UNITED STATES DEPARTMENT OF AGRICULTURE

Rural Development Utilities Programs

BULLETIN 1724E-302 

RD-GD-2008-55

SUBJECT: Design Guide for Oil Spill Prevention and Control at Substations

TO: All Electric Borrowers

EFFECTIVE DATE: Date of Approval 

OFFICE OF PRIMARY INTEREST: Transmission Branch, Electric Staff Division

FILING INSTRUCTIONS: This bulletin replaces Bulletin 1724E-302, Design Guide for Oil 

Spill Prevention and Control at Substations, issued in April 1993. 

AVAILABILITY: This bulletin can be accessed via Internet at:

http://www.usda.gov/rus/electric/bulletins.htm

PURPOSE: This bulletin provides guidance and assistance in protecting the environment 

against accidental oil spills. This publication aids the electric borrower in interpreting Federal

regulations and developing the necessary documents and oil retention systems to meet these 

regulations. 

January 14, 2008

Assistant Administrator Date

Electric Program

Disclaimer: The contents of this guidance document does not have the force and effect of law and is not 

meant to bind the public in any way. This document is intended only to provide clarity to the public 

regarding existing requirements under the law or agency policies. 
Bulletin 1724E-302 

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TABLE OF CONTENTS

CHAPTER 1: INTRODUCTION

1.1 SCOPE OF BULLETIN........................................................................................................ 9

1.2 PURPOSE OF BULLETIN .................................................................................................. 9

1.3 EPA REGULATIONS.......................................................................................................... 9

1.4 SCOPE OF AN SPCC PLAN ............................................................................................. 10

1.5 NEED FOR AN EFFECTIVE SPCC PLAN ...................................................................... 10

CHAPTER 2: GENERAL INFORMATION CONCERNING SPCC PLANS

2.1 FACILITIES AFFECTED BY EPA REGULATIONS ...................................................... 11

2.2 PERSONS RESPONSIBLE FOR SPCC PLANS............................................................... 13

2.3 NAVIGABLE WATERS.................................................................................................... 13

2.4 COMPLETION OF SPCC PLAN....................................................................................... 14

2.5 CERTIFICATION OF SPCC PLAN .................................................................................. 14

2.6 SAFEKEEPING OF SPCC PLAN ..................................................................................... 14

2.7 AMENDMENTS TO THE SPCC PLAN............................................................................ 14

CHAPTER 3: ELECTRICAL FACILITY APPLICABILITY

3.1 REGULATIONS................................................................................................................. 17

3.2 FACTORS INFLUENCING THE EXTENT OF DAMAGE OF ANOIL SPILL............. 17

3.3 OIL CAPACITIES OF EQUIPMENT................................................................................ 18

CHAPTER 4: GUIDELINES FOR PREPARATION AND IMPLEMENTATION OF AN SPCC 

PLAN

4.1 GENERAL.......................................................................................................................... 21

4.2 MAJOR SECTIONS OF AN SPCC PLAN........................................................................ 21

4.3 CONTENTS OF AN SPCC PLAN..................................................................................... 21

4.4 SUBSTITUTION OF AN SPCC SPILL CONTINGENCY PLAN FOR REQUIRED 

PREVENTION MEASURES............................................................................................. 22

4.5 USING SOFTWARE TO MODEL SPILLS.........................................................................23

CHAPTER 5: CHEMICAL AND PHYSICAL PROPERTIES OF OIL

5.1 PROPERTIES OF OIL ....................................................................................................... 25

5.2 CHEMICAL CHANGES MADE BY OIL......................................................................... 25

5.3 BIOLOGICAL CHANGES TO OIL .................................................................................. 25

5.4 NATURAL AND ENVIRONMENTAL CONDITIONS INFLUENCING THE 

DAMAGE5FROM OIL SPILLS........................................................................................ 25

5.5 THE BEHAVIOR OF OIL WHEN USING BOOMS ........................................................ 30

CHAPTER 6: OIL SPILL PREVENTION TECHNIQUES

6.1 OIL RETENTION SYSTEMS............................................................................................ 33

6.2 YARD SURFACING AND UNDERLYING SOIL........................................................... 33

6.3 PIT LINERS AND SEALERS............................................................................................ 34

6.4 SUBSTATION DITCHING ............................................................................................... 35

6.5 COLLECTING POND WITH TRAP................................................................................. 36
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6.6 POLYMER AGENTS......................................................................................................... 39

6.7 OIL SEPARATOR TANK ................................................................................................. 43

6.8 OIL STOP VALVE............................................................................................................. 44

6.9 GRAVEL-FILLED EQUIPMENT PITS............................................................................ 45

6.10 OIL CONTAINMENT PITS ............................................................................................. 50

6.11 SUMP PUMPS................................................................................................................... 52

6.12 GATE VALVES ................................................................................................................ 54

CHAPTER 7: OIL CONTAINMENT IN NAVIGABLE WATERS

7.1 GENERAL.......................................................................................................................... 55

7.2 BOOMS .............................................................................................................................. 55

7.3 CONTAINMENT DAMS................................................................................................... 69

7.4 COLLECTING AGENTS................................................................................................... 72

CHAPTER 8: OIL REMOVAL MATERIALS

8.1 SORBENTS ........................................................................................................................ 73

8.2 MINERAL PRODUCTS .................................................................................................... 73

8.3 WHEN AND HOW TO USE SORBENTS........................................................................ 76

8.4 BIOLOGICAL DEGRADATION...................................................................................... 81

8.5 COMBUSTION.................................................................................................................. 82

8.6 SINKING AGENTS ........................................................................................................... 83

CHAPTER 9: OIL REMOVAL ON WATER

9.1 OIL REMOVAL METHODS............................................................................................. 85

9.2 VACUUM UNITS.............................................................................................................. 85

9.3 SKIMMERS........................................................................................................................ 86

CHAPTER 10: OIL SPILLS ON LAND

10.1 MIGRATION OF PETROLEUM PRODUCTS IN SOIL AND GROUNDWATER...... 91

10.2 ROCKS AND SOIL.......................................................................................................... 91

10.3 GROUNDWATER ........................................................................................................... 92

10.4 BEHAVIOR OF SPILLED OIL IN SOIL........................................................................ 94

10.5 LAND SPILL CONTROL AND RECOVERY................................................................ 98

10.6 GROUNDWATER REMOVAL ...................................................................................... 99

10.7 GROUNDWATER ABSORPTION ............................................................................... 108

10.8 SOIL WASHING............................................................................................................ 108

CHAPTER 11: OIL DISPOSAL

11.1 RECLAMATION ........................................................................................................... 109

11.2 BURNING ...................................................................................................................... 109

11.3 INCINERATION............................................................................................................ 110

11.4 GENERATING STATION DISPOSAL. ....................................................................... 110

11.5 BURIAL.......................................................................................................................... 110

11.6 LAND SPREADING (LAND FARMING).................................................................... 111
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TABLE OF FIGURES

Figure 5-1: Some Properties of Petroleum Products That Affect Spill Behavior......................... 26

Figure 5-2: A Hypothetical Floating Barrel of Oil ....................................................................... 27

Figure 5-3: Oil Spreading... ......................................................................................................... 28

Figure 5-4: Development of an Oil Slick...................................................................................... 29

Figure 5-5: Typical Spill Distribution Patterns............................................................................. 29

Figure 5-6: Entrainment Failure.................................................................................................... 31

Figure 6-1: Methods of Ditch Construction................................................................................. 35

Figure 6-2: Typical Oil Drainage System for 345/138 kV Outdoor Substation..........................36

Figure 6-3: Cross Section of Oil Drainage System.......................................................................37

Figure 6-4: Oil Trap or Skimming Unit...................................................................................... 37

Figure 6-5: Oil Trap in Containment Pit..................................................................................... 38

Figure 6-6: Oil Trap Construction Using Galvanized or PVC Pipe............................................ 39

Figure 6-7: Imbiber Beads® Gravity-Flow Drain Protection System-Operational Process....... 40

Figure 6-8: Example of an Imbiber Beads® Gravity Drain Protection System .......................... 41

Figure 6-9: Imbiber Beads® Gravity-Flow Drain Protection System–Curb Application ........... 41

Figure 6-10: Typical Construction of Oil Separator Tank............................................................ 43

Figure 6-11: Transformer–Accumulating Tank Combination...................................................... 44

Figure 6-12: Oil Stop Valve Installation....................................................................................... 45

Figure 6-13: Plan View of Equipment Pit..................................................................................... 47

Figure 6-14: Details of Equipment Pit.......................................................................................... 48

Figure 6-15: Typical Drain Pit...................................................................................................... 49

Figure 6-16: Oil Containment Pit ................................................................................................. 50

Figure 6-17: Transformer Dike..................................................................................................... 51

Figure 6-18: Dike, Sponge Area, and Stile Details....................................................................... 52

Figure 6-19: Above Grade Sump Pump Discharge....................................................................... 53

Figure 6-20: Schematic Diagram of Sump Pump Control Using Equipment Oil Limit Switch or

Oil Sensing Probe .................................................................................................... 53

Figure 6-21: Motor-Operated Gate Valve..................................................................................... 54

Figure 7-1: Components of a Boom............................................................................................. 56

Figure 7-2: Boom Tension Members........................................................................................... 58

Figure 7-3: Boom Couplings........................................................................................................ 59

Figure 7-4: Boom “Planing” in Current....................................................................................... 60

Figure 7-5: Wind Effect on Oil Movement.................................................................................. 62

Figure 7-6: Action of Spilled Oil in Fast Current Rivers............................................................. 63

Figure 7-7: Flexible vs Rigid Skirts............................................................................................. 64

Figure 7-8: Anchoring a Boom in Deep Water............................................................................ 65

Figure 7-9: Suggested Boom-to-Shoreline Angles for Different Current Velocities .................. 66

Figure 7-10: Possible Problems Caused by Improper Boom Anchoring...................................... 67

Figure 7-11: Moving Deployment ................................................................................................ 68

Figure 7-12: Changing Currents ................................................................................................... 69

Figure 7-13: Earthen Dam, Cross Section .................................................................................... 70

Figure 7-14: Earthen Dam, Cross Section .................................................................................... 70

Figure 7-15: Cross Section of a Sorbent Fence ............................................................................ 71
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Figure 8-1: Straw Skimmer........................................................................................................... 79

Figure 8-2: Straw Skimming Installation...................................................................................... 79

Figure 9-1: Tank Truck................................................................................................................. 86

Figure 9-2: Three Types of Enlarged Suction Heads (A) Duckbill, (B) Pipe Extension, (C) 

Flexible ....................................................................................................................... 87

Figure 9-3: Weir Skimmer Operation ........................................................................................... 88

Figure 10-1: Hypothetical Groundwater System.......................................................................... 93

Figure 10-2: Generalized Shapes of Spreading Cones at Immobile Saturation............................ 95

Figure 10-3: Demonstration of Possible Migration to Outcrop, Followed by Second Cycle of 

Groundwater Contamination.................................................................................... 96

Figure 10-4: Movement to Groundwater...................................................................................... 97

Figure 10-5: Contaminating Effect on Soil Caused by Vertical Movement of Oil on Fluctuating 

Water Table.............................................................................................................. 98

Figure 10-6: Fluid Oil Floating on Water Table and Showing Elongation of “Pancake” in 

Direction of Water Movement............................................................................... 100

Figure 10-7: Oil on Water Table is Trapped in Cone of Depression Created by Drawdown of 

Pumping Well ........................................................................................................ 100

Figure 10-8: Oil Moving with Shallow Groundwater Intercepted by Ditch Constructed Across 

Migration Path ....................................................................................................... 101

Figure 10-9: System for Skimming Water Surface in Ditches or Wells..................................... 102

Figure 10-10: Typical Conditions During Latter Stage of Migration of Oil to Water Table...... 103

Figure 10-11: Effect on Water Table of Pumping from Well C................................................. 104

Figure 10-12: Diagrammatic Illustration of Development of a Cone of Depression Based on an 

Actual Aquifer Test.............................................................................................. 105

Figure 10-13: Selected Drawdown Data for an Aquifer Test ..................................................... 105

Figure 10-14: Drawdown Configuration of Well Pumping from Inclined Water ...................... 106

Figure 10-15: Well Pumping Using Two Pumps........................................................................ 107
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TABLE OF APPENDICES

Appendix A—EPA Regional Offices

Appendix B—Normal Precipitation Tables

Appendix C—SPCC Typical Example

Appendix D—Optional SPCC Wall Plan

Appendix E—Contributors

ABBREVIATIONS

Agency — Refers to “Rural Development Utilities Programs” 

CFR—Code of Federal Regulations

EPA—Environmental Protection Agency FOA—

Forced oil and air (Transformer) IEEE—Institute of 

Electrical and Electronic Engineers OA—Oil and air 

(Transformer)

OCB—Oil circuit breaker 

PE—Professional engineer 

PVC—Polyvinylchloride

RD—Rural Development Utilities Programs

SPCC—Spill Prevention Control and Countermeasure Plan 

ppm—Parts per million

CI—Also known as “Cheap Insurance” 

HDPE—High density polyethylene 

HFB—Hydrocarbon flow barriers 

NAPL—Nonaqueous phase liquid EPRI—

Electrical Power Research Institute

MOSES-MP—Mineral Oil Spill Evaluation System- Multi-Phase 

MP—Multi-Phase

PCB—Polychlorinated biphenyl
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CHAPTER 1 

INTRODUCTION

1.1 SCOPE OF BULLETIN

This bulletin covers oil spill prevention and control as a result of accidental discharges of oil 

from power facilities and electrical equipment containing oil. Topics include (1) applicability of 

Oil Pollution Prevention Regulations (40 CFR, Part 112) published by the Environmental 

Protection Agency (EPA) regarding electrical facilities and equipment; (2) preparation and 

implementation of an oil spill prevention, control, and countermeasure (SPCC) plan for those 

facilities that, because of their proximity to navigable waters and amount of oil contained, are 

required by EPA regulations to have an operational SPCC plan; (3) properties of oil commonly 

used or stored in electrical facilities and equipment; (4) techniques, procedures, and methods for 

oil spill prevention, its containment, removal, and disposal; and (5) an example of a typical 

SPCC plan.

