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40 CFR 112

Prepared By Environmental Protection Agency
Emergency Response
Region 6
1445 Ross Ave (6E-EP)
Dallas, TX 75202
Don Smith
(214) 665-6489


The Environmental Protection Agency Oil Pollution Prevention Regulation, published in the Federal Register on December 11, 1973, is addressed to non-transportation related facilities and is further identified as Title 40, Code of Federal Regulations, Part 112. The main requirement of facilities subject to the regulation is the preparation and implementation of a plan to prevent any discharge of oil into waters of the United States. The pan is referred to as a Spill Prevention Control And Countermeasures Plan (SPCC).

The following discussion will answer some the frequently asked questions and summarize key elements of the regulation.


To prevent discharges of oil into waters of the United States. The main thrust of the regulation is "prevention" as opposed to "after-the-fact," or "reactive" measures commonly described in Spill Contingency Plans.


Owners or operators of facilities engaged in drilling, producing, gathering, storing, processing, refining, transferring, or consuming oil and oil products, providing;

  1. the facility is non-transportation related (see definition of non-transportation)
  2. aboveground storage capacity of single container is in excess of 660 gallons, or an aggregate storage greater than 1320 gallons, or providing that total below ground storage capacity is greater than 42,000 gallons
  3. facilities, which, due to their location could reasonably expect spilled oil to reach waters of the United States.


Requires facilities which are subject to the regulation (based on above criteria) to prepare and implement a Spill Prevention Control and Countermeasure (SPCC) Plan, prepared in accordance with guidelines outlined in paragraph 112.7 of the regulation.


  • Owners - operating their own facilities, or
  • Operators - of leased facilities, or
  • Persons in Charge - including departments, agencies, and instrumentalities of State or Federal Government.


  1. The SPCC Plan shall be a carefully thought out plan, prepared in accordance with good engineering practices, and which has the full approval of management at a level of authority to commit the necessary resources.
  2. The complete SPCC Plan shall follow the sequences outlined (paragraph 112.7 of the regulation), and include a discussion of the facility's conformance with the appropriate guidelines listed.


  1. The Plan must be certified by a registered professional engineer (see paragraph 112.3(d) of the regulation).
  2. A complete copy of the SPCC Plan shall be maintained at the facility, if the facility is normally attended at least eight hours per day, or at the nearest field office if the facility is not so attended. The plan is only submitted to EPA or State Agencies under circumstances and conditions outlined in paragraph 112.3(f) and paragraph 112.4(a).
  3. The SPCC Plan shall be made available to the EPA Regional Administrator, or to his duly authorized representative for on-site review during normal working hours.
  4. If a discharge occurs - in excess of 1,000 gallons in a single event, or two discharges occur in "harmful quantities" within any twelve month period, the owner/operator must then submit copies of the SPCC Plan to the Regional Administrator and to the State Agency in charge of water pollution control activities. Other information must accompany the SPCC Plan as outlined in paragraph 112.4(a).
  5. After review of the SPCC Plan submitted under these circumstances the Regional Administrator may require an amendment to the Plan as deemed necessary to prevent any future discharges.


For Existing Facilities:
From the effective date of the regulation (January 11, 1974)
Six months to prepare SPCC Plan (to July 11, 1974)


Twelve months to implement SPCC Plan (to January 11, 1975)

For New Facilities: From time of start-up of the new facility -
Six months to prepare SPCC Plan preparation
Twelve months to implement


At this point in time, (3-17-75), the only provision of the regulation for time extension of SPCC Plans would apply to NEW FACILITIES.

As an interpretative comment - it is difficult to anticipate circumstances which would reasonably justify an extension of time for a new facility since the normal time provision begins at the start-up date.


  • What facilities will be subject to the 40 CFR 112 Regulation?
  1. Aboveground storage capacity in excess of 1,320 gallons or a single container in excess of 660 gallons
  2. Underground storage capacity in excess of 42,000 gallons.
  3. Facilities which due to their location and capacities in 1 and 2 could reasonably be expected to discharge into waters of the United States if a spill should occur.
  • What is considered a non-transportation related facility?

 All fixed facilities including support equipment, but excluding interstate pipelines, railroad tank cars in route, transport trucks in route and terminals associates with the transfer of bulk oil to or from a water transportation vessel.

