|
Issue Date: November 22, 1995
Revision Date: October 5, 2010
Containment
Solutions, Inc.
(originally listed as Fluid Containment and O/C Tanks)
Hydrostatic Precision Tank
Test for DWT-Type II Tanks
INTERSTIITIAL TANK TIGHTNESS
TEST METHOD
| Certification |
Leak rate of 0.1
gph with PD = 99.9% and PFA = 1.2% without dispensing.
Leak rate of 0.1 gph with PD = 95% and PFA = 5.0% with dispensing. |
| Leak
Threshold |
0.05 gph without
dispensing and 0.07 gph with dispensing.
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, motor oil, biodiesel blends B6-B20 meeting
ASTM D7467, biodiesel B100 meeting ASTM D6751.
|
| Tank
Capacity |
Maximum of 30,000
gallons.
Tank must be between 0 and 100% full. Maximum tank diameter is 10 feet. |
| Waiting
Time |
Minimum of 24
hours between delivery and testing.
Minimum of 3 hours between "topping off" the annular space with
liquid and testing.
There must be no delivery during waiting time. |
| Test
Period |
Minimum of 4
hours.
A leak is not declared unless the threshold is exceeded in two tests,
separated by at least 8 hours which are performed without dispensing and
with minimal changes in groundwater elevation above bottom of tank as
described below. |
| Other
Limitations |
Volume of trapped
vapor must not exceed 20 gallons.
Change in barometric pressure must be less than 0.04 psia over the 4-hour
test period.
Annular space must be at least 100% full with either water or
antifreeze.
If groundwater is above bottom of tank, and no product is being dispensed
during test, total change in groundwater elevation during test must be
less than 1.5 inches per hour.
If groundwater is below bottom of tank or not changing during test, total
change in product level during test must be less than 0.75 inch per hour. |
|
Containment Solutions, Inc.
|
Evaluator: Vista
Research
|
|
5150 Jefferson Chemical
|
Tel: (415) 966-1171
|
|
Conroe, TX 77301-6834
|
Date of Evaluation: 05/15/91
|
|
Tel: (800) 628-2657
|
|
|
E-Mail: dheiman@csiproducts.com |
|
|
URL: www.containmentsolutions.com |
|
|