1.2 PURPOSE OF BULLETIN

This bulletin is intended only as a guide to enable electric program borrowers to meet the 

requirements of the EPA regulations. Each borrower, however, is responsible for assuring 

compliance with the regulations.

1.3 EPA REGULATIONS

The original Spill Prevention, Control, and Countermeasure (SPCC) rules were published on 

Dec. 11, 1973 (38 Fed. Reg. 34164). Revisions to the SPCC program were initially proposed on 

Oct. 22, 1991 (56 Fed. Reg. 54612). Subsequent proposals to amend the SPCC regulations were 

made in 1993, 1997, and 1999. Final SPCC Phase I amendments were published on July 17, 

2002 (67 Fed. Reg. 47042). The final Phase I amendments became effective on Aug. 17, 2002, 

and can be considered the foundation for the current SPCC program and this guide. Additional 

final amendments to the Phase I regulations were published on Dec. 26, 2006 (Fed. Reg. 77357) 

to address issues applicable to “small facilities” and “oil-filled equipment.” EPA issued the 

“SPCC Guidance for Regional Inspectors” to help explain how the Phase I amendments should 

be implemented. The latest regulations and guidance can be found on EPA’s web page at 

www.epa.gov/oilspill. All current EPA SPCC regulations and guidelines should be consulted 

before SPCC implementation.

To comply with the regulations, a company should conduct an engineering assessment of each 

power facility to determine the potential for oil discharge and the resulting impact.. This 

assessment is to be based on considerations of the volume of oil and the location of the facility 

relative to waters that may be affected. If a potential exists, the regulations require the 

preparation and implementation of an SPCC plan for all new and old facilities that could 

reasonably be expected to discharge oil into the navigable waters and groundwater of the United 

States or adjoining shorelines.
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1.4 SCOPE OF AN SPCC PLAN

The SPCC plan should address both oil spill prevention and the measures to be employed in the 

event of a spill to control and contain the oil discharge. The plan should include:

• Physical description of facility and a facility diagram showing locations and contents of 

each container. (Containers smaller than 55 gallons do not have to be considered in the 

SPCC plan.)

• Type of oil in each container and its capacity

• Discharge prevention measures

• Discharge or drainage controls

• Spill countermeasures

• Methods of disposal of recovered materials

• Contact list and phone numbers

• Background information to aid reporting—facility address, location, phone numbers, etc.

• Prediction of the direction, rate of flow, and total quantity of oil that could be discharged 

as a result of major equipment failure

• Containment

• Inspections, tests, and records

• Personnel, training programs, and discharge prevention procedures

• Security

1.5 NEED FOR AN EFFECTIVE SPCC PLAN

Besides the necessity of compliance with EPA or state pollution regulations, any sizable oil spill 

from power facilities may carry serious consequences to the utility even though it may not be in 

close proximity to navigable waters. Damage suits, legal fees, penalties, and cleanup expenses 

may arise from oil releases onto neighboring properties and could have a costly impact on the 

utility. Adverse publicity from a spill migrating from the facility’s property could impair the 

utility’s ability to obtain future zoning or other permits, and could detract from the utility’s goals 

of maintaining goodwill with its neighbors and protection of the environment.
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CHAPTER 2

GENERAL INFORMATION CONCERNING SPCC PLANS

2.1 FACILITIES AFFECTED BY EPA REGULATIONS

Before an adequate spill prevention plan is prepared, the engineer first must be thoroughly aware 

of the requirements included in the EPA regulations. This and the next two sections should be 

consulted for an in-depth discussion of the EPA requirements and how they apply to power 

facilities.

Regulation 40 CFR 112, applies to all facilities engaged in drilling, producing, gathering, storing, 

processing, refining, transferring, distributing, using, or consuming oil products. To exclude 

facilities containing and using small quantities of oil, such as those used by homeowners, these 

regulations only apply if the facility meets the following conditions:

a. Facilities with aboveground storage capacities greater than 1,320 gallons in aggregate 

storage. Containers of less than 55 gallons are excluded, or

b. Facilities with a total storage capacity greater than 42,000 gallons of buried oil storage 

unless the facility is exempted because it is subject to all of the technical requirements 

of 40 CFR 280 or 281, or

c. Facilities that, because of their location, could reasonably be expected to discharge oil 

into or on the navigable waters of the United States or its adjoining shorelines, or

d. Locations required by the EPA Regional Administrator to have an entire SPCC plan, or 

applicable part, completed so that the purpose of the Clean Water Act is met.

2.1.1 Qualified Facilities - EPA created a subcategory of facilities known as “qualified 

facilities” that have the option of following certain streamlined regulations designed to 

reduce the burdens associated with the SPCC program. A qualified facility must not have 

had 1) a single discharge of oil to navigable waters exceeding 1,000 U.S. gallons or 2) two 

discharges of oil to navigable waters, each exceeding 42 U.S. gallons within any twelvemonth period, in the three years prior to the SPCC plan certification date, or since 

becoming subject to 40 CFR part 112 if operating for less than three years. See 40 CFR 

Part 112.6 and 112.7

2.1.2 Small Qualified Facilities - If a facility has 10,000 gallons or less in aggregate above 

ground oil storage capacity and has an oil discharge history allowing it to be classified as a 

qualified facility, then an owner/operator of the facility:

• May prepare a self-certified SPCC Plan instead of one reviewed and certified by a 

Professional Engineer (PE)

• May meet tailored facility security and tank integrity inspection requirements 

without PE certification
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• May prepare a plan which includes PE certified environmentally equivalent 

measures or impracticability determinations that would require PE certification for 

only the portions dealing with environmental equivalence and impracticability 

determinations. The remaining portions of the plan could be self-certified by the 

facility owner/operator.

2.1.3 Contingency Plan in Lieu of Secondary Containment for Qualified Oil-filled 

Operational Equipment - If a piece of equipment meets the definition of Oil-filled 

operational equipment at 40 CFR part 112.2 (e.g. transformers, capacitors and electrical 

switches) and has the oil discharge history required of a qualified facility, instead of 

providing secondary containment for that piece of equipment, the owner/operator may 

choose to prepare an oil spill contingency plan as described a 40 CFR Part 109. In 

addition, the owner/operator must prepare an inspection or monitoring program for 

detecting failure/release and a written commitment of manpower, equipment and 

materials to quickly control and remove discharged oil. Under this option it is not 

necessary for a PE to provide a written determination that containment is impracticable 

for this piece of equipment. (40 CFR Part 112.7(k)) Note: EPA has determined that 

generator sets may not be considered “oil-filled electrical equipment”. (71 Fed. Reg. No. 

247, p. 77276).

Before the engineer decides to provide a 40 CFR Part 109 plan to avoid the requirement 

for secondary containment, the engineer should consider the burdens of maintaining an 

up-to-date Part 109 spill response plan and compare that approach to a decision to accept 

the general secondary containment requirement and use “active containment” measures, 

when appropriate, to satisfy those requirements. See Section 3.2, below.

The Agency recommendations are:

a. Use of an oil spill contingency plan in lieu of oil retention systems: If the borrower’s 

engineer reviewing the facility determines that there is no likelihood of oil reaching 

navigable waters, it is responsibility of the borrower’s engineer to adequately show 

this in the SPCC plan and to include a step-by-step discussion of the cleanup 

procedures that will be used in the event of a spill. The borrower should be aware that 

possible serious consequences are associated with developing an SPCC plan around 

cleanup rather than prevention.

b. Plans that employ general secondary containment should be prepared for:

• Any facility that has the possibility of discharging oil into the groundwater

• Any facility located in urban, suburban, or rural areas where adverse publicity could 

be detrimental in obtaining future zoning, building permits, etc.

c. If pits, tanks, or ponds are used, they should be sized to hold at least 100 percent of the 

oil contained in the largest single piece of equipment plus a reasonable allowance for 

precipitation, and not be based on the total capacity of the facility. Berms and
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equipment pits should be provided with a means to drain rainwater from the enclosures 

without possible loss of oil. This may be done by using polymer agents, manual 

valves, or any other acceptable means.

d. The borrower’s engineer should then identify the significant potential spillage areas 

and, based on prudent engineering judgment, eliminate small or insignificant sources 

of potential spills. This engineering judgment should carefully weigh the probability of 

the equipment spill occurrence and the magnitude of the probable spill size. This may 

result in the decision to employ secondary containment plans rather than spill 

contingency plans for such devices as current transformers, coupling capacitor 

potential devices, potential transformers, small station service transformers, and small 

reactors.

2.1.4 Small Qualified Facilities Containing Oil-Filled Equipment - A facility that contains 

“Qualified Oil-filled Operational Equipment” can also be classified as a “Small Qualified 

Facility” , in which case the owner/operator may choose to self-certify the plan and use a 

spill response plan, monitoring and manpower commitment in lieu of secondary 

containment.

2.2 PERSONS RESPONSIBLE FOR SPCC PLANS

Individual SPCC plans should be prepared by the owner/operator of each facility that meets the 

above criteria. An SPCC plan also should be prepared for each mobile or portable oil storage 

facility, and must be applicable for any location to which this unit may be moved.

The owner/operator has the responsibility for preparing a plan covering each facility that could 

“reasonably be expected” to discharge oil into navigable waters or on adjoining shorelines. 

Among the factors that should be considered in making such a determination are:

a. Prior spill history

b. Location (proximity to navigable waters)

c. Potential size of discharge

d. Soil and terrain conditions

e. Frequency and amount of rainfall.

2.3 NAVIGABLE WATERS

The term “navigable waters” is defined to include all of the following:

a. Waters that are navigable, including adjacent territorial seas

b. The entire river system extending upstream to its uppermost tributaries

c. Lakes and ponds used by interstate travelers for recreational or other purposes

d. Intrastate lakes, rivers, and streams from which fish or shellfish are taken and sold in 

interstate commerce

e. Stream beds and riverbeds that normally may be dry and only contain water during 

heavy rain periods.
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f. All wetlands.

This broad interpretation of “navigable waters” basically means that an SPCC plan must be 

prepared and maintained for any facility that may lead to the discharge of oil into any form of 

waters within the United States. This should include groundwater, sole source aquifers used for 

drinking water or other waters designated by your state for protection.

2.4 COMPLETION OF SPCC PLAN

SPCC plans are to be prepared and fully implemented before new facilities become operational. 

This implementation includes any construction or plant modifications, changes in operational 

maintenance or administration, or the training of personnel prescribed in the plan.

2.5 CERTIFICATION OF SPCC PLAN

Unless the plan was prepared and self-certified according to 40 CFR Section 112.6(a), each 

SPCC plan must be (according to EPA) reviewed, certified, and dated by a registered 

professional engineer (PE). The PE must state and attest familiarity with the provisions of 40 

CFR 112, that he or his agent has examined the facility in question, that the plan has been 

prepared in accordance with good engineering practices, that procedures for required inspections 

and testing have been established, and that the plan is adequate for the facility. The 

owner/operator is responsible for final approval and implementation of the plan.

2.6 SAFEKEEPING OF SPCC PLAN

A copy of the SPCC plan must be (according to EPA) maintained at the facility for which the 

plan was prepared if the facility is manned four hours or more per day, or at the nearest field 

office if the facility is not so attended. The plan is to be available for EPA on-site inspection 

during normal working hours. It should be noted that the EPA will not evaluate SPCC plans for 

adequacy and/or completeness, but only as to whether a plan exists. However, if the facility 

experiences spill problems, the plan may be critically reviewed by EPA and by the appropriate 

state and local agencies to determine its adequacy. Based on this review, the EPA may require 

that the plan be amended to include additional preventive measures.

2.7 AMENDMENTS TO THE SPCC PLAN

The owner/operator is required to amend the plan when any of the following events occur:

• When required by the EPA after a review of the plan, submitted because of an oil 

spill

• Whenever there is a change in facility design, construction, operation, or maintenance 

that affects the potential for an oil spill

• Whenever a review by the owner/operator indicates that a more effective control and 

prevention technology will significantly reduce the likelihood of an oil spill

• Each SPCC plan must be reviewed every five years and be recertified by a registered 

professional engineer or by the owner operator if it was self-certified (see Section 2.1.2).
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It is required that documentation of the completion of the review and evaluation be 

performed.

It may be necessary to contact federal or state oil regulatory agencies to confirm 

deadlines for the first and subsequent five-year SPCC plan amendment and the deadlines 

for implementing such amendments.

2.7.1 Plan The owner/operator must (according to EPA) submit the SPCC plan and any 

amendments to the EPA and to the appropriate state agencies for their review whenever a 

facility experiences a single spill of 1,000 U.S. gallons of oil into navigable waters, or a 

discharge of oil in harmful quantities as defined in 40 CFR 110 in any two oil spills 

within a 12-month period.

2.7.2 Information to EPA, State Within 60 days of the occurrence of either of the above 

situations, the owner/operator must submit to the EPA Regional Administrator and to the 

appropriate State agency in charge of oil pollution control the following information:

a. Name of facility

b. Name of the owner/operator of the facility

c. Location of the facility

d. Storage capacity of facility (equipment)

e. Description of the facility, including maps of the site, oil flow path, and topographical 

maps

f. A copy of the SPCC plan with any amendments that address the facility that 

experienced the spill

g. The cause of the spill, including a failure analysis of the system

h. The corrective actions and/or countermeasures taken

i. Additional preventive measures taken or contemplated to minimize the possibility of 

recurrence

j. Other information as the EPA Regional Administrator may require.