Question - Who determines if a facility is in need of a Plan?

Answer - The owner or operator as required by the Regulation.

Question - What determines reasonability?

Answer - Location of the facility in relation to a stream, ditch, storm sewer, distance, volume of material, drainage patterns, soil conditions, etc.

Question - Who is required to prepare the SPCC Plan?

Answer - The owner/operator. The Certifying Engineer may assist, but the owner/operator is responsible.

Question - Why does the Plan have to be certified?

Answer - To assure that good engineering practices are followed in preparing the plan.

Question - What are the requirements for certification?

Answer - The engineer should be familiar with the provisions of 40 CFR 112 and must have examined the facility -


be registered in at least one State. It is not necessary to be registered in the State in which the facility is located.

Question - What constitutes an SPCC Plan?

Answer - Follow the guidelines suggested in the Regulation - paragraph 112.7.

A sketch or drawing of the site will assist in identification the implementation.

Question - When the SPCC Plan is completed and certified, is it sent to EPA for review?

Answer - No, a certified copy of the Plan is required to be available from EPA on-site review; if the facility is attended at least eight hours a day. If the facility is not attended, then the Plan shall be kept at the nearest company office.

Question - What is the time frame for plan preparation and implementation for a new facility?

Answer - One year from the date the facility begins operation.

Question - Is an SPCC Plan required when a facility has existing preventative systems in place and no previous history of spills?

Answer - The need for an SPCC Plan is determined by criteria; the storage capacity and the location, disregarding existing manmade structures.

Question - When a production lease consists of several operations, such as wells, oil/water separators, collection systems, tank batteries, etc. does each operation require a separate SPCC Plan?

Answer - No, one SPCC Plan may include all operations within a single geographical area when each is addressed in the Plan.

Question - Is every loss of oil or oil product subject to a penalty?

Answer - No, a discharge is defined in 311(a)(2) of the Federal Water Pollution Control Act as including, but not limited to, any spilling, leaking, pumping, pouring, emitting, emptying, or dumping that enters the waters of the United States or on the adjoining shorelines in harmful quantities. If the water is affected, a penalty could be assessed if a spill occurs and is prevented by some means from entering water, no penalty should be assessed.

Question - What is considered to be a harmful quantity?

Answer - Harmful quantity is defined in the Regulations as discharges which affect the water quality standards or cause a film or sheen upon or discoloration of the water or adjoining shorelines.

Question - What are considered navigable waters?

Answer - Section 502(7) of the EWPCA defines navigable waters as the waters of the United States. The Coast Guard interpretation includes not only the traditionally recognized navigable waters but all streams, creeks, lakes, and ponds connected to the tributary system in a river basin.

Question - Is one spillage of oil into a municipal storm sewer a violation?

Answer - If oil reaches "navigable water" a violation has occurred and penalties may result. The facility spilling the oil must also have an SPCC Plan implemented. A properly engineered plan and implemented would prevent a spill from occurring.

Question - What penalties are assessed?

Answer - Paragraph 112.6 of 40 CFR 112 authorizes the Regional Administrator to assess a civil penalty up to $5,000 per day for each violation.

Question - Must secondary containment be provided for transfer operations (i.e. for a tanker truck loading or unloading fuel at a facility?

Answer - The secondary containment system should be designed to hold at the least maximum capacity of any single compartment of a tank car or tank truck loading or unloading at the facility. This is not to say that a truck must park within a diked wall for loading/unloading. The regulation allows flexibility here for diversion structures such as curbing or diking to channel a potential spill to a secondary containment structure.

Question - Must an SPCC Plan be sent to EPA for review and/or approval?

Answer - Normally an SPCC Plan is not required to be sent to EPA for approval; however the owners or operators of a facility is required to maintain a complete copy of the Plan at the facility if the facility is normally attended to at least eight hours per day, or at the nearest field office if the facility is not attended. Upon inspection by EPA or representative, a SPCC Plan must be produced for the inspection review. A SPCC Plan must be submitted to EPA for review if either of the following conditions are met: (1) A facility discharges 1,000 gallons or more of oil in a single spill event, (2) a facility discharges oil in harmful quantities as defined in 40 CFR 110 into any waters of the United States in two spill events, reportable under section 311(b)(s) of the Federal Water Pollution Control Act; occurring within any twelve month period. If either conditions applies, the owner or operator of such facility is required to submit their SPCC Plan to the EPA within 60 days for review.

