EPA's Region 6 Office
Serving: Arkansas, Louisiana, New Mexico, Oklahoma, Texas, and 66 Tribal Nations
This guide will assist vehicle service facilities with the prevention and control of oil spills. Other guides have been developed to assist other industry sectors in the regulated community. This guide discusses the equipment and operating practices needed to meet the requirements of the Federal Oil Pollution Prevention Regulation found in Title 40 Code of Federal Regulations (CFR) Part 112, which includes the Spill Prevention Control and Countermeasure (SPCC) Plan requirements and the Facility Response Plan (FRP) requirements. The SPCC requirements are the focus of this guide; other guides are available for the facility response planning requirements (40 CFR 112.20 and 112.21) and general information on the Oil Pollution Prevention Regulation.
Recommended practices for pollution prevention and avoiding discharges
of oil are also included in this guide. These practices may also assist
facilities in achieving compliance with the SPCC requirements and reduce
the possibility of product loss and a discharge.
* A discharge is essentially a spill that reaches a navigable water or adjoining shoreline. The legal definition can be found in 40 CFR 112.2(b).
Applicability of the
SPCC Requirements to Vehicle Service Facilities
EPA's SPCC requirements (40 CFR 112.1 through 112.7) apply
to nontransportation-related facilities that could reasonably be expected
to discharge oil into or upon the navigable waters of the United States
or adjoining shorelines, and that have (1) a total underground buried
storage capacity of more than 42,000 gallons or (2)
a total aboveground oil storage capacity of more than 1,320
Some facilities may not be regulated if, due to their
location, they could not reasonably be expected to discharge oil into
navigable waters of the U.S. or adjoining shorelines. SPCC-regulated
facilities must also comply with other federal, state, or local laws,
some of which may be more stringent.
vehicle service facilities require the storage of oil products (e.g.,
motor oil, hydraulic oil, brake fluid, gasoline, and diesel) for maintenance
and fueling activities. These facilities range from small auto repair
shops and gas stations to truck repair garages and truck stops. It is
important for these facilities to recognize that they may be subject
to the SPCC requirements by either meeting the regulated aboveground
storage tank (AST) volumes or underground storage tank (UST) volumes.
In either case, if a facility is subject to SPCC, then all storage tanks,
both ASTs and USTs, at a facility are required to meet the spill prevention
measures prescribed in 40 CFR 112.7. For example, if a facility stores
over 42,000 gallons of product in USTs and in one 500-gallon AST, then
all tanks are subject. Conversely, if a facility stores product in one
1,000-gallon AST, then any USTs at the facility are also subject. Under
SPCC, tanks in vaults or partially buried tanks are considered to be
Although vehicle service facilities are subject to the SPCC requirements, they are usually not subject to the FRP requirements due to their storage capacities. However, all facilities must document this determination by completing the "Certification of the Applicability of the Substantial Harm Criteria Checklist," provided as Attachment C-II in Appendix C of 40 CFR 112. This certification should be kept with the facility's SPCC Plan.
SPCC and Specific
Spill Prevention Requirements for Vehicle Service Facilities
The owner or operator of an SPCC-subject facility is required to have a written site-specific spill prevention plan, which details how a facility's operations comply with the requirements of 40 CFR 112.
Requirements for specific elements to be included in the
SPCC Plan are found in 40
CFR 112.7. The SPCC Plan must be reviewed and certified by a Registered
Professional Engineer who is familiar with SPCC and has examined the
facility. To be in compliance, the facility's SPCC Plan must satisfy
all of the applicable requirements for drainage, bulk storage tanks,
tank car and truck loading and unloading, transfer operations (intrafacility
piping), inspections and records, security, and training. Most importantly,
the facility must fully implement the SPCC Plan. Newly constructed facilities
and facilities that make modifications must prepare or revise their
SPCC Plan within six months. Modifications may include, for example,
changes in piping arrangements or installation or removal of tanks.
SPCC requires containment of drainage from the operating
areas of a facility to prevent oil spills and contaminated runoff from
reaching storm drains, streams (perennial or intermittent), ditches,
rivers, bays, and other navigable waters.
Secondary containment and diversionary structures should
be in place to contain oil-contaminated drainage (e.g., rainwater) or
leaks around fuel dispensers, pipelines, valves, joints, transfer connections,
and tanks. For these purposes, facilities should use dikes, berms, curbing,
culverts, gutters, trenches, absorbent material, retention ponds, weirs,
booms, and other barriers or equivalent preventive systems.
