SPCC Requirements and Pollution Prevention Practices for Oil Production, Drilling and Workover Facilities

Overview

This guide will assist oil production, drilling and workover 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.

Applicability of the SPCC Requirements to Oil Production, Drilling, and Workover 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 gallons, or (3) an aboveground oil storage capacity of more than 660 gallons in a single container.

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.

An onshore production facility may include all wells, flowlines, separation equipment, storage facilities gathering lines, and auxiliary nontransportation-related equipment and facilities in a single geographical oil or gas field operated by a single operator. An offshore oil drilling production, or workover facility may include all drilling or workover equipment, wells, flowlines, gathering lines, platforms, and auxiliary nontransportation-related equipment and facilities in a single geographical oil or gas field operated by a single operator.

Many oil drilling and production facilities are subject to the SPCC requirements, and some may be subject to the Facility Response Plan (FRP) requirements under 40 CFR 112.20 and 112.21 and associated appendices. All owners or operators of SPCC-regulated facilities should determine whether the facility poses a threat of substantial harm to the environment. As outlined in 40 CFR 112.20(f)(1), a facility has the potential to cause substantial harm if:

• The facility lacks secondary containment able to contain the capacity of the largest AST within each storage area plus freeboard to allow for precipitation;
• The facility is located at a distance such that a discharge from the facility could cause injury to an environmentally sensitive area;
• The facility is located at a distance such that a discharge from the facility would shut down a public drinking-water intake; or
• The facility has had a reportable spill greater than or equal to 10,000 gallons within the last five years.

All facilities must document the determination of substantial harm 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. Click here for more information on navigable waters and oil.

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 of all operating areas (e.g., oil production, oil drilling, and workover facilities), containment for tank batteries and central treating stations, bulk storage tanks, unloading and loading areas, 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 from all tank battery and central treating plant installations. 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).

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.

Secondary Containment Systems

Dirt berms or retaining walls are commonly employed for secondary containment purposes, especially at very large oil storage tank farms where installing concrete retaining walls would be too expensive. Field production facilities almost always utilize dirt berms for containment purposes, due to the availability and cost effectiveness of dirt in production areas. If dirt berms are used, they should contain some clay and be compacted. Limitations of using dirt for building secondary containment structures are:

Some facilities may use concrete blocks to build secondary containment structures. Concrete blocks may not be sufficient for this purpose for the following reasons:

• Settling eventually separates or cracks the blocks and destroys the integrity of the wall.
• Concrete blocks are very porous and do not establish liquid-tight seals between mortared joints.
• Water and ice penetrate the blocks and eventually break them apart due to the freeze-thaw expansion properties of water.

If concrete is used to build secondary containment structures, then poured concrete walls are the preferred method. Poured concrete containment systems are very strong, fairly watertight, and resistant to petroleum penetration. It should be stressed that conventional concrete is not totally impervious to petroleum, and any spill left inside a containment area may eventually penetrate the concrete and conceivably contaminate groundwater sources. Therefore, spills inside diked areas should be cleaned up as soon as possible.

Whatever material or method is employed for secondary containment, it must hold the entire contents of the largest tank located in the containment structure. The containment structure must be sufficiently impervious to contain spilled oil. Diked areas should be free of pooled oil; spills should be removed promptly.

Tank batteries and central treating stations, which may use any of the secondary containment systems listed in the above section, should have drains closed and sealed at all times except when rainwater is being drained. Prior to drainage, the diked area must be inspected to ensure that:

Accumulated oil on the water should be picked up and returned to storage or disposed of in accordance with approved methods.

Field drainage ditches, road ditches, and oil traps, sumps or skimmers, if such exist, should be inspected at regularly scheduled intervals for accumulation of oil that may have escaped from small leaks. Any such accumulation should be removed.