Question - Are SPCC Plans required for hazardous substances or hazardous wastes?

Answer - SPCC Plans are required for facilities that store or transport oil of any kind or in any form, including, but not limited to petroleum, fuel oil, sludge, oil refuse and oil mixed with wastes other than dredged soil.

The SPCC regulation, as written does not apply to hazardous substances or hazardous waste. Some RCRA permits may require secondary containment for hazardous wastes on a facility specific basis. Although secondary containment is not required by regulation for hazardous substances, EPA recommends that facility owners strongly consider it as a means of reducing environmental damage and liability resulting from an accidental release.

Question - Is a facility required to develop a SPCC Plan if a spill from the facility is not able to reach any navigable waters of the United States?

Answer - A SPCC Plan is required for any facility which, due to it's location, could reasonably be expected to discharge oil in harmful quantities, as defined in 40 CFR Part 110, into or upon the waters of the United States. The determination to develop a SPCC Plan is the responsibility of the owners or operators of the required facilities.

Question - Are federally-owner facilities subject to SPCC requirements?

Answer - Federally-owned and operated facilities are required to develop a SPCC Plan for any federal facility that meets the applicability requirements.

Question - Do the SPCC regulations spell out design requirements for diking, curbing, etc.?

Answer - The SPCC regulations requires diked areas for storage tanks to be sufficiently impervious to contain any spilled oil. All bulk storage tank installations should be constructed so that a secondary means of containment is provided for the entire contents of the largest single tank plus sufficient freeboard to allow for precipitation. Containment curbs and pits are sometimes used as secondary containments but they may not always be appropriate for some facilities.

Question - What authorities do states have under the SPCC regulation?

Answer - The SPCC Program is a federally mandated program. Executive Order 11735 (August 3, 1973) delegated the authority of the President to promulgate prevention regulations for vessels or transportation, and to EPA (The Regional Administrators) for prevention for transportation related and non-transportation related facilities. States may perform SPCC inspection at the request of EPA; however, the overall review process of the inspection is the responsibility of the EPA. This review process will be handled within the Regional EPA office.

Question - If a tank is taken out of service, what measures must a facility take in order to be exempt from SPCC regulations?

Answer - Any tank taken out of service must have all pipes and fittings sealed off and tanks should be filled with an inert material, such as sand or concrete in order to be exempt from the SPCC regulations.

Question - Are tanks-within-a-tank satisfactory to meet the secondary containment requirement for SPCC?

Answer - Tanks-within-a-tank may provide adequate secondary containment; however, the valving must be designed so that accidental release from the inner tank (from such occurrences as an inadvertent valve opening or a failure) are completely contained within the outer tank.

Question - Must each tank in a tank battery have secondary containment?

Answer - A dike for tank battery is required to contain only the largest single tank within the tank battery plus sufficient freeboard to allow for precipitation. The dike should be sufficiently impervious to contain any spilled oil from the tank battery.

Question - Should above ground tank and underground tanks be subject to inspection?

Answer - All above ground tanks should be subject to periodic integrity testing, taking into account tank design and using such techniques as hydrostatic testing, visual inspection or a system of non-destructive shell thickness testing. Tank supports and foundations should be included in these inspections.

Buried storage tanks represent a potential for undetected spills. A new buried installation should be protected from corrosion by coatings. Buried tanks should be at least be subject to regular pressure testing. To qualify as buried storage, a tank must be completely buried in the earth. Tanks which are in an underground basement or vault do not qualify for underground storage. The reason is that buried tanks usually have some inherent protection by the containment action of the surrounding earth.

Question - Are transformers covered under SPCC regulation?

Answer - Electrical transformers and similar equipment are covered by the SPCC regulation provided that they contain sufficient quantities of oil, and due to location, can reasonably be expected to spill their oil into navigable waters or adjourning shorelines.

Question - If the drainage from a facility discharge into a sewer system is this facility required to have a SPCC Plan?

Answer - If the sewer is a storm sewer or combined sewer, the spill could reasonably be expected to reach navigable waters and thus the plan would be required. If the flow from the sewer is entirely treated in a sewage treatment plant then an engineering assessment should be made by the owner or operator as to whether or not the treatment system could handle the possible volume of oil without exceeding the permitted amount in the plant discharge without causing a harmful discharge. If the system could not handle the oil, then a SPCC Plan would be required.