SPCC requirements are performance-based, which permits
facility owners and operators to substitute alternative forms of spill
containment if the substitute provides substantially equivalent protection
against discharges to navigable waters to that provided by the systems
listed in 40 CFR 112.7(c). The secondary containment structure must
be impervious and must prevent water and fuel from percolating through
the soil, contaminating the soil and groundwater and possibly surfacing
aboveground into navigable waters or adjoining shorelines.
Substantially equivalent containment systems may be possible for AST systems (e.g., small double-walled ASTs equipped with spill prevention devices) that generally have capacities of less than 12,000 gallons. Alternative containment systems may not be appropriate for tank systems larger than 12,000 gallons or for systems that consist of several tanks connected by manifolds or other piping arrangements that would permit a volume of oil greater than the capacity of one tank to be spilled as a result of a single system failure.
Facilities most often use poured concrete walls or earthen
berms to contain drainage and provide secondary containment for storage
tanks and curbing and catchment basins for truck loading/unloading areas.
These contained areas are considered diked areas. Concrete and earthen
dike containment structures around storage tanks may accumulate significant
amounts of water. Drain lines, which must be watertight, are usually
installed through the dike walls and are used to drain accumulated stormwater
from the diked area. These lines should be fitted with valves or other
positive means of closure that are normally sealed closed and locked
to prevent any oil discharges from escaping the diked area. The valves
must be open-close manual valves; flapper valves are not acceptable.
These valves must be opened to drain rainwater and resealed
following drainage by trained and authorized facility personnel only.
Adequate records must be kept of such drainage events (i.e., date, time,
personnel names) and made part of the SPCC Plan. The accumulated rainwater
must be examined and determined to be free of oil contamination before
diked areas are drained. If any oil sheen or accumulation of oil is
observed, an alternate method of draining the diked area must be employed.
The contaminated water may be diverted to an onsite treatment plant
or oil-water separator; however, the adequacy of these systems is determined
on a case-by-case basis for each one's adherence to good engineering
practices and ability to retain a spill in the event of a system malfunction.
Vehicle service facilities may employ many different types
and designs of drainage control systems and oil-water separators. Facilities
must implement a system that is consistent with good engineering practices,
based on the size and complexity of their operations.
design may consist of a sump located inside a containment area, which
may be a blind sump (no drains) or a sump restrained by a normally closed
valve. Facilities may remove the floating oil product by manual skimming
or using sorbent materials. These materials must be disposed of properly
or recovered for reuse. Any oil removed from skimming or the sorbent
material must be disposed of as a waste oil. The remaining water in
the sump must be inspected before discharging it outside the containment
areas. Once sufficiently inspected and found to be free of oil, the
water may be discharged by authorized personnel as long as the discharge
is supervised and documented.
Other facilities may use a completely or partially buried
oil-water separator system equipped with an inlet valve and a weir and
baffle system, which directs the oil to one compartment and the water
to another. The oil-water separator must never automatically discharge
treated water to a sanitary sewer or anywhere outside a contained area.
Another alternative is to pump out diked areas with a
manual pump or vacuum truck. Any oil-contaminated water must be transported
to an appropriate waste-handling facility for disposal or treated on
Other operating areas of a vehicle service facility that
do not have secondary containment systems specifically designed for
those areas (otherwise referred to as "localized containment")
are considered undiked areas. Drainage must be controlled for these
areas: truck-to-tank filling sites (unloading), truck or engine washdown
areas, piping and manifold areas, garage bays, and fuel islands. All
undiked areas can be designed to control drainage through a combination
of curbing, trenches, catchment basins, and retention ponds, as necessary
to retain a spill. These structures must be inspected and examined for
integrity and their effectiveness. For example, if a paved area is improperly
graded or if a curb is deteriorating, contaminated water may escape
from the facility. For this reason, a Professional Engineer must certify
the SPCC Plan to ensure that the drainage system is adequately designed
and properly maintained in accordance with good engineering practices.
Whatever techniques are used, the facility's drainage
systems should be adequately engineered to prevent oil from reaching
navigable waters in the event of equipment failure or human error at
Many types of units are used to store oil products. Storage containers
or tanks may be located aboveground, underground, partially underground,
and inside buildings. At vehicle service facilities, storage units can
range in size from a few gallons to more than 20,000 gallons.
No tank should be used for the storage of oil unless its construction material is compatible with the material stored and conditions of storage such as pressure, physical and chemical properties, and temperatures.
It is recommended that the construction, materials, installation, and
use of tanks conform with relevant portions of industry standards, such
Petroleum Institute (API), National
Fire Protection Association (NFPA), Underwriters
Laboratory (UL), or American
Society of Mechanical Engineers (ASME), which may be required in
the application of good engineering practices or by state or local regulations.