2.7.3 EPA Review EPA will review the information and any recommendations made by State 

agencies and may require the operator to amend the SPCC plan. If the EPA proposes any 

amendments to the plan, the operator will be notified either by certified mail or by 

personal delivery specifying the required changes. The amendment required becomes 

effective 30 days after notice, unless the operator appeals. The operator must implement 

the amendment as soon as possible, but no later than six months after the amendment 

becomes part of the plan. Within 30 days of receipt of the notice, the operator may submit 

written information and arguments to appeal any proposed amendment requirements. 

After considering all material presented, the EPA will either notify the operator that an 

amendment is required or rescind the previous notice.

A registered professional engineer must (according to EPA) certify all SPCC plan amendments, 

except those prepared and self-certified according to 40 CFR Section 112.6(a) and those 

proposed by an EPA Regional Administrator.
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The owner/operator of facilities that violate the requirements of the EPA regulations relating to 

the preparation, implementation, or amendment of SPCC plans is subject to a civil penalty for 

each day that such a violation continues. The EPA Regional Administrator may assess or waive 

the civil penalties at his discretion. The penalty will not be assessed until the owner/operator has 

been given notice and an opportunity for a hearing.
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CHAPTER 3

ELECTRICAL FACILITY APPLICABILITY

3.1 REGULATIONS

EPA regulations (40 CFR 112) were originally intended to prevent and control the discharge of 

oil from facilities directly involved with drilling, gathering, refining, storing, and consuming oil 

products for heating, cooling, and manufacturing purposes. EPA has included under the storage 

portions of these regulations electrical apparatuses that contain oil for electrical insulating 

purposes.

Electrical faults in this power equipment can produce arcing and excessive temperatures that 

may vaporize insulating oil, creating excessive pressure that may rupture electrical equipment 

tanks. In addition, operator errors, sabotage, or faulty equipment also may be responsible for oil 

release that may enter waterways.

3.2 FACTORS INFLUENCING THE EXTENT OF DAMAGE OF AN OILSPILL

3.2.1 Factors The initial cause of an oil release or fire in electrical equipment may not always 

be avoidable, but the extent of damage and the consequences for such an incident can be 

minimized or prevented by adequate planning in prevention and control.

The risk of an oil spill caused by an electric equipment failure depends on many factors, 

including:

• Engineering and operating practices (i.e., electrical fault protection, loading practices, 

switching operations, testing, and maintenance)

• Quantities of oil contained within the equipment

• Station layout (i.e., spatial arrangement; proximity to property lines, streams, and 

other bodies of water)

• Station topography and site preparation (i.e., slope, soil conditions, ground cover)

• Rate of flow of discharged oil.

3.2.2 General Secondary Containment Each outdoor facility must be evaluated to select the 

safeguards commensurate with the risk of a potential oil spill. Appropriate containment 

and/or diversionary structures are required to prevent a release to navigable waters. For 

oil-filled electrical equipment, secondary containment must be sufficient to hold the oil 

so that no spill will escape the containment system before it is cleaned up. Examples of 

general secondary containment include

• Dikes, berms, or retaining walls sufficiently impervious to contain oil

• Curbing; culverts, gutters, or other drainage systems

• Oil/water separators

• Weirs, booms, or other barriers

• Spill diversion or retention ponds

• Sorbent material.
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The secondary containment standard for bulk oil storage facilities is more restrictive than general 

secondary containment. Secondary containment for Bulk Oil Storage facilities is called “sized” 

containment and must be capable of containing oil from the largest single container at the facility 

plus sufficient freeboard to contain precipitation. Sized containment generally consists of dikes, 

containment curbs and pits.

3.2.3 Applicability to Electrical Facilities Oil-filled electrical equipment is subject to the 

requirements for “general” secondary containment as described at 40 CFR Part 112.7 which can 

include dikes and berms but can also include “sorbent material”. General secondary containment 

“may be either passive measures or active measures (countermeasures or land-based spill 

response capability) since both are designed to prevent a discharge from reaching navigable 

waters or adjoining shorelines. Passive [secondary containment] measures are permanent 

installations (such as dikes or berms) and do not require deployment or action by the owner or 

operator. However, permanent (passive) containment structures, such as dikes, may not always 

be feasible for certain oil-filled operational equipment (i.e. electrical transformers, capacitors, 

switches.) The owner or operator of an SPCC-regulated facility may instead use the flexibility of 

active containment measures to comply with the general secondary containment requirements for 

oil-filled operational equipment.” (71 Fed. Reg. 247, p. 77279, December 26, 2006).

Since active containment measures are designed to prevent a discharge from reaching navigable 

waters, they are much different that the Part 109 spill contingency plan which is designed to 

respond to a spill after it has reached navigable waters. See Section 2.4, above.

3.2.4 Active Containment Active containment measures are those that require deployment or 

other specific action by the owner or operator. Active containment measures “may be 

deployed either before an activity involving the handling of oil starts, or in reaction to a 

discharge so long as the active measure is designed to prevent an oil spill from reaching 

navigable water or adjoining shore lines. (71 Fed. Reg. 247, p. 77279, December 26, 

2006). Examples of active containment include the use of storm drain covers, spill kits, 

and sorbent materials and the closing of valves. [EPA SPCC Guide for Regional 

Inspectors, 4-16 to 4-20.]

Agency Recommendation: Passive containment measures rather than active measures 

should be used for:

• Any facility that has the possibility of discharging oil into the groundwater

• Any facility located in urban, suburban, or rural areas where adverse publicity could 

be detrimental in obtaining future zoning, building permits, etc.

3.3 OIL CAPACITIES OF EQUIPMENT

In order to determine the size and type of electrical facilities that require an SPCC plan, it is 

necessary to know the oil capacities of each piece of electrical equipment at the facility.
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3.3.1 Preparation Based on the quantities of oil stipulated in the regulations (i.e., 1,320 

gallons aggregate storage of containers 55 gallons or greater), the following electrical 

facilities will probably require the preparation of an SPCC plan:

• Power plants

• Substations

• Switching stations

• Mobile substations

• Large customer installations

• Test facilities

• Pipe-type cables

• Equipment storage and maintenance facilities

3.3.2 Written Plans for Mobile Equipment SPCC plans that cover portable equipment and 

mobile substations should be written so that the plans will be applicable at any and all 

substation or facility locations.
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CHAPTER 4

GUIDELINES FOR PREPARATION AND IMPLEMENTATION OF AN SPCC PLAN

4.1 GENERAL

Detailed guidelines for the preparation and implementation of an SPCC plan are given in 40 CFR

112.7. In general, the plan should be carefully thought out, prepared in accordance with good 

engineering practices, and may follow the plan format presented in Section 112.7, although other 

formats are acceptable. While one may use other formats, such as State plans, integrated 

contingency, and other formats acceptable to the Regional Administrator, the alternate format 

must cross-reference its provision to the requirements listed in the SPCC rule. The alternate 

format must include all applicable SPCC requirements.

The overall objective of this engineering analysis study should be directed toward spill 

prevention by identifying facility weaknesses, and then designing and planning these facilities to 

prevent and/or greatly reduce the occurrence and effects of spills.

4.2 MAJOR SECTIONS OF AN SPCC PLAN

Following a detailed engineering review of the existing proposed facility, an SPCC plan should 

be developed that contains at least the following three major sections:

a. Description of the facility, including topographical maps

b. Identification of sources of potential spills

c. Engineering description of the corrective actions to be taken to prevent a release and, if 

a release occurs, to contain the flow of oil before it reaches navigable waters or 

shorelines.

4.3 CONTENTS OF AN SPCC PLAN

The best method of presentation is that of a narrative engineering report with supporting maps 

and drawings. The description of the facility should be related to the plot plan of the facility, 

including details of drainage patterns and locations of waters that could be affected by oil 

discharges.

After defining the course of potential spills, the predicted maximum quantity and rate of spillage 

should be estimated and, using the topographical maps and available soil data, a prediction 

should be made as to the direction and the rate of flow.

Finally, the engineer must determine whether preventive measures should be provided for each 

source of spillage and, if so, in what form; or adequately show that spill prevention at the facility 

is not practical and discuss the necessary cleanup procedures. The solutions for the preventive 

type SPCC plan may vary widely, depending on the size, type, and general proximity of the 

facility to surface waters and the type of terrain and soil. The solutions may range from dikes, 

culverts, ditches, retention ponds, and curbs to various types of collecting systems.
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4.4 SUBSTITUTION OF AN SPCC SPILL CONTINGENCY PLAN FOR REQUIRED 

PREVENTION MEASURES

Whenever an oil spill contingency plan is substituted for the required prevention measures under 

Section 112.7(d), the owner of the facility must demonstrate in writing and with drawings that 

Part 112 requirements are impractical and/or that there is no likelihood of the oil reaching 

navigable waters. “Impractical,” as interpreted by EPA, means that measures are unsuitable for 

practical use at that facility and not merely uneconomical. In other words, it is not the owner’s 

preference as to which type of plan to develop but, rather, it is totally dependent on whether 

adequate means are available for that particular facility. If it is determined that no prevention 

system is available, the cleanup type plan must discuss detailed cleanup procedures to include 

containment and removal. This latter method will not relieve the owner of the facility from 

liability costs, cleanup costs, and fines as a result of a spill. In fact, these costs may, in many 

cases, amount to many hundreds of times those costs associated with providing a protective 

system initially.

The Agency recommendations are:

a. Use of cleanup procedures in lieu of oil retention systems: If the engineer reviewing 

the facility determines that there is no likelihood of oil reaching navigable waters, it is 

the engineer’s responsibility to adequately show this in the SPCC plan and to include a 

step-by-step discussion of the cleanup procedures that will be used in the event of a 

spill. The borrower should be aware that possible serious consequences are associated 

with developing an SPCC plan around cleanup rather than prevention.

b. Plans that employ general secondary containment should be prepared for:

• Any facility that has the possibility of discharging oil into the groundwater

• Any facility located in urban, suburban, or rural areas where adverse publicity could 

be detrimental in obtaining future zoning, building permits, etc.

c. If pits, tanks, or ponds are used, they should be sized to hold at least 100 percent of the 

oil contained in the largest single piece of equipment plus a reasonable allowance for 

precipitation, and not be based on the total capacity of the facility. Berms and 

equipment pits should be provided with a means to drain rainwater from the enclosures 

without possible loss of oil. This may be done by using polymer agents, manual 

valves, or any other acceptable means.

d. The engineer should then identify the significant potential spillage areas and, based on 

prudent engineering judgment, eliminate small or insignificant sources of potential 

spills. This engineering judgment should carefully weigh the probability of the 

equipment spill occurrence and the magnitude of the probable spill size. This may 

result in the exclusion of such devices as current transformers, coupling capacitor 

potential devices, potential transformers, small station service transformers, and small 

reactors.
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4.5 USING SOFTWARE TO MODEL SPILLS

The Electric Power Research Institute (EPRI) has developed a software program that can be used 

to simulate the outcome of an oil spill within a substation. The Mineral Oil Spill Evaluation 

System—Multi-Phase Code (MOSES-MP) Version 3.0 software for Windows-based PC 

computers provides an easy-to-use method for predicting the likelihood of mineral oil spills from 

substations or other fluids from aboveground storage tanks reaching groundwater or nearby 

surface water. MOSES-MP also predicts the quantity of oil that infiltrates the ground beneath 

electrical equipment and provides soil saturation profiles at user-specified times. The effects of 

frozen days and fire events also can be evaluated. Options allow the user to quickly evaluate 

common mitigation alternatives, such as adding gravel and containment basins. Input data are 

entered using a series of menus. The software then generates graphs showing the volume of spills 

contained on-site, the depth of penetration of on-site spilled oil, the volumes reaching the water 

body surface, the travel time to reach the body of water, and the extent of any oil sheen on the 

water surface. Separate graphs can be produced for spills on dry days only, on wet days only, or 

for all days. A draft SPCC plan also is created that automatically incorporates site characteristics 

and simulation results into an editable text file. The SPCC Plan can be customized to include 

utility-specific information.

The one-dimensional processes of overland flow, based on a kinematic wave approach, consider 

on-site and off-site containments; evaporation; infiltration; surface slope; surface roughness and 

retention in open natural channels and in closed pipes; vegetation cover; thickness of viscous 

boundary layer; and effects of rainfall, frozen conditions, fires, and fire suppression on the flow 

of mineral oil. The two-dimensional processes of oil spreading over surface water bodies include 

those of advection, diffusion, and shoreline retention. The overland flow model uses a Monte 

Carlo approach for selecting input parameter values from user-defined ranges. The values used in 

the simulations for the cases where mineral oil reaches surface water can be saved as output files 

for later review. Input data also can be saved for use in later runs.

The Multi-Phase model uses a finite difference method for solving the Richards equation for 

nonaqueous phase liquid (NAPL) movement. The equations are solved for user-defined input

values. The one-dimensional vertical movement of NAPL in the subsurface considers surface 

ponding, moisture effects, capillary pressure, relative permeability, and the NAPL properties of 

density, viscosity, and air/liquid interfacial tension. The enhanced MP code simulates surface 

spills and the redistribution of oil that has previously infiltrated into soil. The simulations can be 

made by specifying rainfall or a soil moisture profile.
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CHAPTER 5

CHEMICAL AND PHYSICAL PROPERTIES OF OIL

5.1 PROPERTIES OF OIL

Figure 5-1 lists some of the chemical and physical properties of a representative sampling of 

various types of petroleum products that may be found in a power facility and briefly relates how 

these properties affect spill behavior.

5.2 CHEMICAL CHANGES MADE BY OIL

Spilled oil interacts with the environment in several characteristic ways, some of which can be 

predicted from a knowledge of the oil composition and properties.

