|
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
NON-VOLUMETRIC
TANK TIGHTNESS TEST METHOD (TRACER)
|
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 tank system
should not be declared tight when tracer chemical greater
than the background level is detected outside of the tank
system.
|
|
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.
|
|
Tank Capacity
|
Not limited
by capacity.
|
|
Waiting Time
|
Ranges from
7 to 30 days after tracer is added to tank without the
support of on site leak simulation.
The waiting period may be adjusted outside this range
when supported by on site leak simulation performed as
described below.
|
|
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.
|
|
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.
All tank surfaces must be 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.
|
|
Groundwater
|
Depth to groundwater
in tank excavation backfill must be determined.
For test method to detect a release of tracer chemical
below groundwater, the hydrostatic pressure of product
in the tank must exceed the hydrostatic pressure of groundwater
during test.
To accomplish this, product level must be maintained at
least 6 inches above groundwater for a minimum 17 hours
during the first three days following addition of tracer
to the tank.
At the discretion of the regulatory agency, water ingress
measuring devices may be used to supplement test method
in high groundwater conditions.
|
|
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 above bottom of tank may limit effectiveness
of test method (e.g. when applied to tanks 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:
10/04/90
|
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.
|
|