Tank Material

Most production storage tanks are constructed of welded, riveted, or bolted steel. Fiberglass tanks are commonly used for storing saltwater (brine). Most steel tanks are provided with removable clean-out plates which allow workers to enter the tanks and clean them or perform repairs. Most tanks require periodic cleaning due to paraffin (a wax-like hydrocarbon) deposits and sediment accumulation. The gasket located between the clean-out plate and tank is a common source of leakage and should be periodically checked, repaired, or replaced as necessary.

Wooden tanks cannot be repaired if they are leaking, rotten, or lack structural integrity. Evidence of fresh oil-saturated soil or pooling oil around the tank is an adequate indication of leakage. Since leaking wooden tanks cannot be repaired, they need to be taken out of service.

No tank should be used for the storage of oil unless its material and construction are compatible with the material stored and the conditions of storage.

Secondary Containment

All tank battery and central treating plant installations should be provided with a secondary means of containment for the entire contents of the largest single tank, if feasible, or an alternate system, such as those outlined in 40 CFR 112.7(c)(1).

Drainage from undiked areas should be safely confined in a catchment basin or holding pond. This may not be practical for a production facility due to terrain, weather, or the location of the undiked areas. In such cases, a production facility owner may want to substitute a contingency plan which designates equipment and manpower to control, contain, and clean up a spill in this area, in lieu of using secondary containment.

Visual Inspections

On a scheduled periodic basis, all tanks that are used for oil storage should be visually examined by a competent person for condition and need for maintenance. Such examination should include the foundation and supports of tanks that are above the surface of the ground. There should be no large gaps between the foundation and the tank bottom or between the ground surface and the tank bottom (if the tank sits directly on the ground). Concrete foundations should not be crumbling or excessively cracked. Storage tank foundations should provide adequate support for tanks.

ASTs should be properly maintained to prevent leakage of oil through bolts, gaskets, rivets, seams, and any other part of the tank. Tanks should be structurally intact, with no cracks, holes, or leaks.

Oil storage tanks should be maintained and free of excessive rust and exterior corrosion. Excessive rust or corrosion may be identified by pitting or flaking on steel surfaces. A good maintenance program will provide for periodic cleaning and painting of tanks.

Fail-Safe Engineering

New and old tank battery installations should be fail-safe engineered or updated to prevent spills. Consideration should be given to one or more of the following:

All aboveground pipes and valves should be regularly examined on a scheduled basis by trained personnel. Flange joints, valve glands and bodies, supports, and metal surfaces should be evaluated. Any defective or leaking equipment should be replaced or repaired. Pumping well polished rod stuffing boxes should be examined often, because leaks can develop quickly when stuffing boxes lose their seals due to friction from contact with the moving polished rod.

Off-load lines or sales outlet connections used for tank truck transfers of crude oil should have valves closed and outlets capped when not in use. Drip pans or buckets should be placed below the outlet or connection to catch small spills or leaks of oil.

Brine Disposal

Saltwater (brine) disposal facilities should be examined often to detect system upsets that could cause an oil discharge, particularly following sudden changes in atmospheric temperature.

Flowline Maintenance

Production facilities should have a program of flowline maintenance to prevent spills from this source. The program should include periodic examination and corrosion protection. Flowlines should be repaired or replaced as necessary.

Adequate records should be made of such repairs, kept for a minimum of three years, and made part of the SPCC Plan.

Mobile drilling or workover equipment should be positioned or located so as to prevent spilled oil from reaching navigable waters.

Depending on the location of the well, catchment basins or diversionary structures (i.e., ditches, berms, walls, etc.) may be necessary to intercept and contain spills of fuel, crude oil, or oily drilling fluids.

Before drilling below any casing string or during workover operations, a BOP assembly and well control system should be installed that is capable of controlling any wellhead pressure that could be encountered while the BOP assembly is on the well. Casing and BOP installations should be installed in accordance with state regulatory agency requirements.