All storage containers (e.g., tanks, oil-water separators) must have secondary containment for the entire contents of the largest single container within the containment area, plus sufficient freeboard to allow for precipitation. An alternative system could consist of a complete drainage trench enclosure arranged so that a spill could terminate and be safely confined in a catchment basin. The containment structure must be sufficiently impervious to the types of oil products stored at a facility. Diked areas should be free of pooled oil; spills should be removed promptly.
The volume of freeboard should be based on regional rainfall patterns.
Facilities in states with large amounts of rainfall (e.g., Washington,
Alaska, and Hawaii, and the Commonwealth of Puerto Rico) will require
secondary containment to accommodate greater amounts of water. Precipitation
data is available from the National Oceanic and Atmospheric Administration's
(NOAA) National Climatic Data Center (NCDC). The NCDC can be reached
by telephone at (828) 271-4800 and on the worldwide web at http://www.ncdc.noaa.gov/oa/climate/research/monitoring.html.
The following table describes the most common secondary containment systems.
|Secondary Containment Systems|
|Type of System||Description|
|Poured Concrete Walls||Poured concrete walls are strong, fairly watertight, and resistant
to petroleum penetration if adequately designed and maintained
according to good engineering practices.
|Containment Curbs||Containment curbs are similar to speed bumps and are often used
where vehicles need to access the containment area.
|Containment Pits/Trenches||Pits or trenches are belowgrade containment structures, which
may be covered with metal grates and lined with concrete.
|Earthen Berms||Earthen berms containing clay or bentonite mixtures are commonly
used at very large oil storage facilities.
|Concrete Block Walls||Concrete block walls are also commonly used for containment.
Tank Integrity - Inspections
ASTs should be properly maintained to prevent oil leaking
from bolts, gaskets, rivets, seams, and any other part of the tank.
The older riveted or bolted steel tanks tend to "weep" oil
from rivets and bolts. Personnel should note visible oil leaks on an
inspection form and report them to the person in charge of spill prevention.
Leaks should be repaired immediately. In some cases, the product in
the tank will require removal.
Another area of concern for ASTs is tank bottom deterioration.
Tank bottoms may be subject to extensive corrosion, which may not be
evident during visual inspections. Measures must be taken to prevent
this corrosion based on the type of tank installation and tank foundation.
Corrosion protection can be provided by dielectric coatings and carefully
engineered cathodic protection. Some facilities have installed double-bottom
tanks to reduce the corrosion factor.
Corrosion of a tank's surface may also result in tank
failure. Corrosion that is concentrated in small areas of a tank's surface
or "pitting" creates a high potential for tank failure. If
tanks are rusty, holes may form causing the tank to leak. Tank supports
and foundations should also be inspected for cracks, crumbling, deterioration,
ASTs should be subjected to periodic integrity testing. Some of the accepted methods for testing are the following:
- X-ray or radiographic analysis measures wall thickness and detects cracks and crevices in metal.
- Ultrasonic analysis measures shell metal thickness.
- Hydrostatic testing shows leaks caused by pressure.
- Visual inspection detects some cracks, leaks, or holes.
- Magnetic flux eddy current test used in conjunction with ultrasonic analysis detects pitting.
Internal Heating Coils
Internal steam-heating coils are sometimes used in heavy oil tanks to maintain the oil in a fluid, less viscous state in cold weather. The deterioration of the steam-heating coils from internal corrosion can result in product leakage when oil drains through a corroded coil to discharge into a nearby waterway. To control leakage through defective internal heating coils, the following factors should be applied:
- The steam return or exhaust lines from internal heating coils that discharge into an open water course should be monitored for contamination or routed to a settling tank, skimmer, or other separation system to remove oil;
- Consider using external heating coils and insulating the sides of the tank if necessary. Because of the problems encountered with internal steam-heating coils, there has been a movement away from their use to more modern external heat-exchanger systems.
Fail-Safe Devices - Level
Gauging Systems and Alarms
Vehicle service facilities must take precautions to ensure that tanks are not overfilled. There are two basic objectives for using a fail-safe system:
prevent the tank from overfilling and spilling liquid.
prevent damage to the tank.
Level gauging systems must be selected in accordance with good engineering practices based on the size and complexity of operations at a facility. It is not adequate to only "stick" a tank. A second overfill protection measure should be used as a backup. Some trucks have automatic shutoff systems, which shut off the pump once the meter reaches the volume of product that has been determined to be a safe fill level (e.g., 90% of capacity). Larger tanks may be designed with gauges, high-level alarms, and high-high level alarms to satisfy this requirement. The following table provides examples of some acceptable systems.