Violations of other sections of the Federal Water Pollution Control Act or other laws may be involved in a spill to a municipal sewer system.

Question - What other regulation or standards may be applicable for oil storage facilities?

Answer - UST (Underground Storage Tank), NFPA (National Fire Prevention Association) and State Fire Marshals.

Disclaimer: This is by no means a comprehensive list of other applicable regulations and standards.

If you have additional questions about the SPCC Regulation, please contact the United States Environmental Protection Agency at (214)855-0711.



There is no rigid format for an SPCC Plan. The guidelines (paragraph 112.7) of the regulation suggesting format is quoted - "The complete SPCC Plan shall follow the sequence outlined below, and include a discussion of the facility's conformance with the appropriate guidelines listed." These guidelines indicate "minimal" requirements and must necessarily provide wide latitude to the many types of facilities to which they apply.

Spills can best be controlled by installation of prevention systems, adherences to proper operating procedures, and preventative maintenance, supported by positive containment and removal. If these elements are well thought out and documented, the result will be an adequate SPCC Plan. Therefore, three basic principals should be embodied within a SPCC Plan -

  1. The practices devotes to the prevention of oil spills,
  2. the plan of containment should a spill occur, and
  3. the plan for removal and disposal of oil.

Furthermore, the Plan must be maintained and/or revised according to any changes in operation, process, or facilities covered.


Operational errors and equipment failures are the primary causes of spills. Therefore, the Plan should contain measures designed to avoid these errors and failures.

Operational Errors can be minimized through -

  1. Personnel training,
  2. operator awareness of the imperative nature of spill prevention, and
  3. adequate supervision of procedures.

Management must be committed to spill prevention and must develop and enforce techniques for safe and efficient operation.

Equipment Failures can be minimized through -

1. proper initial selection and construction,
2. maintenance of structural integrity and function, and
3. frequent inspections.


Industry standards and sound engineering practices dictate the proper course of action in each of these areas.


In our "inland" region we are generally concerned with spills from facilities where positive containment devices and systems are practical and effective. Dikes, retaining walls, curbing, spill diversion ponds, sumps, etc. fall into the category of prevention systems. Only where impracticability* to provide containment can be clearly demonstrated does the facility have the option to take the "contingency" plan approach. Contingency plans are considered "reactive" in nature - that is, they generally describe after-the-fact actions and can only be expected to mitigate the effects of a spill after it occurs. Therefore, preventive systems must be given first priority consideration in the initial study and preparation of the SPCC Plan.

* "Impracticability to provide positive containment" alludes mainly to those cases where severe space limitations may preclude installation of structures or equipment to prevent oil from reaching water. Justifying "impracticability" on the basis of financial considerations is difficult because the required commitment of man-power, equipment, and materials to expeditiously control, remove, and disperse of spilled oil would not normally offer any significant economic advantage.



While each SPCC Plan is unique, there are certain elements which may be included almost without exception to make a plan comply with provisions of the regulation and the spirit of oil spill prevention. These elements are discussed or listed as follows:

Name of Facility - This may or may not be the business name.
Type of Facility - This briefly describes the business activity.
Date of Initial Operation - The date that the facility began operation.
Location of Facility - This may be a word description, or city address which can be supported by area maps.
Name and Address of Owner - Usually an address remote from the facility location.
Designated Person Responsible for Oil Spill Prevention - Each facility should have some person with overall oil spill responsibility. This person should be thoroughly familiar with the regulation and the facility SPCC Plan.
Oil Spill History - This section can be either a reactive declaration, or a detailed history of significant spill events which occurred in the twelve month period prior to the publication of the regulation. In the latter case, typical information would include:

1. type and amount of oil spilled

2. location, date and time of spill(s)

3. watercourse affected

4. description of physical damage

5. cost of damage

6. cost of cleanup

7. cause of spill

8. action taken to prevent recurrence


Management Approval - This is a signed statement of a person with the authority to commit management to implementation of the Plan.

Certification - This is a statement of plan certification under the seal, signature, State and registration number of a registered professional engineer. The certifying engineer is not necessarily registered in the State in which the facility is located.

NOTE: All of the above information may be presented on a single page of an SPCC Plan. As an example, in Appendix "A" is a sheet entitled "Certification Information."