Oil drainage collection equipment must be used to prevent and control small oil spillage around pumps, glands, valves, flanges, expansion joints, hoses, drain lines, separators, treaters, tanks, and allied equipment. Drains on the facility should be controlled and directed toward a central collection sump or equivalent collection system sufficient to prevent discharges of oil into navigable waters. Where drains and sumps are not practicable, oil contained in collection equipment should be removed as often as necessary to prevent overflow.

For facilities employing a sump system, sump and drains should be adequately sized and a spare pump or equivalent method should be available to remove liquid from the sump and assure that oil does not escape. A regularly scheduled preventive maintenance inspection and testing program should be employed to assure reliable operation of the liquid removal system and pump startup device. Redundant automatic sump pumps and control devices may be required on some installations.

In areas where oil-water separators and heater-treaters are equipped with dump valves, which fail most often in the closed position creating a high pollution risk, the facility must be specially equipped to prevent the escape of oil. This could be accomplished by extending the flare line to a diked area if the separator is near shore, equipping it with a high liquid-level sensor that will automatically shut in wells producing to the separator, parallel redundant dump valves, or other feasible alternatives to prevent oil discharges.

Atmospheric storage or surge tanks should be equipped with high liquid-level sensing devices or other acceptable alternatives to prevent oil discharges. Pressure tanks should be equipped with high and low pressure sensing devices to activate an alarm or control the flow or with other acceptable methods to prevent oil discharges.

Tanks should be equipped with suitable corrosion protection. A written procedure for inspecting and testing pollution prevention equipment and systems should be prepared and maintained at the facility. Such procedures should be included as part of the SPCC Plan.

Testing and inspection of the pollution prevention equipment and systems should be conducted by the owner or operator on a scheduled periodic basis in accordance with applicable regulations commensurate with the complexity, conditions and circumstances of the facility.

Surface and subsurface well shut-in valves and devices in use at the facility should be sufficiently described to determine method of activation or control (e.g., pressure differential, change in fluid or flow conditions, combination of pressure and flow, manual or remote control mechanisms). Detailed records for each well, while not necessarily part of the plan, should be kept by the owner or operator.

Before drilling below any casing string and during workover operations, a blowout preventer (BOP) assembly and well control system should be installed that are capable of controlling any wellhead pressure that is expected to be encountered while that BOP assembly is on the well. Casing and BOP installations should be installed in accordance with state regulatory agency requirements.

Extraordinary well control measures should be provided that would address emergency conditions, including fire, loss of control and other abnormal conditions. The degree of control system redundancy should vary with hazard exposure and probable consequences of failure. It is recommended that surface shut-in systems have redundant or ''fail close'' valving. Subsurface safety valves may not be needed in producing wells that will not flow but should be installed as required by applicable state regulations.

To eliminate any potential for misunderstandings, written instructions should be prepared by the owner or operator for contractors and subcontractors to follow whenever contract activities include servicing a well or systems appurtenant to a well or pressure vessel. Such instructions and procedures should be maintained at the offshore production facility. Under certain circumstances and conditions, such contractor activities may require the presence at the facility of an authorized representative of the owner or operator who would intervene when necessary to prevent a spill.

All manifolds (headers) should be equipped with check valves on individual flowlines.

If the shut-in well pressure is greater than the working pressure of the flowline and manifold valves up to and including the header valves associated with that individual flowline, the flowline should be equipped with a high pressure sensing device and shut-in valve at the wellhead unless provided with a pressure relief system to prevent overpressuring and system failure.

All pipelines appurtenant to the facility should be protected from corrosion. Methods used, such as protective coatings or cathodic protection, should be discussed in the SPCC Plan.

Submarine pipelines appurtenant to the facility should be adequately protected against environmental stresses and other activities, such as fishing operations. They should be in good operating condition at all times and inspected on a scheduled periodic basis for failures. Such inspections should be documented and maintained at the facility.

