Common
Problems found at UST Facilities during Inspections:
As an owner or operator of
underground storage tanks (USTs) storing petroleum or hazardous substances,
e.g. ethyl glycol (anti-freeze or coolant), xylene, acetone, alum, etc., you
must be knowledgeable of the key components of release detection for tanks and
piping, corrosion protection and record keeping in managing your USTs. The task of managing your tanks may seem
confusing; however, the following descriptions and photographs will give you
insight into the common issues inspectors find at UST facilities. These problems invariably result in penalties
and fines issued by the state or federal implementing agency to the owner or
operator of the facility.
Notification:
Release Detection:
Release detection is an essential
part of UST management. Release
detection is important in order to prevent fires and explosions due to
vapors in sewers and basements, and releases into the environment that can harm
groundwater resources. Release detection
is for both tanks and piping. A commonly
used Automatic
Tank Gauge system consists of a probe
permanently installed in the tank(s) and wired to a monitor
to provide information on product/water levels and temperature. ATG systems automatically calculate the
changes in product volume that can indicate a leaking tank. Some of the common problems found for release
detection for tanks during UST inspections are the following:
For Automatic Tank Gauges (ATGs)
Interstitial
Monitoring:
·
If
using an electronic
monitoring device, no record or monthly log of monthly monitoring results
are available at the time of the inspection.
·
Interstitial
probes are broken or inoperable.
Vapor Monitoring:
Though not commonly used, this
method is currently allowed under the federal UST regulations. Some common problems are found with the use
of this method. Vapor monitoring measures product vapors in the soil at the UST
site to check for a leak. A site assessment must determine the number and
placement of monitoring wells to make sure that a release is detected.
Groundwater Monitoring:
Inventory Control:
In conjunction with tank tightness
testing, this method will eventually be phased out as it can only be used for
ten years after the UST has been upgraded for spill, overfill and corrosion
protection (Most tanks were required to be upgraded by December, 1998).
However, common problems seen with this method are:
·
The measuring (or dipstick)
stick is broken or
rounded
at the end, or the stick markings are not discernable.
Statistical Inventory Reconciliation
(SIR)
In this method, a trained
professional uses sophisticated computer software to conduct a statistical analysis
of inventory, delivery, and dispensing data, which you supply regularly. This method of release detection can be used
for both tanks and product piping. However, SIR reports must say “pass” and not “failed”
or “inconclusive” in order to meet the monthly monitoring requirement for
release detection (see sample SIR report).
Release Detection for Piping:
Conducting release detection for
product piping is also vitally important to the proper management of your USTs.
Studies have shown that most releases
are caused piping by failures of both pressurized piping and suction piping
systems. In most instances, releases from buried piping
(and also from USTs) cannot be visually detected, which is why release
detection is so important. Some of the
common problems found during compliance inspections of product piping are:
·
Failure
to conduct annual line tightness tests of product piping and a functionality
test of the automatic line leak detector (ELLD
& ALLD)
for pressurized piping.
·
Failure
to conduct line tightness tests every three years for “American” type product line suction
systems. European or “safe” suction systems are not required to be tested
every three years.
·
Failure
to keep records of tightness tests until the next test is conducted.
·
Failure
to keep records of monthly “sensor
status” reports in systems that rely only on interstitial monitoring.
·
Failure
to install a line leak detector (LLD)
on systems using only interstitial monitoring.
Compliance problems are also found
in the inspection of the tank sump man-ways in which the product piping is
connected to the submersible pumps in pressurized systems. These problems are usually:
Spill and Overfill Prevention:
All USTs owners and operators must
take precautions to prevent the release of product to the environment. This is accomplished by the installation of
spill prevention equipment (spill
buckets) and overfill devices such as a “flapper
valve”, ball
float valve in the vent system or an audible or visible
alarm. Some common problems found
during compliance inspections for these regulatory requirements are:
Corrosion Protection:
Corrosion protection must be
provided for UST systems that are not constructed of non-corrosive materials,
e.g., composites, fiberglass, etc. Therefore,
all bare steel tanks, and other metal components of UST systems must be
protected from corrosion. Cathodic protection
systems, which include galvanic
and impressed
current systems, are generally designed by trained professional corrosion
engineers or experts to protect the
UST
systems from the effects of corrosion.
Some of the basic problems found during compliance inspections for this
regulatory requirement are:
·
Failure to have a certified technician inspect the cathodic protection system every
three years.
·
Failure
to keep records of the last two cathodic protection tests until the next test
is conducted.
·
For
impressed current systems, failure to check the impressed current system every
60 days and/or to provide electrical power to the impressed current system (the
rectifier
must be in the “On” position).
Record Keeping
Record keeping is vital in order to
demonstrate that your facility is in compliance with state and federal UST
regulations. As mentioned earlier, some
of the problems found with this requirement are:
·
Failure to keep all records of release
detection for tanks and piping, repairs and warranty claims.
·
Lack of record organization can greatly
increase the time of the UST inspection.
·
Records are not available at the
location or readily accessible at an alternate location.
·
Lack of knowledge by facility personnel
of the record keeping system or the record locations.