Spilled oil undergoes chemical changes such as oxidation. Oxidation under the influence of the 

ultraviolet rays of sunlight can eliminate a very thin oil slick. However, oxidation is a mixed 

blessing in that the hydrocarbons contained in oil may oxidize to oxygen-containing compounds 

that are more toxic than the oil.

5.3 BIOLOGICAL CHANGES TO OIL

The biological change process that oil undergoes involves the bacterial decomposition of oil. 

This metabolic decomposition of oil is the single most important natural cleanup operation.

Both chemical and biological processes are active when insulating oil and fuel oil are spilled. 

The importance of each depends on the type of oil and the environmental and temperature 

conditions under which the spill occurs.

5.4 NATURAL AND ENVIRONMENTAL CONDITIONS INFLUENCINGTHE 

DAMAGE FROM OIL SPILLS

In addition to the amount of oil spilled, environmental conditions present at the time of an oil 

spill can greatly influence the amount of damage that results. Calm water, a light breeze, and 

warm temperatures may favor rapid cleanup operations by fast evaporation rates and minimal 

mixing of the oil and the water. On the other hand, rough water conditions hamper cleanup 

operations by the thorough mixing of oil and water, forming an emulsion that impedes oil 

removal and allows oil to penetrate to greater depths.

A variety of natural processes occur when oil is spilled on water, which collectively will result in 

the weathering or aging of the oil. These processes include spreading, evaporation, dissolution, 

emulsification, chemical reaction, and biological degradation. These processes tend to disperse 

the oil and eventually lead to its dissipation or removal from the environment.
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Figure 5-1

Some Properties of Petroleum Products That Affect Spill Behavior
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5.4.1 Spreading Process

By far the most important of these processes is the spreading of the oil to a thin film, for without 

this happening first, many of the other dispersive processes would not occur or would only 

happen at greatly reduced rates. Paradoxically, it is this same tendency to spread rapidly that may 

cause the oil spill to “get away” from cleanup personnel.

Two important driving forces that cause oil to spread on water are gravity and surface tension. 

The fact that oil is lighter—less dense—than water brings the force of gravity into action. Oil is a 

complex mixture of many varying compounds, each of which may have a different density. On 

the average, insulating oil will have an overall density that is about 90 percent of the density of 

water.

To understand the role of gravity in the spreading process, it is useful to consider floating oil 

confined by some type of barrier such as an oil drum constructed from a plastic with a density 

identical to that of oil (Figure 5-2).

This full barrel will have the density of oil that means 90 percent of its volume will be below the 

water’s surface, and 10 percent above. The floating oil extends a height (h) above the surface of 

the water. At any point in the oil surface at the level of the water surface, there is a pressure (p) 

that is attributed to the weight of the oil above the water surface.

Figure 5-2: A Hypothetical Floating Barrel of Oil

Now imagine that the plastic is rapidly disintegrated by the water and the drum is no longer there 

to confine the barrel of oil. The uniform pressure just above the surface of the water becomes an 

unopposed force toward the sides of the (missing) drum, and the oil will spill out over the surface 

of the water, as indicated by Figure 5-3. Since weight is removed as the oil above the surface 

spills away, the oil below the surface floats higher in the water, causing more spillage to the 

sides. Consider also that the height above the water continues to decrease and the sideways force 

from the gravitationally induced pressure decreases with (h). The initial value of (h) and, hence, 

the initial gravitational spilling force depends on the volume of oil spilled. Thus, large spills 

spread more rapidly, and decrease with time.
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Figure 5-3: Oil Spreading

It is important to consider the kinds of forces that oppose spreading forces because spreading 

will cease when the driving and opposing forces are balanced. In the early phase of a large spill, 

the major opposing force is simply the natural tendency of the oil to remain at rest, its inertia. 

However, as the gravitational driving force lessens with the decreasing thickness of the floating 

oil, the opposition from the oil’s viscosity and its drag when sliding becomes important. The 

initial two phases are known as gravity inertial spreading and gravity viscous spreading.

When the slick from oil has thinned to about 0.08 cm (0.03 in.), the gravitational spreading force 

ceases to be a major factor and surface tension effects, which were negligible before, become the 

dominant driving force.

The concept of surface tension can be explained in terms of the forces between the molecules of 

a liquid. A molecule in the interior of a sample of liquid experiences attractive forces from the 

molecules that surround it. A molecule on the surface of the liquid experiences an unbalanced 

force because of attractions with molecules to the sides and below it and the nonexistent or very 

weak interactions that it has with the vapor molecules above the liquid surface. Thus, surface 

molecules experience a net force that pulls them toward the interior. If the amount of surface 

area is somehow increased—a bubble grows, a flat surface curves—something must take place to 

bring molecules from the interior to the surface. The opposition that must be overcome to create 

additional surface is called the surface tension. Wherever there is an interface—such as between 

water and air, oil and air, or oil and water—a surface tension characteristic of the interface will 

exist.

It would be quite advantageous to be able to make accurate predictions about spreading rates 

during this final or surface tension-viscous phase of spreading because all unchecked spills will 

eventually spread by this mechanism. Small spills, which are far more frequent, will spread 

solely because of surface tension. Unfortunately, it is almost impossible to make valid 

predictions for many situations because the spreading coefficient will vary with time.

The evaporation and dissolution of the lighter components of the oil will change as properties 

such as surface tension, density, and viscosity change.

The ambient temperature is important in the surface tension phase of spreading but has only a 

small effect during gravity-forced spreading. For example, at arctic seawater temperatures near
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20° F, the spreading coefficient is approximately zero, and the oil will not spread to a thin film. 

Also, the rate of evaporation and dissolution will increase as the temperature increases.

The evaporation of the lighter oil products, with time, will usually lead to slicks that are 

nonhomogeneous and have thick and thin regions, as shown by Figure 5-4.

Figure 5-4: Development of an Oil Slick

The preceding discussion of the spreading process occurring in calm water is an idealization, 

since wind, waves, and water currents are not considered. Currents and wind will displace the 

entire growing slick from its original location, to include some modification of the shape of the 

slick—Figures 5-5, parts A, B, and C; whereas wave motion coupled with currents will break a 

slick into patches and windrows—parts D and E of Figure 5-5.

Figure 5-5: Typical Spill Distribution Patterns.

A: Quiet Water—Unrestrained Spill. B: Mild Current or Wind. C: Strong Current or 

Wind. D: Light Oil—Moderate Wave Action. E. Swift Current-Wave Action.
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A useful rule of thumb is that the center of a slick will migrate with any current at the speed of 

that current and also will drift in the wind direction at about 3 percent of the wind speed. 

Laboratory measurements indicate that the drift may actually vary from 2.5 percent to 4 percent 

of the wind speed.

5.4.2 Agitation and Disposal of OilSlicks

The agitation of oil slicks because of the breaking waves in rough water and the action of surf 

can be effective in supplying the energy to form the small droplets of stable emulsions and then 

disperse them. Such oil particles—ranging in size from 0.0002 in. to 0.1 in.—have been found in 

the water as far as 150 miles from an original spill.

There also are data indicating that aerosols of oil droplets in air can be formed by the action of 

wind and waves in producing spray.

5.5 THE BEHAVIOR OF OIL WHEN USING BOOMS

When deployed for oil containment in streams or channels, booms will form a ‘U’ shape open to 

the current so that the oil will collect at the bottom of the ‘U.’ The force of the moving current 

tends to confine the oil at the bottom of the ‘U’, placing the deepest part of the floating oil there. 

A vertical cross section would show the oil mass to be wedge-shaped, with its thinner leading 

edge toward the open mouth of the ‘U’ of the boom. The boom needs to float sufficiently high 

above the water to prevent the oil from splashing over the top of it with normal wave action. 

Booms also need to extend deep enough into the water to hold the oil at nominal currents.

It is useful to remember that the average insulating oil will have a density similar to that of ice, 

which is about 90 percent of water’s density. Thus, a pool of oil, like an iceberg, is 90 percent 

below the water surface. If the boom draft below the water surface is one-half foot, the current 

pushing the oil against the bottom of the ‘U’ cannot exceed 1.78 ft./sec.—about 1 knot—without 

the oil running under the bottom of the barrier, a phenomenon called “drawdown.”

Booms require a greater draft to contain oil in currents greater than 1 knot. However, at about

0.75 knots, a phenomenon occurs and a “head-wave” develops on the underside of the leading 

edge of the wedge of oil (Figure 5-6). At currents between 0.75 knots and 1.5 knots, droplets are 

broken off from the turbulent backside of the head-wave. If the slick is long enough, the majority 

of these droplets will rise and rejoin the oil pool. At currents greater than 1.5 knots, the majority 

of the drops escape by running under the barrier, and increasing a boom’s draft will not prevent 

this type of slow leakage. A towed boom experiences essentially the same forces as a stationary 

boom in a current at towing speeds greater than 1.5 knots; droplet drop-off with run-under 

occurs. In fact, if a boom is towed against a current, the sum of current velocity and towing 

velocity cannot exceed 1.5 knots without run-under occurring.
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Figure 5-6: Entrainment Failure
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CHAPTER 6

OIL SPILL PREVENTION TECHNIQUES

6.1 OIL RETENTION SYSTEMS

Once a need for an oil spill prevention system is determined, an engineer must weigh the 

advantages and disadvantages that each oil retention system may have at the facility in question. 

The oil retention system chosen should balance the cost and sophistication of the system to the 

risk of an oil spill reaching navigable waters/environment. The risks will depend on such things 

as soil, terrain, relative closeness to waterways, location with regard to property owners, and 

potential size of the discharge. Each of the systems described below should be considered based 

on their relative merits to the facility under consideration. One system will not always be the best 

choice for all situations and circumstances.

6.2 YARD SURFACING AND UNDERLYING SOIL

Four to six inches of rock gravel surfacing are normally required in all electrical facility yards. 

This design feature benefits the operation and maintenance of the facility by providing proper 

site drainage, reducing step and touch potentials during short circuit faults, eliminating weed 

growth, improving yard working conditions, and enhancing station aesthetics. In addition to 

these advantages, the gravel will aid in fire control and in reducing potential oil spill cleanup 

costs and penalties that may arise from Federal and State environmental laws and regulations.

Yard surfacing should not be considered the only method of secondary oil containment without 

further study dependent on the volume of oil, yard surface area, and slope of substation. It can 

also be considered as a backup in limiting the flow of oil in the event that the oil containment 

system fails.

Soil underlying power facilities usually consists of a nonhomogeneous mass that varies in 

composition, porosity, and physical properties with depth. The soil’s drainage characteristics—

permeability—are of primary concern in the design of an oil containment facility. The 

permeability coefficient, “k”, is a measure of the capacity of the soil to conduct or pass water 

under a unit hydraulic gradient. Coarse grained soils are more pervious and have corresponding 

higher permeability coefficients than fine grained soils. Using the coefficient of permeability, 

“k” and the hydraulic gradient, “i”, the flow volume “V”, discharged through the soil’s crosssectional area, “A”, during time, “t” may be estimated as follows:

V=kiAt

where:

V = volume discharged through the soil, cm3

k = coefficient of permeability, cm/s

i = hydraulic gradient, cm/cm

A = cross sectional area of soil conveying flow, cm2

t = time, seconds
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Soils and their permeability characteristics vary widely as indicated below:

Permeability Coefficient Degree of

(cm/sec) Permeability Type of Soil

-1

Over 10 High Stone, gravel, and coarse- to

medium-grain sand

-1 -3

10 to 10 Medium Medium grain to uniform, fine sand

-3 -5

10 to 10 Low Uniform, fine to silty sand and sandy

clay

6.3 PIT LINERS AND SEALERS

Pits with liners or sealers may be used as part of an oil containment system capable of retaining 

any discharged oil on-site for an extended period of time. Any collection or containment pit -3

should be constructed with materials having medium to high permeability—above 10 cm/sec—

and should be sealed in order to prevent migration of spilled oil into underlying soil layers and 

groundwater. These surfaces may be sealed and/or lined with any of the following materials:

a. Plastic or rubber—Plastic or rubber liners may be purchased in various sizes and 

thickness. Consideration should be given to the selection of a liner that is not subject 

to mechanical injury that may occur as a result of construction, installation, equipment, 

chemical attacks on surrounding media, and oil products.

b. Bentonite (clay)—Clay and bentonite may be used to seal electrical facility yards and 

containment pits. These materials can be placed directly in four- to six-inch layers or

-3

may be mixed with the existing subsoil to obtain a soil permeability of less than 10

cm/sec.

c. Spray-on fiberglass—Spray-on fiberglass is one of the most expensive pit liners 

available, but in some cases the costs may be justifiable in areas that are 

environmentally sensitive. This material offers very good mechanical strength 

properties and provides excellent oil retention.

d. Reinforced concrete—Four to six inches of reinforced concrete also may be used as a 

pit liner. The advantage of this material is that it is readily available at the site at the 

time of initial construction of the facility. The disadvantages of this material are that 

initial preparation is more extensive and materials are not as easily workable as some 

of the other materials.

If materials other than those listed above are used for an oil containment liner, careful 

consideration should be given to not selecting materials—such as asphalt—that may dissolve or 

become soft with prolonged contact with oil.
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The final selection of pit liners or sealers should be based on cost, strength, and durability.

6.4 SUBSTATION DITCHING

One of the simplest methods of providing total substation oil spill control is the construction of a 

ditch entirely around the outside periphery of the station (Figure 6-1). The ditch should be large 

enough to contain all surface runoff from rain and insulating oil. Such ditches may be 

periodically drained by the use of valves. Here again, the method discussed in the previous 

section should be used in determining the allowance for precipitation.

a. Advantages

• Economical

b. Disadvantages

• Periods of heavy rain may not provide adequate containment.

• Standing pools of water may breed insects.

