UST Programs - LG 113

Triangle Environmental, Inc.

TEI System 4000, Version 1.0

VOLUMETRIC TANK TIGHTNESS TEST METHOD (UNDERFILL)

Certification	Leak rate of 0.1 gph with PD = 99% and PFA = 4.8%.
Leak Threshold	0.05 gph. A tank system should not be declared tight if the test result indicates a loss or gain that equals or exceeds this threshold.
Applicability	Gasoline, diesel, fuel oil #4. Other liquids with known coefficients of expansion and density may be tested after consultation with the manufacturer.
Tank Capacity	Maximum of 15,000 gallons. Tank must be between 50 and 100% full.
Waiting Time	Minimum of 6 hours between delivery and testing. There must be no dispensing or delivery during waiting time.
Test Period	Minimum is determined by system's computer. Average was 4 hours during the evaluation. Leak rate is calculated from last 2 hours of test period data. Test data are acquired and recorded by system's computer. There must be no dispensing or delivery during test.
Temperature	Average for product is determined by a minimum of 3 thermistors.
Groundwater	Depth to groundwater in tank excavation backfill must be determined. If groundwater is above bottom of tank, product level must be adjusted to provide a minimum net pressure of 1 psi at bottom of tank during test.
Calibration	Thermistors must be calibrated before each test in accordance with manufacturer's instructions.
Comments	Not evaluated using manifolded tank systems. Tests only portion of tank containing product. As product level is lowered, leak rate in a leaking tank decreases (due to lower head pressure). Consistent testing at low levels could allow a leak to remain undetected. EPA leak detection regulations require testing of the portion of the tank system which routinely contains product. May also be used as an overfill test method.

Triangle Environmental, Inc.
3726 Park Place
Montrose, CA 91020
(818) 301-7777

Evaluator: United States Testing Company
Tel: (213) 723-7181
Date of Evaluation: 04/02/91

Appearance on this list is not to be construed as an endorsement by any regulatory agency nor is it any guarantee of the performance of the method or equipment.
Equipment should be installed and operated in accordance with all applicable laws and regulations.
For full details, please refer to our expanded "DISCLAIMER" page.