Issue
Date: September 15, 2003
Revision Date: June 8, 2005
Warren Rogers Associates, Inc.
WRA PetroNetwork
S3 (Version D)
Continual Reconciliation System for CITLDS Using Multiple
ATG System
with Magnetostrictive Tank Probes for Tanks and Associated
Pipelines
CONTINUOUS
IN-TANK LEAK DETECTION METHOD (CONTINUAL RECONCILIATION)
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Certification
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Leak
rate of 0.2 gph for tanks and associated pipelines with
PD > 99% and PFA < 1%.
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Leak
Threshold
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0.1
gph for single and manifolded tank systems including associated
pipelines.
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.
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Applicability
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Gasoline,
diesel, aviation fuel, fuel oil #4.
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.
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Tank
Capacity
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Maximum
of 100,000 gallons for single tanks and for up to 5 tanks
manifolded together.
Tank must be between 9% and 94.4% full.
Contact manufacturer for tank system applications if total
tank capacity exceeds 100,000 gallons.
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Throughput
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Monthly
maximum of 2,718,013 gallons.
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Waiting
Time
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None
between delivery and data collection when difference between
product in tank and product delivered is 7.4 degrees F
or less.
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Test
Period
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Data
collection time ranges from 6 to 31 days.
Data sampling frequency is every 1 to 15 minutes.
System collects data at naturally occurring product levels
upon completion of a sales transaction or set of overlapping
sales transactions without interfering with normal tank
operation, and at time periods when the tank system is
dormant.
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Temperature
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Average
for product is determined by a minimum of 5 thermistors.
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Water
Sensor
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Must
be used to detect water ingress in accordance with the
certified performance of the Automatic Tank Gauge used.
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Calibration
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The
Automatic Tank Gauge used must have thermistors and probe
checked and, if necessary, calibrated in accordance with
manufacturer's instructions.
Meter calibration must be checked at outset of monitoring
and recalibrated when system detects significant departure
from original calibration.
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Comments
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Tests only the portion of
tank system containing product.
System reports a result of “pass” or “fail” and indicates
minimum detectable leak and leak threshold for tanks and
associated pipelines.
Evaluated for tanks and associated pipelines for both
single and manifolded tank systems with probes in each
tank.
For valid monthly testing, a conclusive report must be
generated for each tank system every month.
Constant and variable leaks were mathematically induced
into tight tank records and data collected at various
tank sites by previously evaluated Veeder-Root TLS-350
and OPW Fuel Management Systems EECO 1500 Automatic Tank
Gauges with magnetostrictive probes.
Automatic Tank Gauges used with this method must
be on the NWGLDE List, employ a magnetostrictive probe,
and be certified at a leak rate of 0.1 gph.
The database for evaluation of the system included tank
and pipeline leaks at sites with vapor recovery and blending
dispensers.
System is designed for use with pipelines equipped with
mechanical or electronic line leak detectors to detect
emergent catastrophic leaks in the pipelines.
Tank systems used in this evaluation contained gasoline
and diesel.
Custom tank charts are generated for each tank system.
Meter Drift analyses are performed during monitoring.
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