• May not be feasible in porous soil areas.

Figure 6-1: Methods of Ditch Construction
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6.5 COLLECTING POND WITH TRAP

This system consists of a collection pit surrounding the protected equipment, drains connecting 

the collection pits to an open containment pit, an oil trap that is sometimes referred to as a 

skimming unit, and the discharge drain. This system is shown in Figure 6-2.

The collection pit surrounding the equipment is filled with rocks and is only deep enough to 

extinguish burning oil. The bottom of this pit is sloped for good drainage to the drainpipe leading 

to an open containment pit. This latter pit is sized to handle all the oil of the largest piece of 

equipment in the station. A cross section of the system is shown schematically in Figure 6-3. The 

trap shown in Figures 6-4 and 6-5 is designed to contain the total capacity of oil on top of the 

water.

To maintain a dry system in the collecting units, the other side of the intake pipe from the 

containment pit should be at least the maximum elevation of the oil level. In areas of the country 

subject to freezing temperatures, the trap, or skimmer, should be encased in concrete, or other 

such available material, to eliminate heaving as a result of ice action.

Figure 6-2: Typical Oil Drainage System for 345/138 kV Outdoor Substation
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Figure 6-3: Cross Section of Oil Drainage System

Figure 6-4: Oil Trap or Skimming Unit
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Figure 6-5: Oil Trap in Containment Pit

An alternate method of constructing an oil trap is shown in Figure 6-6. The trap in this method is 

fabricated with three- to four-inch PVC pipe. Galvanized pipe is not recommended for use for 

subsurface work because of corrosion and subsequent loss of the pipe.

a. Advantages

• Relatively inexpensive

• Easily maintained

• Provides additional substation drainage

• Reliable

b. Disadvantages

• More substation area required

• Unsightly, possible hazard to personnel and equipment movement

• May have possible insect breeding problems
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Figure 6-6: Oil Trap Construction Using Galvanized or PVC Pipe

6.6 POLYMER AGENTS

6.6.1 Imbiber Beads®* Imbiber Beads® are spherical plastic particles, each about the size of a 

sugar granule, that are engineered to imbibe/absorb a wide range of compatible organic liquids, 

including diesel fuel, gasoline, hydraulic fluids, crude oil, aviation fuels, chlorinated solvents, 

cable oils, and most transformer oils. Imbiber Beads® are unique to the entire sorbent industry in 

that liquids physically diffuse into their solid structure, which causes them to swell up to three 

times their original size. In doing so, they will absorb up to 27 volumes of liquid for each volume 

of Imbiber Beads®. Once a liquid is “imbibed,” it is no longer available for release back into the 

environment. This has decided benefits during spill response operations, as secondary 

contamination is eliminated—saving both time and money—and potentially hazardous vapor 

release is reduced by 500 percent to 600 percent that of other sorbent (adsorbent) materials. 

Imbiber Beads® also are unaffected by water and will selectively remove oils from water.

The swelling characteristic of Imbiber Beads® allows them also to be used in preventive 

measures such as gravity-flow drain protection in areas at risk, such as transformer substations, 

motor pools, fueling areas, storage areas, service yards, and bulk storage tanks. Water will 

percolate through the void spaces between the Imbiber Beads but when contacted by a

* Imbiber Beads® is a Registered Trademark of Imbibitive Technologies Corporation
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compatible oil product the Imbiber Beads® swell, effectively closing off the leak path and sealing 

the drain.

Imbiber Beads gravity-flow drain protection systems are available in various sizes and design 

configurations to accommodate a wide range of requirements, including flow rates. The systems 

are all-inclusive and consist of a standard size, galvanized or stainless steel housing and various 

component parts, all of which are easily changed out either following a release event or as part of 

routine maintenance.

1. Top grate with silt fabric cover for silt collection and various debris

2. Imbiber Beads/Sand Discs (2) to absorb incidental amounts of oil along with silt filter 

cover

3. Imbiber Beads “pillows” to absorb run-off amounts of oil—up to three gallons

4. Imbiber Beads Shut Off Disc (1)—14" diameter containing bulk Imbiber Beads

The Imbiber Beads Disc provides a positive shutoff mechanism in the event of a catastrophic 

release. These systems have no moving parts and require no electronic sensors or electricity. 

(Figures 6-7 and 6-8).

A similar Imbiber Beads gravity-flow drain protection system also is available to allow water to 

drain from diked or curbed areas but still provide protection in the event of a release. The 

Imbiber Beads curb system is designed to be inserted into a cutout section of the curb or dike 

wall (Figure 6-9).

Figure 6-7: Imbiber Beads

® 

Gravity-Flow Drain Protection System–Operational Process
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®

Figure 6-8: Example of an Imbiber Beads Gravity Drain Protection System

®

Figure 6-9: Imbiber Beads Gravity-Flow Drain Protection System—Curb Application

Other Applications:

Imbiber Beads “spin-on” valves are used in conjunction with oil-water gravity flow separators 

for the safer discharge of water from these separators. The spin-on valves are available in plastic 

(100 percent HDPE) and fasten to a 2" outlet pipe. Imbiber Beads pillows and blankets are used 

in “sit and soak” situations as preventive maintenance where oils and fuels are known to collect 

or where weeps occur. They also are used to prevent oil releases that could cause a visible sheen 

on surface waters at outfalls.

6.6.2 CI Agent

CI Agent is a nontoxic, nonhazardous, noncorrosive, noncarcinogenic, environmentally friendly 

petroleum-based blend of polymers, used to immobilize petroleum and related petrochemical 

emergencies related to releases on land and water.

CI Agent is a dry granular powder specifically blended to encapsulate petroleum-based liquid 

spills through the rapid transformation of a liquid material into a cohesive rubber-like mass upon 

contact. It has met all the criteria for being listed on the Environmental Protection Agency’s 

National Contingency List Product Schedule. Unlike absorbents that soak up a liquid through 

expansion, CI Agent solidifies the liquid into a removable mass with minimal volumetric
Bulletin 1724E-302 

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increases and retains the liquid for easier removal. This eliminates the “dripping” effect that 

results when absorbent materials do not allow the liquid to escape or to be squeezed out, thus 

greatly minimizing any residue or contamination.

The application rate may vary with the viscosity of the liquid; however, to solidify a hydrocarbon 

normally requires a ratio of 4 to 1 CI Agent. The pickup ratio and speed of solidification will 

vary with the type of hydrocarbon, the amount of volatiles remaining, temperature, and the 

viscosity of the liquid.

Solidification capacity of one pound and one gallon of CI Agent:

Hydrocarbon Tested Capacity of One Pound Capacity of One Gallon

Gasoline

Diesel

5.42 lbs

4.89 lbs

2.3 gallons

2.1 gallons

10w30 Motor Oil 1.64 lbs 0.7 gallons

Transformer Oil 4.01 lbs 4.5 gallons

Enamel Paint 1.54 lbs 0.7 gallons

The product can be purchased in a variety of forms:

6.6.2.1 CI Agent barrier booms allow utility companies to quickly and easily boom all or part 

of their perimeters to help meet federal SPCC regulations of secondary containment and 

diversion at a fraction of the cost of alternative methods. CI Agent barrier booms will not allow a 

hydrocarbon to leave the facility, while allowing water to pass through. Should an oil release 

occur, the booms will instantly solidify the oil, thus becoming an impervious barrier to keep the 

oil on the property, until the incident can be responded to.

6.6.2.2 CI Agent barrier mats afford the same protection and can be quickly and inexpensively 

placed around the slab of a pad mount or other pad-mounted equipment, to contain any leaks or 

to stop releases from reaching the soil or leaving the immediate area. All CI Agent barrier booms 

and mats are custom-designed and manufactured to meet customer specifications.

6.6.2.3 CI Agent hydrocarbon flow barriers (HFBs) easily become a preventive method at 

new or existing gravity-flow drains at any type facility. HFBs allow rainwater to pass but collect 

any low parts per million of sheen from the water. HFBs also close down drains when activated 

by a major oil release. An HFB is available in all types of design, including curb and dike 

configurations, various flow rates, and size requirements to accommodate a wide range of 

applications. Requiring no electricity and having no moving parts, CI Agent HFBs become a 

cheap insurance policy against accidental spills or catastrophic releases.

6.6.2.4 CI Agent in loose powder form can be used for water- or land-based spills. CI Agent 

floats on the surface of the water and will not sink even after it has encapsulated a liquid. If a 

spill is emulsified to the point of sinking, CI Agent could be introduced below the level of the 

spill and as it rises to the surface will pass through the emulsified waste and bring it to the 

surface in an encapsulated form, thus easing the complexity of recovery. The suggested method 

of dealing with an open water spill would be to completely surround the spill with CI Agent,
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spreading the product on the outer edge of the spill. If the normal absorbent (leaching type) 

booms have been used, use CI Agent as a barrier between the booms and the spill to prevent the 

spill from reaching the booms. Once the spill is contained, the liquid inside the CI Agent can 

either be recovered for reclamation or additional CI Agent can be spread over the entire spill for 

complete solidification, and ease of removal with the least amount of waste.

For land-based spills, CI Agent can be used for building a perimeter or dike around the spill to 

prevent further migration of the liquid into drains, ditches, or waterways. This presents the 

opportunity to reclaim the liquid. If full immobilization is necessary, CI Agent can be broadcast 

over the entire area to form a cohesive, rubber-like “carpet” for easy removal by shovel, loader, 

or other suitable method and placed in waste disposal or end-use application containers.

6.7 OIL SEPARATOR TANK

This system is feasible only when there is sufficient gradient for gravity discharge from the 

underground tank. The oil and water are collected from the equipment area and are discharged 

into an oil separator tank. The principle upon which this system operates is that oil is lighter than 

water and floats above it.

The oil separator tank should be designed to contain all of the oil in the largest single piece of 

equipment should a major rupture occur (Figures 6-10 and 6-11). These tanks may be formed 

and poured in place, or a precast septic tank may be purchased and slightly modified. This 

system allows the water to continuously pass through but retains the oil. The oil retained in the 

tank must be pumped into a tank truck and disposed. The oil separator tank principle also may be 

applied to above-grade diked basins if freezing temperatures are not prevalent.

Figure 6-10: Typical Construction of Oil Separator Tank
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Figure 6-11: Transformer--Accumulating Tank Combination

To avoid improper operation of this system, it is necessary that the water level not be allowed to 

drop below the bottom of the discharge pipe inlet in the tank. All oil separator discharge pipes 

should be vented in order to maintain atmospheric pressure in the tank, thereby preventing any 

possible siphon effects.

Modification of the above-grade separator system may be considered if regular inspection is 

performed. It could consist of a transformer area that is lined and dike with impervious material.

a. Advantages

• Reliable

• Easily maintained

b. Disadvantages

• Relatively expensive

• Requires periodic maintenance

• Discharge pipe outlet may be inoperative during freezing temperatures

6.8 OIL STOP VALVE

The previously described oil separator tank system can be slightly modified by the use of oil stop 

valves to greatly improve the system’s reliability.

The valve’s only moving part, a ballasted float, has a specific gravity between that of oil and 

water. When oil spill conditions occur, the float loses buoyancy, sinking in the higher level of oil 

until it seats itself on the orifice to the discharge outlet.

As the spill conditions are corrected, the float rises and water is allowed to pass through the 

orifice. If the oily water includes neutral buoyancy material—such as suspended particles—that 

might interfere with the seating of the float, screening may be installed (Figure 6-12).
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a. Advantages

• Smaller catch basins are required since oil can be maintained on property

• Relatively inexpensive

• Direct acting

b. Disadvantages

• Possible clogging

• Periodic inspections required

Figure 6-12: Oil Stop Valve Installation

6.9 GRAVEL-FILLED EQUIPMENT PITS

This method of oil retention provides a total means of oil containment. Refer to Figures 6-13, 6-

14, and 6-15. The size of the pit surrounding each piece of equipment must be sufficient to 

contain the spilled oil in the air voids between the aggregate of gravel fill or stone. The pit 

should be lined with compacted clay, concrete, or a liner. A gravel gradation with a nominal size 

of three-quarter-inch to two-inch, which results in a void volume between 40 percent and 45
Bulletin 1724E-302 

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percent of the pit volume should be used. A more accurate value of the void volume may be 

obtained from the stone supplier or by estimating the specific gravity of the solid and density of 

the material and using the formula:



Void Volume (porosity), % = 1 − 

62.4G



100

SP 

where GSP = specific gravity of the solids

(varies from 2.6 to 2.8)

∂ = dry density of gravel fill, pounds

per cubic foot (varies from 80 to 110)

For some limestone and sandstone, the GSP and values may be lower. The theoretical

maximum amount of oil that can be contained in 1 cubic foot or yard of stone is given by the 

following formula:

 void volume, %

Oil, volume, gallons = 100 x 0.1337 cu. ft. 

where 1 gallon = 0.1337 cu. ft.

In the case of the three-quarter-inch gravel, the estimated volume of gravel needed for a 40 

percent void volume of stone to contain the oil from a 1,000-gallon transformer is:

40 = 3.0 gallons/cu ft

100 x .01337

and

1,000 gallons = 334 cu. ft. of gravel fill 

3.0

This indicates that approximately 12.4 cubic yards of gravel fill is required in order to properly 

contain the entire volume of oil contained in a 1,000-gallon transformer.

If pits are not automatically drained of rainwater (see Section 6.10, Oil Containment Pits), an 

additional allowance must be made for precipitation. The additional space required will depend 

on the precipitation for that area and the frequency at which the facility is periodically inspected. 

It is generally recommended that the pits have sufficient space to contain the amount of rainfall 

for this period plus a 20 percent safety margin. Appendix B should be consulted to determine the 

normal precipitation for any particular area.