Wellheads and Christmas Trees

Flowing and pumping wells should be maintained and inspected for leaks and possible sites of failure. This means that wellheads (both casing heads and tubing heads), christmas trees, and associated valves, fittings, and pressure gauges should be inspected and repaired as necessary. Leaks which have saturated the soil should be stopped and any accumulations of oil removed. Oil-saturated soil is often removed or remediated in accordance with state regulations.

Separators, Heater-Treaters, and Other Process Vessels

Separators, heater-treaters, and other process vessels are susceptible to many of the same corrosion and leakage problems as petroleum storage tanks. Concrete foundations crack, crumble, and deteriorate, and vessel bases, flowlines, valves, joints, and pressure gauges corrode and leak if not properly maintained.

If present, concrete foundations of separators should be structurally sound and capable of providing adequate support for the separator. Separator vessels themselves should be free of extensive corrosion, cracks, or leaks. Flowlines, dump valves, joints, and gauges should be adequately maintained and free of leaks and drips. Dump valves commonly malfunction and should be checked. Soil beneath separators should not be saturated with oil. Adequate secondary containment must be provided to contain spills. This can be provided in the form of a dike or berm, or a drainage system which flows into a holding pond or basin to catch and contain a spill.

The containment system must be large enough to hold the contents of the largest process vessel or storage tank.

Flarelines

Flarelines are sometimes used to vent excess gas pressure from heater-treater (separator) units to a site away from the tank battery. These flarelines are a source of occasional spillage when the dump valve located on the separator malfunctions and oil is forced out the flareline and onto the ground outside the retaining berm. If there are indications of spillage, such as oil stains, or pooled oil under flarelines, flarelines should be provided with secondary containment in the form of sumps, dikes, or retention ponds.

Oil production facilities are subject to the same inspection and record keeping requirements as bulk oil storage facilities regarding diked area drainage, transfer operations, and flowline maintenance. Tanks, separators, supports and foundations must be visually examined on a scheduled periodic basis and adequate records must be kept.

Records of inspection procedures, maintenance, and draining of diked areas should be included in the facility's SPCC Plan, and must be kept for a minimum of three years.

Oil production facilities are subject to the same requirements regarding personnel training in spill prevention as bulk oil storage and handling facilities.

A large number of spills are caused by operator error; therefore, training and briefings are important for the safe and proper functioning of a facility. Training encourages up-to-date planning for the control and response to a spill and an understanding of the facility's spill prevention controls and SPCC Plan. Regular safety and spill prevention briefings should be held to facilitate discussions of spill events or failures, malfunctioning equipment, and recently developed precautionary measures. Also, one person must be designated accountable for spill prevention at the facility.

Owners and operators are responsible for properly instructing drivers, tank gaugers, pumpers, and any other operating personnel involved in oil operation systems in the operation and maintenance of equipment to prevent the discharge of oil and applicable pollution control laws, rules and regulations. All employees should be familiar with the SPCC Plan and where it is kept, or have a copy of the Plan available for their use.

Records of employee training and spill prevention briefings for personnel should be included in the SPCC Plan and kept for a minimum of three years. Click here for more information on the Owner/Operator Relationship.

There are a variety of ways for a facility to be designed and constructed to achieve compliance with the SPCC requirements. Facilities may differ greatly in the types of diversionary structures and spill control equipment employed. Facilities should also consult industry associations, which specifically identify technical and engineering standards for the design and construction of tanks and pipelines; cathodic protection of tanks and pipelines; AST tank bottom liners; tank inspection, repair, alteration, and reconstruction; tank cleaning; and tank overfill protection. These standards may assist the facility in identifying good engineering practices and achieving compliance with the SPCC requirements.

Acknowledgments

We would like to acknowledge Richard Franklin, U.S. EPA Region VI, for his valuable assistance in the preparation of this guide. The following publication also provided valuable assistance:

U.S. Environmental Protection Agency, 1995. SPCC/OPA Manual. U.S. EPA Region VIII, Ecosystem Protection and Remediation Preparedness Team. Denver, Colorado.