Issue
Date: November 22, 1995
Revision Date: October 2, 2003
Linde Services, Inc.
(Formally Praxair Services, Inc., originally listed as Tracer Research Corp.)
Tracer
Tight Line Test
LINE TIGHTNESS
TEST METHOD
Certification
|
Leak
rate of 0.1 gph with PD = 100% and PFA = 0%.
Leak rate of 0.005 gph with PD = 97% and PFA = 2.9%.
|
Leak
Threshold
|
A pipeline system should
not be declared tight when tracer chemical greater than
the background level is detected outside of the pipeline. |
Applicability
|
Gasoline,
diesel, aviation fuel, fuel oil #4, waste oil.
Other fluids which are compatible and soluble with an
acceptable tracer chemical may be tested after consultation
with the manufacturer.
|
Pipeline
Capacity
|
Not
limited by capacity.
|
Waiting
Time
|
Ranges
from 7 to 30 days after tracer is added to tank without
support of on-site simulation.
The waiting period may be adjusted below this range when
supported by on-site leak simulations performed as described
below.
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 being tested.
|
Leak
Simulations
|
The release of surrogate
tracer into the soil or backfill to evaluate the migration
of a tracer and the sensitivity of the test under on-site
sub-surface conditions. Sub-surface conditions throughout
the test area must be at least as favorable as those at
the leak simulations location in order to use the results.
This requirement may be satisfied by sampling the backfill
material, and/or making flow/vacuum measurements from
the sampling probes.
|
Tracer
Dosage
|
Dosage
of tracer is based on tank size, product volume in tank,
and frequency and volume of tank refills according to
manufacturer's recommendations.
Tracer-labeled product must be circulated through the
pipeline before test period begins.
Pressurized pipeline must be brought up to operating pressure
or operated on a daily basis.
|
Permeability
|
Soil
permeability must readily allow tracer movement through
the tank excavation backfill (greater than 1 Darcy).
|
Probe
|
Radius of 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.
Horizontal sampling probes may be installed in manufactured
backfill during the installation of a new UST system.
These probes must be installed per manufacturer's guidelines.
|
Comments
|
The
tester may determine that pre or post testing is needed
to establish the background level of tracer in the soil.
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).
|
Linde Services, Inc.
|
Evaluator: Ken Wilcox Associates
|
3755
N. Business Center Dr.
|
Tel: (816) 443-2494
|
Tucson,
AZ
85705
|
Date
of Evaluation:
10/04/91
|
Tel: (844) 445-4633
|
Evaluator: Control Strategies Engineering
- out of
business
|
E-mail: contactus@linde.com
|
Tel: Contact Linde Services, Inc.
|
URL: www.lindeservices.com
|
Date
of Evaluation: 05/92
|
Formerly Praxair Services, Incorporated. LG 113 name changed on October 1, 2020.
|
|