Leak Detection Equipment
Tank Tightness
Testing
Ed Kubinsky
Crompco
Tightness Testing
Why Is Tank Tightness Testing Necessary?
Satisfy Leak Detection Requirements
(along with Inventory Control)
Start-ups (contractor or owner request)
SIR failure or inconclusive results
Sudden release
Tank taking on water
Tightness Testing
Why Is Tank Tightness Testing
Necessary?
Accident
Request by a regulatory authority
ATG Failure
Property Transfer
Unexplained loss of product
Tightness Testing
Tank Tightness Testing Features:
Some tightness test methods are
“volumetric” methods in which the change
in product level is measured very precisely
in milliliters or thousandths of an inch.
Tightness Testing
Tank Tightness Testing Features:
With non-volumetric underfill vacuum tests,
the tester listens for sounds while the tank
is under vacuum to determine whether or
not the tank is leaking. A water sensor is
used to measure any water ingress during
the test.
Tightness Testing
Tank Tightness Testing Procedures:
Water table measurements and calculations
are made in order to determine the length
of the test and the amount of vacuum that
must be applied. The water sensor must be
used if the tank is submersed in water or if
the tank is DW with brine in the interstitial
space.
Tightness Testing
Tank Tightness Testing Procedures:
Once the required vacuum is achieved,
the technician listens for both ullage
leaks (hissing sounds) and leaks
below the product level (bubble
signatures). The technician also
monitors the water sensor for signs
of water ingress.
Tightness Testing
Tank Tightness Testing Features:
Some methods require all of the
measurements and calculations to be made
by the tester. Other methods are highly
automated. Once the tester sets up the
equipment, a computer controls the
measurement and analysis.
Tightness Testing
Tank Tightness Testing Features:
Tanks must be taken out of service for
tightness testing. The downtime depends on
the test method and issues encountered
during testing.
Tightness Testing
Tank Tightness Testing Features:
Some methods require that tanks be filled to
certain product levels. Check with your
testing company to find out the
requirements for their tank tightness
method.
Tightness Testing
Other considerations:
Used primarily on USTs no more than
30,000 gallons in capacity.
Tightness Testing
Other considerations:
Test method, procedure, equipment
and experienced personnel are all very
important factors in a successful tank
tightness test.
Therefore:
Tightness Testing
Make sure that your tester has been
certified by the equipment
manufacturer. Make sure that
equipment being used by the tester
has been certified and calibrated as
well.
Tank Tightness Testing
Using the EZY-3 Locator
Plus (Estabrook’s Inc.)
Individual Certification Required

Technicians must attend manufacturer training on the
equipment and then renew their certification every 2 years.
Annual Equipment
Calibration/Certification Required

Each piece of equipment
used must be sent back to
the manufacturer annually
for calibration and
certification including:
 Acoustic Signal Processor
 Microphones
 Water Sensors
 Water Sensor displays
 Digital Pressure Sensors
 Analog Vacuum Gauges
Tank Tightness Testing – Understanding the
Listing 3rd Party Listing of the EZY-3 Locator
Plus
Method is 3rd Party Approved by
Ken Wilcox, meets US EPA tank
tightness testing criteria to detect a
.1 gph leak and is currently listed
on the NWGLDE website:
http://www.nwglde.org/evals/esta
brook_ezy_check_d.html
 Non-Volumetric/Underfill Testing
Technology
 Vacuum method using acoustic
signal processor and microphone
to determine tank integrity by the
technician audibly listening for a
leak. The amount of vacuum
pulled on the tank in order to
properly test the tank is dependent
on site specific conditions including
the height of product in the tank
(inches), weight of fuel being
tested (psi) and water table
surrounding the tank

NWGLDE Listing Discussion
EZY-3 Locator Plus Operation





Tank must be shut down while
being tested
Acoustic portion of the test takes
only minutes to perform unless AHJ
requires minimum test periods
(background & test)
Single wall tanks in a dry
excavation and double wall tanks
with a dry interstitial space can be
tested rather quickly
If water table exists on a single
wall tank or if testing a double wall
tank with a brine-filled interstitial
area, test period must be extended
by performing a water intrusion
test in addition to the acoustic test
This method tests both the wetted
and dry portion of the tank
PRINCIPLE OF OPERATION
EZY 3 LOCATOR PLUS NON-VOLUMETRIC
TANK TESTING
The testing instrumentation provided to
the technician yields four very
important bits of information on the
underground tank.
• An acoustic signal, which reveals “no” sound,
and/or “no” water intrusion indicating a tight
tank.
• A leak in the ullage (dry) portion of the tank
that reveals a “hiss” sound.
• A leak below liquid level (wet) portion of the
tank that reveals a “bubbling” sound.
• The amount of water intrusion due to a leak.
Pros and Cons of the Method




PROS:
Completely dependent
upon the technician’s
discretion
Can test tanks with
minimal down time for the
owner
Very accurate in the
hands of a good
technician
SW tanks in a dry
excavation or DW tanks
with dry interstitial can be
tested quickly and
accurately
Cons:
 Completely dependent upon
the technician’s discretion
 Potential problems
associated with testing SW
tanks containing ethanol
blended fuel when a water
table is above tank bottom
or DW tanks with brine-filled
interstitial areas, or E-85
tanks
 Can be disastrous in the
hands of a poor or unethical
technician
Documentation Required by the Manufacturer for a
Test to be Considered Valid (Test Report)