|
Issue Date: April 17, 2002
Revision Date: January 12, 2011
USTest, Inc.
(previously listed as Sound Products Manufacturing, Inc.)
UST 2001/P
(Ultrasonic Probe)
VOLUMETRIC
TANK TIGHTNESS TEST METHOD (UNDERFILL)
| Certification |
Leak rate of 0.1 gph with PD =
97.0% and PFA = 0.6% |
| 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, aviation fuel, fuel oil
#4. |
| Tank Capacity |
Maximum of 20,000 gallons.
Minimum product level required is 15 inches (1 inch above lowest calibration
rod). |
| Waiting Time |
Minimum of 4 hours between delivery and
testing.
There must be no dispensing or delivery during waiting time. |
| Test Period |
Minimum of 1 hour.
There must
be no dispensing or delivery during test. |
| Temperature |
Average for product is determined by an
ultrasonic probe containing 5 temperature targets.
Targets located above the
product surface are not used in data analysis.
If a test is to be conducted following a product delivery, the temperature
difference between the product in the tank and the product delivered should
not exceed 7.7
degrees F. |
| 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 the tank during test. |
| Calibration |
Probe must be checked regularly and, if
necessary, calibrated in accordance with manufacturer’s instructions. |
| Comments |
System consists of an ultrasonic probe which
interfaces with a micro processing unit.
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.
|
|
Southwest Environmental
Services, Inc. |
Ken Wilcox Associates |
|
102 Abigayle Row |
Tel: (816) 443-2494 |
|
Scott, LA 70508 |
Date of Evaluation: 07/11/01 |
|
Tel: (337) 235-1184 |
|
|