Facility Analyses - A portion of the plan should include a description of facility operation which would generally indicate the magnitude of spill potential. For example, the amount and type of storage, normal increments of transfer or patterns of spilled oil should be indicated along with any factors which are pertinent or influence spill potential. It is appropriate to support this type of information by charts, tables, plot plans, etc. to aid clarity or promote brevity.

Location of Facility - The geographical location is an integral part of the SPCC Plan. Location and topographic maps can be critical in determining the adverse consequences of an oil spill. Sources for such maps include (1) U.S. Geological Survey, (2) State Highway Department, (3) County Highway Engineer, (4) Local Land Surveys, and (5) City Engineer.

Facility Inspection - An inspection report covering the facility in terms of equipment, containment, operation, drainage, security, etc. may provide essential information necessary to formulate the SPCC Plan. Therefore, such reports would best serve in the more complex facilities and is not considered necessarily an element common to all SPCC Plans.


Several industrial trade associations have developed suggested SPCC Plan preparation guidelines for use by their members. Generally these guidelines were developed for a particular type of facility and have been very helpful. However, care should exercised not to rely totally on any stereotyped format. Each plan is unique to the facility and requires individual thought processes and tailoring to specific spill hazards.

The American Petroleum Institute (API) has prepared a bulletin entitled "Suggested Procedures for Development of Spill Prevention Control and Countermeasures Plans" (API Bulletin D-16). This was designed primarily for oil production facilities.

The National Oil Jobbers Council has prepared a sample SPCC Plan covering a modest sized bulk plant which includes written and graphic details along with a dike design procedure. A copy of this is included in Appendix "B".


An example of a certification page for a SPCC Plan is shown below.


  1. Name of Facility - Washington Bulk Storage Terminal
  2. Type of Facility - Crude Oil Storage and Handling
  3. Date of Initial Operation - 1 January 1974
  4. Location of Facility - 1111 Main Street, Seattle, WA
  5. Name and Address of Owner:
    ABC Oil Company
    PO Box 100
    Oilville, WA 98000
  6. Designated Person Responsible for Oil Spill Prevention:

  7. Oil Spill History - This facility has experienced no significant oil spill event during the twelve months prior 10 January 1974.
  8. Management Approval - Full approval is extended by Management at a level with authority to commit the necessary resources toward spill prevention.

  9. Certification - I hereby certify that I have examined the facility and, being familiar with the provision of 40 CFR, Part 112 attest that this SPCC Plan has been prepared in accordance with good engineering practices.

    Name: B.J. Embo


    (Seal) Registration No. 00000

    Date: 10 January 1974 State: Oregon


Spill Prevention Control and Countermeasure Plan


100 Neverspill Road


PO Box 100


Oilville, Washington 98000


Telephone: (123)456-7890




John Doe, Owner and Manager



Engineer: B.J. Embo


License Number: 0000-00

State: Oregon (SEAL)

Date: 10 January 1974

1. Name and Ownership

Name: ABC Oil Company

100 Neverspill Road

PO Box 100

Oilville, Washington 98000

Telephone: (123)456-7890

Manager: John Doe

505 Oil Road

Oilville, Washington 98000

Telephone: (123)456-0987

Owner: Same

Other Personnel: Secretary - Bookkeeper


Transport Driver

(3) Delivery People

Service Area: King County, Washington


2. Description of Facility

The bulk plant of the ABC Oil Company handles, stores, and distributes petroleum products in the form of motor gasoline, kerosene, and No. 2 fuel oil. The accompanying drawing show the property boundaries and adjacent highway, drainage ditches, onsite buildings, and oil handling facilities.

Fixed Storage: (2) 20,000 gallon vertical tanks (premium gasoline)

(2) 20,000 gallon vertical tanks (regular gasoline)

(2) 20,000 gallon vertical tanks (No. 2 fuel oil)

(1) 20,000 gallon vertical tank (kerosene)

Total: 140,000 gallons

Vehicles: (1) Transport Truck

(4) Tank wagon Delivery Trucks


The bulk plant is surrounded by steel security fencing and the gate is locked closed when the plant is unattended. Two area lights are located in such positions so as to illuminate the office and storage areas.