For instance, if the Galveston, Texas, transformer facility above is to be inspected monthly, and 

if the overall dimensions of the pit and transformer foundation are not to exceed 12 feet by 10 

feet, the additional precipitation allowance can be calculated as follows:

Maximum monthly precipitation (Appendix B, Page B-10) = 5.76 in. 

Volume of precipitation = 144 x 120 x 5.76 = 99,533 cu. in.

∂
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Vol. of precipitation plus heavy rain allowance = 99533 x 1.20

= 119,439 cu. in.

= 69.1 cu. ft.

The volume of stone needed to contain 69.1 cubic feet of water assuming 40 percent void 

volume is:

69.1

0.4 = 172.8 cu. ft. = 6.4 cu. yd. of stone

Therefore, the approximate volume of stone needed to contain 1,000 gallons of transformer oil in 

a manual drain pit is 18.8 cu. yards (12.4 + 6.4).

The area directly surrounding the pit must be graded to slope away from the pit to avoid filling 

the pit with water in times of rain.

Figure 6-13: Plan View of Equipment Pit
Figure 6-14: Details of Equipment Pit

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Figure 6-15: Typical Drain Pit
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6.10 OIL CONTAINMENT PITS

A common and reliable method of preventing spills and ensuring that oil will be contained on the 

substation property is to place all major substation equipment on or in concrete containment pits. 

These pits will confine spilled oil to relatively small areas, which in most cases will greatly 

reduce the cleanup costs. Figure 6-16 illustrates one method of pit construction that allows the 

equipment to be installed at grade level.

Figure 6-16: Oil Containment Pit

Berms or dikes as shown in Figures 6-17 and 6-18 have maintenance disadvantages but can be 

constructed relatively easily after the equipment is in place at new and existing electrical 

facilities.

a. Advantages

• Limit possible damage to adjacent equipment

• Minimize cleanup costs

• Require minimum amount of land

• Below-grade pits provide noise abatement

b. Disadvantages

• Expensive

• Require periodic maintenance

• Require energy to operate

• May require higher adjacent conductor supporting structure to maintain electrical 

vertical clearances
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Figure 6-17: Transformer Dike
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Figure 6-18: Dike, Sponge Area, and Stile Details

6.11 SUMP PUMPS

The sump pump can be manually operated during periods of heavy rain or it can be automatically 

operated. If automatic operation is preferred, special precautions must be taken to ensure that oil 

is not pumped from the pits. This can be accomplished with either an oil-sensing probe (Figures 

6-19 and 6-20) or by having all major equipment provided with oil limit switches—an option 

available from equipment suppliers. These limit switches are located just below the minimum top 

oil line in the equipment and will open when the oil level drops below this point.
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Figure 6-19: Above-Grade Sump Pump Discharge

Figure 6-20: Schematic Diagram of Sump Pump Control Using Equipment Oil Limit

Switch or Oil Sensing Probe
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6.12 GATE VALVES

Pits may be emptied manually by gate valves depending on the facility terrain and layout, or 

automatically implemented by the use of equipment oil limit switches and DC-operated valves. 

The DC valve operation (Figure 6-21) allows surface water to normally run from the pit and 

closes when the oil level drops within the protected device.

Figure 6-21: Motor-Operated Gate Valve
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CHAPTER 7

OIL CONTAINMENT IN NAVIGABLE WATERS

This chapter is for oil containment after it reaches navigable water. New regulation does not 

change or address this issue.

7.1 GENERAL

Containment is perhaps the most important act in the removal of an oil spill, as it is used to 

prevent the spread of the oil, thus minimizing environmental damage. Successful containment is 

highly dependent on response time, which, in turn, depends on many variables. Some are 

permanent variables: geographic features that limit access to a spill, equipment design and 

availability limitations, and personnel capability. Other factors affecting response time will 

change with each spill: time of notification, size of spill, physical and chemical properties of the 

spilled oil, and climatic conditions at the time of the spill.

When designing a containment system for a given area, the exposure to spills should be 

considered first, followed by the permanent variables mentioned above. This review should 

narrow the choice of equipment to that best suited to meet a particular area’s limitations. To a 

certain extent, personnel capability can be improved, and the other spill variables can be 

anticipated through training in spill drills at various times of the year.

This section deals with the principal methods or systems used to contain a spill on inland or 

coastal waters.

7.2 BOOMS

An oil boom is a man-made unit placed on water to serve as a barrier to the movement of oil 

across a designated plane. Many different types, shapes, and sizes of booms are being used, and 

research continues to improve their use and performance. A boom basically traps floatable 

material at the surface while, at the same time, permitting the flow of water under the debrisformed dam. These five components, shown in Figure 7-1, should be considered when selecting 

a boom that is used for oil spill containment or to direct flow:

• Float

• Skirt

• Tension member

• Ballast or weighting member

• Coupling
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Figure 7-1: Components of a Boom

7.2.1 Floats

The principal component of all booms is a flotation device that keeps the unit afloat and, in many 

instances, acts as a barrier in conjunction with the skirt. Floats vary in size and shape depending 

on use and need. Some circular floats are as small as three inches in diameter and range upward 

to more than three feet in diameter. Booms are manufactured with detachable floats, air inflatable 

floats, or inseam floats.

The type and shape of the float are major factors in the selection of a boom, as they will 

determine whether the boom can or cannot be stored on a reel. Some floats will cause a storage 

problem because of bulk and/or the need to “accordion” the floats because of their rigidity. 

Another problem with some floats is their erratic behavior when deployed and towed at moderate 

speeds. The type and shape of float also will determine the ease of transport and recovery.

Porous floats will absorb a medium- to lightweight oil, making the cleaning of the boom after 

use more difficult. These types of floats can be protected with a vinyl cover and/or sealed by 

paint or another compound that can be cleaned much more readily.

For noninflatable floats, polyethylene foam is generally used as the float material.

Air or gas-inflated float booms are more durable, but more expensive than the plastic float types. 

The inflated type float provides maximum buoyancy and, when collapsed, is more easily handled 

and stored.

Although carbon dioxide gas from pressurized cylinders can be used for inflation, a more 

common method is the use of compressed air, requiring engine-driven compressors. 

Disadvantages of inflatable flotation range from possible escape of gas or air from leaks, 

ruptures, and/or possible poor heat seals.
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Other types of boom floatation have been used but are generally associated with local 

improvisation and ingenuity. For example, logs have been joined together with cables to form a 

barrier. Booms also can be built from sealed metal drums joined to plywood sheets using steel 

cables. These booms tend to be very awkward to handle and deploy, and are not generally 

recommended except during emergencies.

7.2.2 Skirts

The primary purpose of a skirt is to serve as a dam or barrier with the float during containment. 

The skirt often extends above the water, becoming part of the float section, thereby sealing the 

section between floats. Skirt characteristics that should be considered when selecting a boom are:

a. Fabric—Some booms have a plastic skirt, some a rubberized or neoprene-covered 

laminated material. Most use a vinyl-coated nylon or polyester fabric. This light fabric 

will permit a more collapsible skirt, while a heavy fabric will tend to stiffen the 

vertical plane. Usually, the heavier the fabric, the more ballast or weighting material 

that can be added. The fabric should always be cleaned and rinsed after each use. 

Storage of the boom usually requires it to be folded between floats. This bending and 

unbending requires a flexible material to prevent damage to the boom.

b. Depth—The skirt acts as a fin when being towed and as a barrier when placed in 

position. Therefore, specifying the depth of the skirt of the part that is to be submerged 

is an important decision to make in selecting a boom. If the boom is to be towed great 

distances and at moderate speeds, a shallow skirt is more desirable. A longer or deeper 

skirt will contain a greater amount of floatable material. However, deeper skirts will 

have more pressure exerted on them by currents or tides and, therefore, will be more 

difficult to deploy and control. A skirt of less than six inches is considered impractical 

except for special uses.

c. Tensile Strength—The horizontal tensile strength of the skirt—the ability to withstand 

pulling pressure—is limited, so care should be exercised not to exceed this strength 

unless the boom is reinforced with additional tensile strength members.

d. Flexibility—A collapsible or flexible skirt fill permits the boom to seal off a spill in 

very shallow waters and across a sloping beach or shoreline. A rigid or vertical skirt 

will lie down and permit the spill to escape.

7.2.3. The Tension Member

This member determines the deployable length of a boom. The function of this member is to 

evenly distribute the horizontal load that may be imposed on it from currents and wind 

conditions. Dacron straps, steel cables, and chains are materials more commonly used as tensile 

members (Figure 7-2).
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Figure 7-2: Boom Tension Members

(A) Bottom Chain, (B) Inseam Cable, (C) Dacron Straps, (D) External Cable

7.2.4 The Ballast Member

Most oil booms have a ballast or weighting member along the bottom edge of the skirt. When a 

boom is deployed, the ballast keeps the skirt in a more vertical position, permitting it to act as the 

required barrier. A more vertical skirt is more easily towed and positioned. An unweighted skirt 

will readily plane in very low currents. Ballast weight will vary depending on water currents 

where the boom is used and on how the boom is used. The deeper the skirt and the higher the 

current, the more ballast that will be needed.

Ballast need not be a completely fixed part of the boom, but can be attached in several ways. On 

some booms, ballast can be added to grommets in the skirt or to the chain or cable at the base of 

the skirt. In some cases, the chain or cable serves the dual purpose of ballast and tension member 

and, as such, it must be free for the full length of the section. Ballast should be attached to the 

boom with minimum looseness to prevent wear and tear of the skirt material or holding straps 

during handling.

7.2.5 Couplings

Booms usually can be selected in 50-foot, 100-foot, and 200-foot sections. Some air inflatable 

booms can be purchased in sections up to 1,600 feet long.

When shorter sections are purchased, the coupling for them should be considered. A coupling 

that can quickly and effectively unite two boom sections could be one of the most important 

factors in determining response time. Couplings that do not fit properly, or those requiring off-
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site adjustments, can and will cause delays, possible leaks at the union, and in certain cases even 

rejection of the entire section (Figure 7-3).

Unfortunately, there is no standard boom coupling. Some manufacturers have standardized 

specific boom sizes and couplings so that a deployed boom may contain sections manufactured 

by several companies.

Nearly all couplings are rigid, extending from near the top of the float to the base of the skirt. A 

coupling will cause the union section to be rigid. As a result, a collapsible skirt with a coupling is 

not effective in waters shallower than the skirt length. Proper care of the coupling unit is 

essential, as a bent or corroded bolt section may require that the section be discarded.

Figure 7-3: Boom Couplings

(A) Metal Interlock (Slickbar), (B) PVC Joint, (C) Bolted Overlap

The five principal components of a boom have been reviewed but these other factors should be 

considered when selecting a boom design.

7.2.5.1 Length: Boom manufacturers usually carry a limited number of standard sections, 

requiring the purchaser to specify not only the type but also the section lengths. Lengths other 

than standard are usually more costly. Standard lengths vary between manufacturers but are 

mostly in the 40-foot, 50-foot, and 100-foot range.

7.2.5.2 Factors Affecting Deployment: Deploying a boom on perfectly still water—say, on an 

enclosed swimming pool—is simple. However, the actual deployment of booms to serve as 

barriers to floating oil is more complex because of many natural variables. These variables 

include water pollution, current, wind, physical and chemical properties of the oil, water and air 

temperatures, water depth, accessibility to the spill site, source and magnitude of the spill and, 

finally, the type, size, and length of boom available.

7.2.5.3 Current: Floating oil will move in the same general direction and at nearly the same 

speed as the carrying body of water unless there are offsetting forces such as wind and/or 

deflecting objects in the path of the current. Any barrier, such as a boom, placed directly across 

the flow will be exposed to maximum forces on the skirt—that part below the surface. This load 

can be great enough to sever the tensile members. The current load also may exceed the vertical 

load applied by the ballast of the boom, resulting in “planing” of the skirt, which will release any 

trapped oil (Figure 7-4).
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Figure 7-4: Boom “Planing” in Current

I. In low current situation, oil is held by each boom type: (A) weighted flexible skirt,

(B) rigid skirt, and (C) bottom tension.

II. In high current, the flexible skirt (A) experiences partial failure, the rigid skirt, (B) is 

planing with current, with almost total failure, while the bottom tension (C) is still holding

most of the oil. (Note: This does not consider escape by entrainment. See below).

The current forces against a deployed boom can be calculated by the following formula: 2

F = 0.92DwV w

where:

F = Forces, lb/lin. ft.

Dw = Depth of skirt, vertical feet into water 

Vw = Velocity of water, ft./sec.

In using this formula be sure to consider:

• True depth of skirt. If the current forces are great enough to cause some planing, the 

true vertical depth will be less than the actual length of the skirt.

• Average water velocity. Measure the water velocity at several points near the surface 

and at the bottom of skirt depth and then average. These velocities can vary markedly.

Note: Winds also will affect the direction and rate of movement for oil floating on water; 

both forces must be considered when deploying a boom (see 7.1.5.4, Wind).

Spills in high-current waters present difficult control problems requiring specialized directional 

boom equipment that needs to direct the oil to the quieter waters near shore where it may be
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more easily removed. Such a directional boom must be long enough to reach well out into the 

water, which increases the load on the boom, requiring great tensile strength. It is likely that 

some of the oil will escape the first boom, making deployment of a second boom in a 

downstream location necessary.

Many times, the currents along the banks will be deflected by submerged objects, resulting in 

eddy currents. This may even move water near the bank in a flow in the opposite direction of the 

flow in the center of the stream or channel. This reverse flow will naturally influence the 

trapping capability of a deployed boom.

