Issue Date: March 10, 2000
Revision Date: December 4, 2002
(originally listed as Tracer Research Corp.)
2000 Automated Line Tightness Test
Line Leak Detection Method for Airport Hydrant and Field Constructed Systems
||Leak rate of 0.1
gph with PD = 100% and PFA = 0%.
The USEPA has not set a minimum detectable leak rate for large diameter
pipeline systems (airport hydrant systems) at the time of this evaluation.
||A pipeline system
should not be declared tight when tracer chemical or hydrocarbon greater
than the background level is detected outside of the pipeline system.
aviation fuel, fuel oil #4, waste oil.
||Not limited by
||Ranges from 1
week to 4 weeks (normally 2 weeks) after tracer is added to tank.
For very large pipeline systems, several days or weeks may be required to
circulate tracer-labeled product through all parts of the pipeline.
Waiting time begins after tracer has reached all portions of the pipeline
||Tracer is added
to tank manually or automatically using a metered injection pump at tank
fill or tank discharge pipeline.
Tracer-labeled product must be circulated through pipeline before test
Pressurized pipeline must be brought up to operating pressure or operated
on a daily basis.
Manual dosage of tracer is based on tank size, product volume in tank, and
frequency and volume of tank refills according to manufacturer's
Automated pipeline injection uses metered injection pumps to automatically
inject tracer every time product flows through pipeline.
Dosage is based on pipeline size and flow rate.
must readily allow tracer movement through the tank excavation backfill
(greater than 1 Darcy).
influence of each tracer sampling probe is maximum 10 feet.
Pipeline must be accurately located to ensure that all pipeline surfaces
are within the zone of influence of a sampling probe.
Probes must be installed per manufacturer's guidelines.
||The presence of a
layer of water saturated soil, that is also frozen, above the location where
a leak may exist, may inhibit the effectiveness of the method by impeding
the transport of the tracer labeled product into the unsaturated zone.
Groundwater surrounding pipeline may limit effectiveness of test method
(e.g. when applied to pipelines containing water-miscible products or
products whose specific gravity is greater than 1).
Test method may not be effective in some tank excavation backfill (such as
clay) because it may plug holes in pipeline and retard tracer movement
through the soil.
Third party evaluation of the ALD 2000 System tested the device's ability
to collect a sample, transport sample through 2700 feet of 3/32 inch
tubing, and analyze sample.
Sample collection, analysis, data storage, and alarm activation is
controlled by system's computer.
Prior evaluations tested PD, PFA, leak threshold, dose, tracer movement
through soil, and waiting times.
Praxair Services, Inc.
Ken Wilcox Associates
3755 N. Business Center Dr.
Dates of Evaluation:
Evaluator: Control Strategies Engineering (out of business)
Tel: Contact Praxair Services, Inc.
of Evaluation: 05/92