is still unable to obtain a passing result, the Owner or Operator shall comply with 310 CMR 80.26(5)(c) within 96 hours of the end of the calendar month.

(f) The Owner or Operator shall keep records of all investigations and passing monthly tests in hard copy or electronically (but not electronically in the leak detection system), in accordance with 310 CMR 80.36.

(6) Requirements for an in-tank monitoring system that uses statistical inventory reconciliation (SIR) as its primary leak detection system are as follows:

(a) The Owner or Operator shall have an inventory analyses conducted by a qualified SIR vendor who analyzes inventory, delivery, and dispensing data collected over a calendar month to determine whether or not the UST system has a release or leakage.

(b) The Owner or Operator shall have equipment and procedures in place to assure that the data provided to the SIR vendor is accurate.

(c) If the SIR analysis is conclusive and identifies a release or leakage, the Owner or Operator shall conduct a tightness test of the suspected tank or piping pursuant to 310 CMR 80.32 within 72 hours of obtaining knowledge of the suspected release or leakage.

1. If the tank or piping fails a tightness test pursuant to 310 CMR 80.32, the Owner or Operator shall comply with 310 CMR 80.32(3), as applicable.

2. If the tank and the piping pass a tightness test pursuant to 310 CMR 80.32, the tank and the piping are considered tight, and the requirements for tightness testing are satisfied.

(d) If the SIR analysis is inconclusive, the Owner or Operator shall immediately, upon obtaining knowledge of the inconclusive result, commence an investigation to determine whether there is a release or leakage. the Owner or Operator shall conclude the investigation within 72 hours upon obtaining knowledge of the inconclusive result. If the Owner or Operator is unable to determine that there is not a release or leakage within 72 hours upon obtaining knowledge of the inconclusive result, he or she shall conduct a tightness test pursuant to 310 CMR 80.32 within 72 hours of the conclusion of the investigation.

1. If the tank or piping fails a tightness test pursuant to 310 CMR 80.32, the Owner or Operator shall comply with 310 CMR 80.32(3), as applicable.

2. If the tank and the piping pass a tightness test pursuant to 310 CMR 80.32, the tank and the piping are considered tight, and the requirements for tightness testing are satisfied.

(e) If the SIR analysis is conclusive and does not identify a release or leakage of regulated substance, the tank is considered tight.

(f) The Owner or Operator shall keep records of all investigations and SIR analyses in accordance with 310 CMR 80.36.

(7) Until October 13, 2022, UST systems having a capacity of 1000 gallons or less, installed before January 2, 2015, that supply regulated substance to emergency engines may conduct weekly tank gauging as its primary leak detection system are as follows:

(a) Manual tank gauging shall be conducted every seven days.

(b) Manual tank gauging shall be conducted as follows:

1. Tank liquid level measurements shall be taken and recorded, including date and time of measurements, at the beginning and ending of a period of at least 36 hours during which no liquid is added to or removed from the tank;

2. Level measurements shall be based on an average of two consecutive stick readings at the beginning and the ending of the period;

3. The equipment used shall be capable of measuring the level of regulated substance over the full range of the tank's height to the nearest 1/8 of an inch;

4. A release or leakage shall be suspected if the variation between beginning and ending measurements exceeds the weekly or monthly standard in 310 CMR 80.26(7)(b)4.: Table D:

Table D

Nominal Tank Capacity	Weekly Standard (One Test)	Monthly Standard (Average of Four Tests)
500 gallons or less	10 gallons	5 gallons
501 through 1,000 gallons	13 gallons	7 gallons

(c) In the event of a suspected release or leakage, the Owner or Operator shall comply with 310 CMR 80.31(1)(e),(f) and (g).

(d) The Owner or Operator shall keep records of the results of weekly tank gauging accordance with 310 CMR 80.36.

(8) Until October 13, 2022, UST systems having a capacity of more than 1000 gallons, installed before January 2, 2015 that supply regulated substance to emergency engines may conduct monthly tank gauging as its primary leak detection system are as follows: (These UST systems shall also conduct an annual tightness test in accordance with 310 CMR 80.32).

(a) Manual tank gauging shall be conducted every 30 days.

(b) Manual tank gauging shall be performed as follows:

1. Tank liquid level measurements shall be taken and recorded, including date and time of measurements, at the beginning and ending of a period of at least 36 hours during which no liquid is added to or removed from the tank;

2. Level measurements shall be based on an average of two consecutive stick readings at the beginning and the ending of the period;

3. The equipment used shall be capable of measuring the level of regulated substance over the full range of the tank's height to the nearest 1/8 of an inch;

4. A release or leakage shall be suspected if the variation between beginning and ending measurements exceeds the monthly standard in 310 CMR 80.26(8)(b)4.: Table E:

Table E

Nominal Tank Capacity	Monthly Standard
More than 1000 gallons	7 gallons plus 2 gallons for every additional 1000 gallons capacity

(c) In the event of a suspected release or leakage, the Owner or Operator shall comply with 310 CMR 80.31(1)(e), (f) and (g).

(d) The Owner or Operator shall keep records of the results of weekly tank gauging in accordance with 310 CMR 80.36.

(9) For piping installed before May 28, 1999, the Owner or Operator may conduct quarterly visual inspections of secondary containment ports and conduct an annual tightness test of the piping in accordance with 310 CMR 80.32. The Owner of Operator shall keep records of the visual inspections and the tightness tests in accordance with 310 CMR 80.36.

(10) Options for Owners and Operators of regulated substance piping installed before January 1,1989:

(a) Non-European suction piping, if it does not have secondary containment and continuous monitoring of interstitial space, shall comply with 310 CMR 80.49(4)(c)1.c. or e. The Owner and Operator shall maintain records of the tightness testing in accordance with 310 CMR 80.36.

(b) Single-walled pressurized piping systems and single-walled gravity piping systems shall comply with 310 CMR 80.19(4)(c)1.b., c. or d. The Owner and Operator shall maintain records of the tightness testing in accordance with 310 CMR 80.36.

(11) If the Owner or Operator cannot demonstrate that its European suction piping is sloped back to the tank and that its one check valve is located directly under the dispenser to the satisfaction of the Department including, but not limited to, an accurate drawing, as-built plans or installation records, it shall comply with the standards for non-European piping at 310 CMR 80.19(4)(a)1. 310 CMR 80.19(4)(b)1.(c)1., as applicable.

(12) The Owner or Operator shall test those components of the leak detection system that are repaired or replaced, prior to returning the leak detection system to service, to determine that they are operational. The Owner or Operator shall keep records of such tests in accordance with 310 CMR 80.36.

(13) All leak detection records required in 310 CMR 80.26(1) through (12) shall be kept in accordance with 310 CMR 80.36.

Notes

310 CMR, § 80.26

Adopted by Mass Register Issue S1277, eff. 1/2/2015. Amended by Mass Register Issue 1453, eff. 10/1/2021.