3. Past Spill Experience


4. Spill Prevention - Storage Tanks

1. Each tank is UL-142 construction (aboveground use)

2. The main outlet valve on each tank is locked-shut when the plant is unattended.

3. Each tank is equipped with a direct-reading gauge.

4. Venting capacity is suitable for the fill and withdrawal rates.

5. Main power switch for pumps is located in a box which is locked when the bulk plant is unattended.

6. A dike surrounds the tank assembly. Its volume (height vs. area) is computed based on the single largest tank within (20,000 gallons) and allowance is made for additional vertical tank displacement volumes below the dike height (estimated spill liquid level). Total storage capacity is 140,000 gallons. A 2-inch water drain is located at the lowest point within the dike enclosure and it connects to a normally-closed gate valve outside the dike.


5. Spill Prevention - Vehicular

1. Onsite

The frontal highway ditch and the ditch on the property's southern boundary intersect before crossing the highway through a culvert headed eastward and eventually to a stream located approximately one-half mile distant. Emergency containment action will constitute the erection of an earthen dam and placement of absorbent pillars at the entrance of the culvert. Additional cascading of barriers will be provided as necessary.

Personnel training and drill are described herein later.

2. Offside

Each vehicle is equipped with a shovel and two absorbent pillars. The driver is instructed to achieve emergency containment, if possible, then call the office for help immediately.


6. Personnel

All personnel have been instructed and rehearsed in the following spill prevention and countermeasure plans:

1. No tanks or compartments to be filled without prior checking reserves.

2. No pump operations unless attended continuously.

3. Warning signs are displayed to check for line disconnections before vehicle departures.

4. Instruction has been held on oil spill prevention, containment, and retrieval methods, and a "dry-run" drill for an on-site vehicular spill incident has been conducted.

5. Instructions and phone numbers have been publicized and posted at the office regarding the report of a spill to the EPA and the Washington State Department of Ecology.

6. Instructions and company regulations have been posted conspicuously which state to oil spill prevention and countermeasure procedures.


7. Future Spill Prevention Plans

By 10 January 1975 (implementation deadline) the following additional plans will be completed:

1. On-site storage of spill containment and retrieval materials and equipment: bagged absorbent, absorbent pillars and booms, and tools. Storage facility will be well-publicized and clearly defined.

2. Installation of a sand-filled catchment basin for minor, routine spillage at loading pump intakes and at loading rack. Sand to be periodically replaced.

3. A routine inspection program with check-off listing of tanks, piping, valves, hoses, and pumps for the prevention of both major spills and also minor spills or leakage through proper maintenance.

John Doe




1. General Code for Normally Stable, Flammable or Combustible Liquids.

a) The volumetric capacity of the diked area shall not be less than the greatest amount of liquid that can be released from the largest tank within the diked area, assuming a full tank, plus a freeboard of at least twelve inches. The capacity of the diked area enclosing more than one tank shall be calculated by deducing the volume of the tanks other than the largest tank below the height of the dike.

b) Walls of the diked area shall be of earth, steel, concrete, or solid masonry designed to be liquid-tight and to withstand a full hydrostatic head. Earthen walls 3 feet or more in height shall have a flat section at the top not less than 2 feet wide. The slope of an earthen wall shall be consistent with the angle of repose of the material of which the wall is constructed.

c) The walls of the diked area shall be restricted to an average height of 6 feet above the interior grade.

d) Where provision is made for draining water from diked areas, drainage shall be provided at a uniform slope of not less than 1 percent away from tanks toward a sump, drain box, or other safe means of disposal located at the greatest practical distance from the tank. Such drains shall normally be controlled in a manner so as to prevent flammable or combustible liquids from entering natural water courses, public sewers, or public drains. Control of drainage shall be accessible under fire conditions.

e) No loose combustible material, empty or full drum of barrel, shall be permitted within the diked area.

f) Each diked area containing two or more tanks shall be subdivided preferably by drainage channels or at least by intermediate curbs in order to prevent spills from endangering adjacent tanks within the diked area as follows:

1) When storing normally stable, flammable or combustible liquids, one subdivision for each tank in excess of 100,000 gallons and one subdivision for each group of tanks (no tank exceeding 100,000 gallons capacity) having an aggregate capacity not exceeding 150,000 gallons.

Figure 1 -- Example of Design: Vertical Tanks Only

Plan View - Available Dike Position


(a) Minimum Containment Volume is single largest tank within dike: 8500 gallons.

