Issue
Date: January 11, 2001
Revision
Date: June 8, 2005
OPW
Fuel Management Systems
(originally listed as Emco Electronics, Tuthill
Transfer Systems)
EECO
System 1000, 1000EG, 1500, 2000, 3000 and Galaxy ATG Systems
(Q0400-4xx Magnetostrictive Probe)
CONTINUOUS
IN-TANK LEAK DETECTION METHOD (CONTINUOUS AUTOMATIC TANK GAUGING)
Certification
|
Leak
rate of 0.2 gph with PD = 99.1% and PFA = 0.9%.
|
Leak
Threshold
|
0.1
gph for single and manifolded tank systems.
A tank system should not be declared tight and a message
printed for the operator, if the test results indicate
a loss or gain that exceeds this threshold.
|
Applicability
|
Gasoline,
diesel, aviation fuel.
The system is designed primarily for use with petroleum
fuels.
Other liquids with known coefficients of expansion and
density may be tested after consultation with the manufacturer.
|
Tank
Capacity
|
Maximum
of 35,000 gallons for single tanks and for up to 2 tanks
manifolded together.
|
Throughput
|
Monthly
maximum of 130,000 gallons.
|
Waiting
Time
|
Minimum
of 6 hours stabilization time is allowed between delivery
and data collection.
|
Test
Period
|
Average
data collection time is 12 days.
During evaluation, data collection time ranged from 1
to 31 days.
Data sampling frequency is at least once per minute.
System collects data at naturally occurring product levels
without interfering with normal tank operation and discards
data from unstable periods when system performs test.
|
Temperature
|
Average
for product is determined by a minimum of 5 sensors.
|
Water
Sensor
|
Must
be used to detect water ingress.
Minimum detectable water level in the tank is 0.66 inch.
Minimum detectable change in water level is 0.039 inch.
|
Calibration
|
Temperature
sensors are factory calibrated.
Probe must be checked and, if necessary, calibrated in
accordance with manufacturer's instructions.
|
Comments
|
System reports a result
of "pass" or "fail."Evaluated using
both single and manifolded tank systems with probes
in each tank. Data can be collected when the product
level is between 9% and 94.9% of tank volume. System
distinguishes large leak rates (> 1gph) from dispensing
activities and reports those as "fail". For
valid monthly testing, a conclusive test report must
be produced for each tank every month. System warns
operator if there are no "passing" tests completed
during the month. For very active tanks, a tank shut
down may become necessary in order for the system to
collect enough quiet-time data for a test. The 6-hour
stabilization period after delivery may result in the
system not testing the top portion of a very active
tank. In this situation, a periodic test in the shut-down
mode with a high product level should be used to test
the entire portion of tank that routinely contains product.
Because the database for evaluation of the system did
not include sites with vapor recovery, certification
is limited to sites with no vapor recovery.Evaluated
using gasoline. |