Transcript UNDERGROUND STORAGE TANKS

Underground Storage Tanks at
Duke
• Duke Medical Center
– 8 permitted USTs located on medical campus
– Range in size from 2,000 gallons to 30,000
gallons
• Proper management of these USTs will
hopefully prevent a future LUST or a large
surface spill of petroleum products
USTs at Duke
• Operating permits are required for all USTs
in NC (15A NCAC 2N)
– Associated yearly fee
– Compliance questionnaire must be completed
and signed before the permit will be issued.
UNDERGROUND STORAGE TANKS
• 40 CFR 280 - Technical Standards and
Corrective Action Requirements for Owners
and Operators of Underground Storage
Tanks (USTs).
Underground Storage Tanks
General Standards
• No person may install an UST system for
the purposes regulated substances unless the
UST system:
– will prevent releases due to corrosion or
structural failure;
– is cathodically protected against corrosion,
constructed of noncorrodible material, steel
clad with a noncorrodible material, or designed
to prevent the release of any stored substance;
and
Underground Storage Tanks
– Is constructed or lined with material that is
compatible with the stored substance.
• A UST system may be installed if a
corrosion expert determines that the site
will not be corrosive enough to cause a
release due to corrosion during operating
life.
Underground Storage Tanks
• Performance Standards for New UST
Systems
– Tanks and Piping
• must be properly designed and constructed, any part
underground must be protected from corrosion
• constructed of fiberglass reinforced plastic, or
• constructed of steel and cathodically protected in the
following ways:
– tank is coated with suitable dielectric material;
– field installed cathodic protection designed by expert;
– Impressed current systems are designed to allow
determination of current operating status and systems
maintained.
Double Walled Fiberglass Tank
Underground Storage Tanks
• constructed of steel fiberglass reinforced plastic
composite; or
• constructed of metal without additional corrosion
protection measures provided that
– corrosion expert determines corrosion at site is not a
hazard
– owners/operators maintain records that demonstrate
compliance with corrosion expert’s findings
– implementing agency determines tank construction and
corrosion protection sufficient to prevent the release or
threatened release of any stored regulated substance in a
manner that is no less protective of human health and the
environment
Underground Storage Tanks
– Spill and Overfill Protection
• to prevent spilling and overfilling associated with
product transfer to the UST system
owners/operators must use the following equipment:
– spill prevention equipment that will prevent a release of
product when the transfer hose is detached from the fill
pipe
– overfill prevention equipment that will:
» automatically shut off flow into the tank when the
tank is no more than 95% full, or
Underground Storage Tanks
» Alert the transfer operator when the tank is no more
than 90% full be restricting the flow into the tank or
triggering the high-level alarm, or
» restrict flow 30 minutes prior to overfilling, alert the
operator with a high level alarm one minute before
overfilling, or automatically shut off the flow into the
tank
• Owners/operators are not required to use spill and
overfill prevention equipment if alternated
equipment is used that is determined by the
implementing agency to be no less protective of
human health and the environment or the UST
system is filled by transfers of no more than 25
gallons at a time.
Underground Storage Tanks
– Installation
• All tanks and piping must be properly installed in
accordance with a code of practice developed by a
national recognized association or independent
testing laboratory and in accordance with the
manufacturer’s instructions.
– Certification
• owners/operators must provide certification of
compliance on the UST notification form
Installation of an
UST
Underground Storage Tanks
• Upgrading existing USTs
– Tank upgrading requirements
• tank may be upgraded to meet one of the following
requirements
– Interior lining - must be installed in accordance with
280.33 and within 10 years after lining and 5 years
thereafter, lining must be inspected and found to be
structurally sound
– Cathodic protection - must meet the requirements of
280.20(a)(2) and the integrity of the tank is ensured using:
» internally inspected and assessed to ensure the tank is
structurally sound and free of corrosion holes prior to
installation
Underground Storage Tanks
» tank had been installed for less than 10 years and is
monitored monthly for releases, or
» tank has been installed for less than 10 years and is
assessed for corrosion holes by conducting two
tightness tests that meet the requirements of
280.43(2). The first tightness test must be conducted
prior to installation of system. The second must be
conducted between 3 and 6 months following first
operation on the system, or
» tank is assessed for corrosion holes by a method that
is determined by the implementing agency to prevent
release
Underground Storage Tanks
– Internal lining combined with cathodic protection
» lining installed in accordance with 280.33
» cathodic protection system meets requirements of
280.20
– Piping upgrades
» metal piping that routinely contains regulated
substances and is in contact with the ground must be
cathodically protected .
– Spill and overfill protection
» must comply with the new UST system spill and
overfill prevention equipment requirements specified
in 280.20(2).
Underground Storage Tanks
– Notification Requirements
• Must notify state and local agency when bringing
tank system online and certification of compliance
with regulation
– NC UST Section Forms UST-6A/B, UST-15, etc.
• General Operating Requirements
– Owners/operators must ensure that releases due
to spilling or overfilling do not occur.
– Cathodic protection systems must be inspected
for proper operation by a qualified tester.
Underground Storage Tanks
• Compatibility
– Owners/operators must use an UST system
made of or lined with materials that are
compatible with the substance stored in the
UST system.
• Repairs Allowed
– Owners/operators must ensure that repairs will
prevent releases due to structural failure or
corrosion as long as the UST system is used to
store regulated substances.
Underground Storage Tanks
• Repairs to fiberglass-reinforced tanks may be made
by the manufacturer’s authorized representative
• Leaking metal pipes must be replaced. Fiberglass
pipes and fittings may be repaired.
• Repaired tanks and lines must be fit tested.
• Repaired tanks are internally inspected
• Repaired portion of tank must be monitored
monthly, or
• as specified by implementing agency
• Within 6 months following the repair of any
cathodically protected UST system must be tested in
accordance with the regulations to ensure proper
operation,
Underground Storage Tanks
• Owner/operators must maintain records of each
repair for the remaining operating life of UST
system.
• Release Detection
– must provide a method, or combination of
methods of release detection that:
• can detect a release from any portion of the tank and
the connected underground piping that routinely
contains product,
Underground Storage Tanks
• Is installed, calibrated, operated, and maintained in
accordance with the manufacturer’s instructions;
and
• meet the performance requirements in 280.43 or
2880.44.
• Any existing UST system that can not apply a
method of release detection must close the system.
• Methods
– Inventory control, manual tank gauging, tank tightness
testing, vapor monitoring, groundwater monitoring,
interstitial monitoring, line leak detectors
• Reference
• http://www.wastenotnc.org/ust/ust_main.html
– http://www.wastenotnc.org/ust/forms.html