This example: 8500 gallons X .1337 cu. ft./gal. - 1136 cu. ft.

(b) Available Dike Area

This example: 50 ft. X 30 ft. = 1500 sq. ft.

(c) Available Dike Height "h" is:

This example: h X Area of Dike = Min. Containment Volume + h X 3.14 X radius squared of each tank (except largest tank)

h X 1500 sq. ft.. = 1136 cu. ft. + h X 3.14 X ((2)squared) + (2)squared)

1500h - 25.12h = 1474.88 cu. ft.

1474.88h = 1136 cu. ft.

h = 1136/1474.88 = .77 ft. + freeboard (10% industry standard) = .84 ft.

h = 10.08 inches

Figure 2 -- Example of Design: Horizontal Tanks Only

Plan View - Available Dike Position


(a) Minimum Containment Volume is single largest tank within dike: 15,000 gallons

This example: 15,000 gallons X .1337 cu. ft./gal. = 2006 cu. ft.

(b) Available Dike Area

This example: 30 ft. X 45 ft. = 1350 sq. ft.

(c) Available Dike Height "h" is:

This example: h X Area of Dike = Min. Containment Volume

h X 1350 sq. ft. = 2006 cu. ft.

h = 2006/1350

h = 1.486 ft. + freeboard (10% industry standard) = 1.635 ft. = 19.62 inches

Figure 3 -- Example of Design: Horizontal and Vertical Tanks

Plan View - Available Dike Position


(a) From code, the Minimum Containment Volume is single largest tank within dike: 20,000 gallons

This example: 20,000 gallons X .1337 cu. ft./gal. = 2674 cu. ft.

(b) Available Dike Area

This example: 30 ft. X 75 ft. = 2250 sq. ft.

(c) Observe that some volume of the vertical tanks goes below the dike wall height (see last sentence, paragraph 1(a)). This volume of the second 20,000 gallon tank (and any additional verticals) assumed not ruptured must be considered.

Average Dike Height "h" is:

This example: h X Area of Dike = Min. Containment Volume + h X circular area of second (and any additional vertical tanks.)

h X 2250 sq. ft. = 2674 cu. ft. + h X 3.14 X ((5.25)Squared)(radius squared)

2250h-86.5h = 2674

2163.5h = 2674

h = 2674/2163.5 = 1.236 ft. + freeboard (10% industry standard)

h = 1.3596 ft. = 16.32 inches



Discharge: Includes, but is not limited to, any spilling, leaking, pumping, pouring, emitting, emptying, or dumping. Excludes discharges in compliance with a permit under section 402 of the CWA; discharges resulting from circumstances identified, reviewed, and made part of the public record with respect to a permit issued or modified under section 402 of the CWA, and subject to a conditions in such permit; or continuous or anticipated intermittent discharges from a point source, identified in a permit or permit application under section 402 of the CWA, that are caused by events occurring within the scope of relevant operating or treatment systems.

Facility: Any mobile or fixed, onshore or offshore building, structure, installation, equipment, pipe, or pipeline use in oil well drilling operations, oil production, oil refining, oil storage, and waste treatment. The boundaries of a facility may depend on several site-specific factors, including, but not limited to, the ownership or operation of buildings, structures, and equipment on the same site and the types of activity at the site.

Great Lakes: Lakes Superior, Michigan, Huron, Eric, And Ontario, their connecting and tributary waters, the Saint Lawrence River as far as Saint Regis, and adjacent port areas.

Harmful Quantity: Includes discharges of oil that violate applicable water quality standards or cause a sludge or emission to be deposited beneath the surface of the water or upon adjoining shorelines.

Higher Volume Areas: Includes the ports of: Boston, MA; New York, NY; Port Delaware Bay And River to Philadelphia, PA; St. Croix, VI; Pascagoula, MS; Mississippi River from Southwest Pass, LA to Baton Rouge, LA; Louisiana Offshore Oil Port (LOOP), LA; Lake Charles, LA; Sabine-Neches River, TX; Galveston Bay and Houston Ship Channel, TX; Corpus Christi, TX; Los Angeles/Long Beach Harbor, CA; San Francisco Bay, San Pablo Bay, Carquinez Strait, and Suisun Bay to Antioch, CA; Saints of Juan De Fuca and Puget Sound, WA; and Prince William Sound, AK.