7.2.5.4 Wind: The forces exerted by wind play a major role in oil spill containment. Factors that 

affect wind-moved oil on water include water current, the physical properties of the oil, and the 

spill size. Generally, wind will move most oil over water at a rate of 3 percent of the wind 

velocity. For example, with a 33-mile-per-hour wind and no current, the floating oil can be 

expected to move with the wind at a speed of approximately 1 mile per hour. This may not seem 

like much, but it amounts to 880 feet in 10 minutes. Thus, wind-driven oil requires a prompt 

response with a quickly deployable boom. Figure 7-5 shows some of the possible effects that 

wind may have on the movement of oil.

Wind also will exert a substantial force against the float or sail portion of a deployed boom. 

These forces should be considered when selecting a boom for deployment. They can be 

calculated as follows:

where:

w w2

F = 0.00339V H

w

F = Force exerted against float, lbs/lin. ft. w

V = Wind Velocity, knots

H = Height of float above water, ft.

Winds create waves and chop, which greatly affect the efficiency of oil booms. Most booms used 

in coastal areas will contour well to waves where the length-to-height ratio is about 8:1. Boom 

performance will deteriorate as this ratio lessens. Rollover of rigid booms and submergence are 

common experiences when a boom is deployed in windy and choppy waters.

When wind and current are working together, the total load on a deployed boom will be the sum 

of the two forces. Applying the proper restraints, depending on the angles involved, can 

compensate for tangential forces.

A floating barrier deployed across a moving body of water to trap floating oil experiences a wellknown behavior: submerged escape. A skirted boom acts much like a dam and assumes a natural 

catenary configuration. Floating oil will then accumulate at the turbulent base of the catenary. If 

the current is at or below 0.7 knots, oil will begin appearing downstream and eventually all of the 

trapped oil may escape.
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Figure 7-5: Wind Effect on Oil Movement

A deployed barrier or dam interferes with the flow of surface waters down to the depth of the 

boom skirt. To escape this trap, the surface water must increase its velocity and travel under the
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skirt. As the velocity of the surface water increases in its downward plunge, the floating oil 

travels with this water under the boom. The greater the stream or tidal current, the more 

turbulence there is and the more trapped oil that will escape. Currents that do not exceed 0.7 

knots usually do not cause oil loss under the boom. This is probably because the downward 

forces are not great enough to affect the gravitational differences between the water and lighter 

oil.

In streams, rivers, or channels with current velocities of 2 knots or more, spilled oil will usually 

accumulate in the quieter bends of the water channels or along the shallower and less rapid 

waters near the banks. This greatly aids the cleanup insofar as selecting where to deploy a boom 

to best trap the floating and moving oil (Figure 7-6).

Figure 7-6: Action of Spilled Oil in Fast Current Rivers

(A) Oil moves to lower current waters along the banks where it can be contained.

(B) In river bends, oil will move toward outside radius bank, allowing containment.

A wind-moved oil spill will finger disperse more readily than a current-moved spill. The wind 

will tend to push only the surface of the oil spill and not the entire mass, while a current will 

carry the entire spill along with it. Where differing oil thicknesses exist, the difference between 

the surface tension of the water and the oil plays a significant role in the amount of fingering.

Wind can be a valuable tool to the cleanup contractor if used properly. Its force on floating oil is 

usually positive, with reasonably predictable results. Using a boom to guide or direct the wind or 

current-moved oil to a pickup center is most effective, quick, and inexpensive. However, 

crosswind or crosscurrent deployment of boom or wind will subject a boom to maximum load 

forces and risks partial to total failure. On the negative side, winds can change direction and 

speed quickly, drastically adding to the problem of boom selection and deployment.
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7.2.5.5 Water Depth: Either a rigid or collapsible skirt boom may be deployed in water that is 

deeper than the depth of the skirt at all times with allowance being made for tidal differences. 

However, if one end of a boom needs to be onshore, near shore, or where the skirt will be 

exposed during low tide, a boom with a collapsible skirt should be used if available. Such a skirt 

will collapse on the slope of the beach, maintaining a barrier at the water’s edge. A rigid skirt 

will fall flat and permit the trapped oil to escape unless a trench is dug into the beach or bank 

deep enough to bury part of the boom and keep the oil from escaping (Figure 7-7).

Deep water can cause problems in anchoring a deployed boom. Properly securing a boom 

deployed in deep water—more than 40 feet—requires the use of large anchors, with long lengths 

of rope. These extra requirements increase equipment needs and response time (Figure 7-8).

Figure 7-7: Flexible vs. Rigid Skirts

(A) A flexible boom skirt will collapse on the beach slope, trapping the spill. (B) A rigidskirt boom will fall over, allowing the oil to escape. (C) When a rigid-skirt boom is put into

a trench, it can remain vertical and trap the spill.
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Figure 7-8: Anchoring a Boom in Deep Water (Not to scale)

The length of the line from the boom buoy to the anchor should be at least five times the 

depth of the water.

7.2.5.6 Accessibility and Response Time: The ideal oil spill incident for the cleanup contractor 

is the one reacted to soon enough to contain the source and prevent spreading. This, of course, 

requires prompt notification and response. Not many incidents fall into this category.

Usually the call for service is delayed because of darkness, inclement weather, or dependence on 

practices “as usual.” A 30-mile-per-hour wind can move the spill a distance of 1 mile in 1 hour. 

Delays in response often are the single most serious cause for any impact an oil spill may have 

on the environment.

During free movement on water, oil may find its way into more inaccessible areas, where 

cleanup is more difficult. Controlling the oil with booms during its movement can prevent this by 

directing the spill to better recovery areas.

A pipe-type cable break will present a major problem, as this source is not easily accessible and 

the spill will continue until the pumping has been stopped and the line has lost its oil, This type 

of spill can occur anywhere along a cable right-of-way and may not be detected until a pressure 

drop is evident or the actual spill has been reported. Pipe-type cable spills can be entirely landlocked, near lakes, creeks, or rivers or in the bays and estuaries of a coastal region. A diversity of 

boom types, lengths, and sizes is needed to cope with these possibilities. Boom selection for this 

purpose will depend on exposure.

7.2.5.7 Boom Application: There are two primary methods of developing a boom: stationary, 

with the boom anchored or held in place; and moving, with the boom moved over the water’s 

surface by vessels or, in certain cases, by wind forces.

The vast majority of spill situations will call for a stationary boom deployment. In certain 

situations, a moving deployment can provide quicker and easier recovery of spilled oil. However, 

moving deployment generally requires much more experience in boom and boat handling than 

stationary deployment. Also, it can more easily end in the loss of trapped oil if diligence and care
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are not taken during all phases of the operation. In stationary deployment, wind and current act 

to destroy the effectiveness of the boom. As noted earlier, high winds or currents of 0.7 knots or 

more will carry oil under a conventional boom. With low current and/or wind velocities, boom 

deployment directly across, or perpendicular to, the flow will contain the spill.

Figure 7-9: Suggested Boom-to-Shoreline Angles for Different Current Velocities

With a current of about 0.85 mph, the angle can be 60°. A current of 1.5 mph requires a 30° 

angle. A current of 2.75 mph can be handled with a 15° angle. When stream current velocity 

exceeds 3 mph, seek out bends or other places where the current naturally slows down to a more 

reasonable speed.

To cope with those situations involving water velocities above the magic 0.7 knots, booms can 

be deployed at an angle to the flow. This type of deployment will reduce the force against the 

boom and direct the oil along the side of the boom to a collection point, usually the shoreline, but 

often a floating skimming device.

The smaller the angle between the collection point and the boom, the greater the current 

toleration. See Figure 7-9.

When a boom is used as a directional device, anchoring along its length should be avoided 

whenever possible. Figure 7-10 illustrates some of the problems that can arise in such a situation.
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Figure 7-10: Possible Problems Caused by Improper Boom Anchoring

(A) If a deflection boom is allowed to form a deep catenary configuration between 

anchoring points, some of the oil will remain trapped in these pockets.

(B) If a containment boom is allowed to form a catenary, the oil will collect in the catenary, 

rather than move to the shore. In either case, recovery of the oil is much more difficult.

7.2.5.8 Moving Deployment: When the body of water is wide enough or the oil is moving near 

the center of a stream, deploying a boom directly across the path of the spill can contain it 

(Figure 7-11). The boom should be controlled at each end by a vessel that can easily maneuver in 

the particular waters. The boom should be allowed to form a deep catenary configuration to trap 

the oil at the base of the catenary. As the oil reaches the boom, the entire trap and vessels should 

move downstream—downwind—at near the speed of the current (wind) holding the spilled oil 

within the catenary arc. Care should be taken not to pull one end against a current, as this will 

cause the skirt of the boom to plane, releasing the trapped oil.

At an opportune time and place, one end of the boom can be moved ahead, carefully maneuvered 

toward the shoreline and tied. Meanwhile, the other end can be moved somewhat upstream 

(upwind) from the tied-down end. The oil then is allowed to slide downstream (downwind) along
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the side of the boom to where it will concentrate and can be removed. A successful operation of 

this type needs practice and expert boat maneuvering.

Figure 7-11: Moving Deployment

A boom is held in a catenary between two boats, which move downwind (down current) at 

or near the speed of the wind (current)

7.2.6 Special Situations

Debris often accompanies floating oil, particularly in streams and rivers, but to some extent in all 

watercourses. This debris can cause removal problems by clogging most recovery devices and/or 

by absorbing the oil. Large pieces or great amounts of debris can pile up behind a boom, raising 

the skirt enough to allow the trapped oil to escape, damaging the boom or even breaking it.

When containing a spill in a high debris location, special precautions have to be taken. Double or 

even triple booming may be necessary. Alternately, a debris “fence” could be deployed upstream 

of the containment boom, with a crew stationed to clean off the debris as it piles up.

Since the deployment of a boom is controlled primarily by the direction and speed of current 

and/or winds, rapidly changing winds or currents—such as ebb and flood tides—will create 

difficulties in keeping the spilled oil contained.

Knowledge of the behavior of the changing currents and winds peculiar to a specific area is 

paramount in determining how and where to deploy containment booms. This knowledge can be 

gained from local experts through trial runs and maintained with periodic drills. To ensure
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containment, more than one length of boom will need to be deployed. Figure 7-12 illustrates one 

method to use or consider in such a situation.

Figure 7-12: Changing Currents

If a spill occurs during ebb tide, with a prevailing wind as shown, the primary containment 

boom would be deployed at A. A secondary boom would be deployed at B to maintain 

containment during flood tide. (Note: During flood tide, the secondary boom would assume 

the shape shown by dotted line at C.)

7.3 CONTAINMENT DAMS

Although the deployment of floating booms is by far the most-used oil spill containment method, 

other types of containment will be more effective and easier or cheaper to accomplish at other 

locations and in different situations. Streams, creeks, and other small drainage channels—usually 

in inland areas—are often too narrow, too fast-moving, and/or too steep-sided for proper boom 

deployment. For spills on these types of waterways, containment dams constructed from either 

earth or absorbent materials offer a good choice for trapping the oil.

7.3.1 Earthen Dams

An earthen dam can be constructed quickly across a dry creek bed using a bulldozer, dragline, or 

backhoe. If necessary, a crew of workers can build the dam with shovels, but this method is not
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recommended except in extreme emergencies. In any event, lead time—the amount of time 

before the spill is expected to get to the containment site—is critical. When selecting a dam site, 

it is necessary to choose a location far enough downstream to be able to finish the dam before the 

oil arrives.

In constructing the dam, place two or more drainpipes or culverts near the base, positioned in the 

direction of the stream flow. These pipes need to be longer than the width of the dam at its base, 

and should have a diameter large enough to allow passage of the water without causing it to back 

up higher than the dam. Multiple drainpipes are used to control the water flow. By plugging one 

or more of the drainpipes, the water can be maintained at the proper level to keep the oil afloat,

yet trapped behind the dam. Installing the pipes on a slant also can help control the water level 

(Figures 7-13 and 7-14).

Figure 7-13: Earthen Dam, Cross Section

Multiple pipes near the bottom with valves to control the flow and retained depth of the 

water.

Figure 7-14: Earthen Dam, Cross Section

Pipes installed on an incline to control water depth. The top of the incline determines the 

height of the retained water and oil.

Once drainpipes are in place, the remainder of the dam can be built up to the desired height, 

being sure to keep the earthen material well compacted during construction. The final height 

should be just enough to trap the oil. The width across the top will depend on the need for 

equipment and personnel to cross the dam.
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7.3.2 Straw or Sorbent Dams

Occasions will arise when floating booms or earth dams are not practical for containing a 

floating spill on a shallow and relatively narrow creek or streambed. In this situation, a straw or 

absorbent dam can be constructed.

This type of dam can be constructed readily in shallow running water from materials usually 

available in any community. Across a deeper body of water, hanging the barrier to a cable 

suspended across the stream will accomplish the containment. In the latter case, weights will be 

needed to keep the base of the barrier from planing downstream, releasing the absorbent and oil. 

(Figure 7-15).

A sorbent barrier is constructed by first stretching a wire fence across the stream and anchoring it 

firmly at each bank. The wire may be chicken, hog-type, or chain-link, but it should be dense 

enough to prevent straw or other sorbent materials from washing through it easily. The wire 

fence can be kept vertical by driving steel support posts or pipes into the streambed at 8- to 10-

foot intervals. Once the fence is erected, straw can be scattered across the upstream side to a 

depth of 4 to 6 inches, extending upstream some 10 to 15 feet, depending upon the size of the 

spill.

Sorbents other than straw may be used; however, make sure that sufficient material is used to 

ensure some sorbent depth at the dam. Whereas straw readily gives a desired depth, some other 

sorbents tend to float permanently and additional material is needed to achieve the proper sorbent 

depth at the barrier.

Figure 7-15 : Cross Section of a Sorbent Fence

Weights on the bottom of the wire mesh keep it from planing and releasing the sorbent and 

oil.