Injury: A measurable adverse change, either long- or short-term, in the chemical or physical quality or the viability of a natural resulting either directly or indirectly from exposure to a discharge of oil, or exposure to a product of reactions resulting from a discharge of oil

Inland Area: The area shoreward of the boundary lines defined in 46 CFR part 7, except in the Gulf of Mexico, and excluding the Great Lakes. In the Gulf of Mexico, the Inland Area is the area shoreward of the lines of demarcation (COLREG lines) defined in 33 CFR 80.740-80.850.

Navigable Waters: As defined by 40 CFR 110.1, means the waters of the United States, including the territorial seas. The term includes:

(a) All waters that are currently used, were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters that are subject to the ebb and flow of the tide;
(b) Interstate waters, including interstate wetlands;
(c) All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sand flats, and wetlands, the use, degradation, or destruction of which would affect or could affect interstate or foreign commerce including any such waters:

(1) That are or could be used by interstate or foreign travelers for recreational or other purposes;
(2) From which fish or shellfish are or could be taken and sold in interstate or foreign commerce;
(3) That are used or could be used for industrial purposes by industries in interstate commerce;

(d) All impounds of waters otherwise defined as navigable waters under this section;
(e) Tributaries of waters identified in paragraphs (a) through (d) of this definition, including adjacent wetlands; and
(f) Wetlands adjacent to waters identified in paragraphs (a) through (e) of this definition; Provided, that waste treatment paragraph(s) are not waters of the United States.

Near shore Area: The area extending seaward 12 miles from the boundary lines defined in 46 CFR part 7, except in the Gulf of Mexico. In the Gulf of Mexico, the near shore area is the area extending seaward 12 miles from the line of demarcation (COLREG lines) defined in 33 CFR 80.740-80.850.

Non-persistent Oil: A petroleum-based oil that, at the time of shipment, consists of hydrocarbon fractions; (1) at least 50% of which by volume, distill at a temperature of 340 degrees C (645 degrees F) and (2) at least 95% of which by volume, distill at a temperature of 370 degrees C (700 degrees F). A Group 1 oil can also be a non-petroleum oil with a specific gravity less than 0.8.

Non-petroleum Oil: Oil of any kind that is not petroleum-based. It includes, but is not limited to, animal and vegetable oils.

Oil: Oil in any kind or in any form, including, but not limited to petroleum, fuel oil, sludge, oil refuse, and oil mixed with wastes other than dredged soil.

Onshore Production Facilities: Includes all wells, flow lines, separation equipment, storage facilities, gathering lines, and auxiliary non-transportation-related equipment and facilities in a single geographical oil or gas field operated by a single operator.

Owner/Operator: Any person owning or operating an onshore facility or an offshore facility, and in the case of any abandoned offshore facility, the person who owned or operated or maintained such facility immediately prior to such abandonment.

Persistent Oil: Includes a petroleum-based oil that does not meet the distillation criteria for a non-persistent oil. Persistent oils are further classified based on specific gravity as follows: Group II -- specific gravity less than 0.85, Group III -- specific gravity between 0.85 and less than 0.95, Group IV -- specific gravity 0.95 or greater. Persistent oils also include non-persistent oils with a specific gravity of 0.8 or greater. These oil are further classified based on specific gravity as follows: Group II -- specific gravity between 0.8 and less than 0.85, Group III -- specific gravity between 0.85 and less than 0.95 and Group IV -- specific gravity of 0.95 or greater.

Regional Administrator: The EPA Regional Administrator or a designee of the Regional Administrator, in and for the Region in which the facility is located.

Rivers and Canals: Includes bodies of water confined within the inland area with a project depth of 12 feet or less, including the Intracoastal Waterway and other waterways artificially created for navigation.

SPCC Plan: The document required by the Oil Pollution Prevention regulation that details the equipment, manpower, procedures, and steps to prevent, control and provide adequate countermeasures to an oil spill. The plan is a written description of the facility's compliance with the procedures of this regulation.

Worst-Case Discharge: In the case of a vessel, a discharge in adverse weather conditions of its entire cargo; and in the case of an onshore or offshore facility, the largest foreseeable discharge in adverse weather conditions.

Last Modified on Jun 14, 2023
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