The effectiveness of this type of barrier depends on the amount of water in the stream and its 

velocity, size of the spill, and physical characteristics of the oil. Runoff from a large rain may 

well cause dam failure. Under normal conditions, a sorbent dam should withstand water
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velocities of up to 2 feet to 2-1/2 feet per second. The type of oil spilled will determine how 

much sorbent material will be needed. The lighter the oil, the more absorbent that will be needed. 

Therefore, second and even third absorbent dams may be necessary to recover all the spilled oil.

7.4 COLLECTING AGENTS

Under favorable conditions, certain oil spills can be contained temporarily with chemicals. When 

applied to the surface, these chemicals will retard the spreading oil and may even concentrate the 

spill. Wind, waves, rain, and currents may hamper the use of these collecting agents and, 

therefore, must be considered when contemplating the use of collecting agents.

The CI Agent product, as introduced in Section 6.5.2—in loose powder form or in the form of 

marine booms, pads, and pillows—can be used to immediately control emergency hydrocarbon 

spills, to immobilize the petroleum-based material on either fresh or salt water. In loose form, CI 

Agent can be broadcasted manually or with mechanical assistance. Obviously, the choice of the 

immobilization method will depend on the nature and size of the spill, and the surrounding 

ambient conditions, downstream environment considerations, and disposal product reclamation 

options.

CI Agent can also be used in its many forms on lakes and ponds whenever the public, marine 

life, or other wildlife is threatened, or when the spill is heading toward flowing waters. Again, 

the nature and size of the spill determines the method of use. In loose form, CI Agent can be 

broadcast over the entire area and once the spill is solidified, holes can then be cut into the mass, 

so as to allow the lake or pond to breathe to save the marine life. Retrieval of the encapsulated 

material from the water can then take place by skimming or vacuuming.
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CHAPTER 8

OIL REMOVAL MATERIALS

8.1 SORBENTS

“Sorbent” is the term given to those products or materials that are oleophilic—oil-attracting—

and hydrophobic—water repellent. That is, they have a high capacity for adsorbing or absorbing 

an oil product, and they tend to repel water. In usable form, sorbents must float on water long 

enough to adequately collect the oil and then be removed.

Definitions of sorbents provided by the American Society for Testing and Materials include:

Adsorbent—An insoluble material that is coated by a liquid on its surface, including 

pores and capillaries, without the solid swelling more than 50 percent in excess liquid

An incomplete list of adsorbent materials used on oil releases includes plastic fibers such 

as polypropylene, plastic foams, straw, peat, sand, feathers, foamed glass and silicates, 

activated alumina, and soil.

Absorbent—A material that picks up and retains a liquid distributed throughout its 

molecular structure, causing the solid to swell—50 percent or more. The absorbent must 

be at least 70 percent insoluble in excess fluid.

Absorbent materials for organic liquid releases include rubbers and cross-linked products 

such as imbibing polymers.

Sorbents can be classified as either mineral products, natural (organic or agricultural) products, 

or manufactured (synthetic) products.

Sorbents are used widely to clean up small terrestrial or marine spills and for completing the 

cleanup of a large spill. Their use is generally more costly than conventional mechanical 

procedures except for small, or thin-layer oil spills. Sorbents usually have to be spread and 

recovered by hand, thus limiting the area that can be adequately cleaned by this process. 

Selection of sorbent materials for storage and use will be influenced by the local exposure to oil 

spills and the type of hydrocarbon that might be spilled. The following may assist in this 

selection.

8.2 MINERAL PRODUCTS

Several commercially available minerals have a high affinity for oil, including volcanic ash, 

diatomaceous earth, vermiculite, perlite, and some chalks. For oil spill cleanup work, these 

materials need to be ground into a very fine-grain form. This leaves much of the material as dust, 

one of its greatest disadvantages. The materials do adsorb certain oils to acceptable ratios—three 

to six times their weight—but are very expensive and thus are not commonly used for oil-onwater cleanup. Also, the oil spill recovery process may be complicated because these materials 

may:
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• Be too fine-grain to permit removal by conventional means such as nets and sieves

• Be abrasive to mechanical pumps

• Require specialized equipment to spread and recover

• Not burn, eliminating burning as a disposal process.

8.2.1 Natural or Agricultural Products

Many agricultural products are available for use in adsorbing oil from water. Most leaf-like 

plants contain some natural oils, giving them a greater affinity for oil than water. When dry, they 

are lightweight enough to float on water. All of these products will become water-wet and sink, 

carrying the oil with them. Straws with hollow stems will float for longer periods than grass or 

hay. These sorbents are plentiful in agricultural communities and usually are available within a 

short distance.

Agricultural products are relatively inexpensive but are bulky. If needed in sizable quantities, 

they will require large protected storage areas. Rain-wet straw or hay loses a great deal of its 

affinity for oil, is more difficult to spread, and will sink more readily. The method of packaging 

or baling is important. Baling wire will quickly rust out in humid climates, rendering the bale 

useless for transport. Plastic baling line for storage of hay or straw is preferable.

Spreading an agricultural product on the water or along a beach can be a costly and timeconsuming operation unless a mechanical spreader can be used. Such mechanical units usually 

are available in agricultural communities and also are used by highway construction contractors.

Some of the natural products that have been tested and used as oil spill sorbents include

• Rice straw

• Oat straw

• Wheat straw

• Flax straw

• Johnson grass (hay)

• Coastal Bermuda (hay)

• Bagasse (sugar cane)

• Buffel grass (hay)

• Red top cane

• Cottonseed hulls

• Corn cobs (ground or unground)

• Peat moss

• Sawdust

Straws are the most common and widely used natural sorbent materials. Straws can be oat, 

wheat, rice, or flax. These are available to most communities. They are the most adsorbent of the 

agricultural products. Straws will float for longer periods because of their hollow or fibrous 

stems. Straw is the least expensive of the natural products and, if baled properly, can be stored 

for many years. Tests have shown that straws have a 30 percent greater oil adsorbing capacity
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than hays, 40 percent more than canes, and 100 percent more than cottonseed hulls. Straws have 

been known to adsorb between 8 times and 30 times their weight in oil.

Grass or hay makes a good sorbent. It is generally available as feed for livestock, but since it is a 

feed, it costs more than straw. This is principally a leafy material that has a high oil-adsorbing 

capacity. However, it can and will become water-wet and sink with the oil. Its use in shore-side 

or beach operations may be justified. It can be removed from the water with fine screens and 

easily raked into piles on a beach.

Bagasse and red top cane are regional products. Bagasse has a high affinity to oil but will readily 

become water-wet and sink. Red top cane, like bagasse, quickly becomes water-wet and sinks. 

Also, it has a relatively low oil sorption capability.

Peat moss is expensive for oil spill cleanup work. Like cottonseed hulls and corncobs, it will 

readily become water-wet and sink. These products can be used on land and on beaches but their 

cost may preclude their use.

Sawdust quickly becomes water-wet, reducing its oil-adsorbing capacity and it tends to sink 

quite readily. Sawdust is also easily churned at the beach by breakers and dispersed in the water 

column, adding to the problem. On the beach, sawdust readily mixes with the sand during raking, 

making it impossible to remove.

8.2.2 Synthetic Products

Synthetic products are widely used and are available from manufacturers under various trade 

names. The adsorbent types are manufactured from high molecular weight polymers such as 

polypropylene, which has higher adsorbing capacities than mineral and cellulosic products. 

Polyurethane, for example, theoretically can adsorb up to 90 percent of its volume. It may in 

some forms collect several times its own weight in oil—more than the mineral or cellulosic 

products. Adsorbents cannot sorb more than their own volume. The viscosity or thickness of the 

liquid being adsorbed will impact upon the adsorption capacity and the amount of oil the 

material will retain on its surfaces. Some of the adsorbed oil can be rereleased from the 

adsorbent during retrieval operations if the viscosity is insufficient to cause the oil to adhere to 

the material’s surfaces. This may impact upon the material’s overall effectiveness for certain oil 

recovery operations.

The absorbent type of synthetic products is also available from manufacturers. These products 

include cross-linked polymers and rubber materials, which absorb liquids into their solid 

structure, causing the sorbent material to swell. It is the swelling of the absorbent that 

distinguishes it from adsorbents. The capacity of absorbents is generally measured in 

volume/volume ratios as the swelling characteristic of absorbents allows these materials to pick 

up many times their volume in spilled liquid. Viscosity also will impact on the effectiveness and 

the absorption capacity. Temperature may impact on the absorption rate, with lower temperatures 

tending to significantly slow the rate. As liquids are integrated into the absorbent material, the 

liquid cannot be rereleased, which virtually eliminates secondary contamination of the 

environment and response personnel.
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The performance characteristics of both absorbents and adsorbents should be considered when 

considering overall cost-effectiveness of a product for cleaning up oil and organic chemical 

spills. Oil types and their viscosities also should be considered, as well as ambient temperatures.

The adsorbent synthetic products are marketed in various forms: (1) as a relatively fine-grain, 

loose, and sugary textured material; (2) as a medium coarse material with particles the size of a 

dime or less; (3) as pads one-quarter inch to one-half inch thick and approximately 12 to 24 

inches square; (4) as particulate baled in pieces the size of a fist; (5) in rolled sheets 3 feet wide 

and 200 feet long; (6) in various pillow-shaped forms; (7) as sorbent booms; (8) as a mop similar 

to a household mop; (9) as a tangled mass of thin strips; and (10) in liquid components for onsite generation of a sorbent foam that can be chopped and spread by hand or by mechanical 

means.

The absorbent synthetic products are marketed in pads, blankets, booms, mini-booms, rolls, and 

socks suitable for groundwater cleanup. One product contains the polymer beads that also are 

used in oil stop drain valves described in Chapter 6. Another product that functions mostly like 

an absorbent product actually chemically reacts with oil to form a rubber type compound. It may 

be an effective alternative in colder weather as absorption time is less affected.

8.2.3 Chemically Modified Natural Product

There is a chemically modified cottonseed lint absorbent. It can sorb two to six times its weight, 

depending on the product. It is at least five times as effective as calcined clay—cat litter—for 

mineral oil. In addition, the product has nutrients to encourage the growth of microbes to “eat” 

the oil. Studies show that, with proper application, this product can bioremediate an area within 

120 days.

8.2.4 Other Products

Other marketed forms will undoubtedly be developed as the need arises, technology advances, 

and research is performed.

8.3 WHEN AND HOW TO USE SORBENTS

The use of sorbents for oil spill cleanup work varies in different areas of the country. Some 

cleanup contractors limit their stockpile to synthetics, while others include agricultural 

products—principally straw.

The following characteristics of sorbents will influence their selection and use:

• Sorption Rate—refers to the speed of absorption or adsorption. The rate of sorption 

will vary with the thickness, or viscosity, of the oil.

o Adsorbent materials are generally more effective with more viscous liquids. The 

thicker oils tend to adhere to the surface of the adsorbent more effectively. While 

adsorbents are generally very fast at adsorbing lighter oils, they also will tend to
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rerelease an amount of these lighter oils just as quickly on retrieval, causing 

secondary contamination.

o The absorption mechanism requires liquids to diffuse into the solid structure of 

the absorbent material. The absorption process is generally faster with lighter oil 

products and slower with heavier oils. Once absorbed, these liquids cannot be 

rereleased. Absorbents are very effective with light hydrocarbons such as 

gasoline, diesel fuel, and benzene, which tend to create problems for adsorbents.

• Oil Retention—Adsorbents will release varying amounts of oil and organic liquids, 

depending on the viscosity of the liquid, during retrieval operations. This is because 

the liquids are held on surfaces either within the adsorbent material, such as pores, 

capillaries or interstices, or on external surfaces of plastic fibers or mineral granules. 

In a stream current in excess of two knots, some oil adhering to adsorbent materials 

will be stripped off by flowing water.

Conversely, the retention of oil by absorbents is absolute. Because the oil has become 

an integral part of the absorbent material’s structure, and not on a surface, the oil 

cannot be removed by stream currents, compression, or gravity.

• All sorbents are bulky; storage of sizeable quantities requires larger, covered storage 

facilities. Straws or agricultural products are the bulkiest and require special storage to 

prevent rodents from nesting and ruining the sorbent.

• In heavy oil exposure areas, stockpiling of sorbents is a must. Having to wait on

delivery of sorbents may be the difference between a minor disaster and a major 

disaster.

• Sorbent products are available in various shapes and sizes. Straw or agricultural 

products come in bales, spread by a mechanical mulcher. Synthetics are available in 

many forms, from sugary granules in bulk to blanket sheets. They are usually spread 

by hand, but mechanical spreading is available for those products made available in a 

particulate form.

• On a per-pound basis, straws are much cheaper to purchase than the synthetics. For 

synthetics, greater sorption ability, the ability of the absorbent type of synthetics to 

permanently retain the absorbed oil, and life cycle cost of use and disposal must be 

considered when selecting synthetic sorbents for storage and immediate availability.

• All sorbents used for oil spill cleanup should be recovered and disposed of through 

standard procedures (See Section 11, Disposal). The small-grained, loose-type 

sorbents are very difficult to remove from water, adding delay and cost to the 

operation.

8.3.1 Application of Straw: Baled straw is a mass of stalks that have been reduced to this state 

by a thorough tumbling in the threshing process. Baled straw is normally used for stock bedding
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because of its toughness and sorbency. In tests, straws—oat, wheat, and rice—have been found 

to collect a large proportion of their ultimate total of oil in the first few minutes after contact with 

oil. Fifty-gram samples of the three straws deployed over a medium gravity crude (Sp. Gr. 0.795) 

for five minutes revealed an average removal of 207 ml. of oil and 8 ml. of water. A 15-hour test 

with the same oil averaged recovery of only 245 ml. of oil and 37 ml. of water. Therefore, straw 

should not be left on water for prolonged periods, as its effectiveness is greatly diminished after 

the first few minutes. As time on water increases, the risk that the oil-soaked straw will sink also 

increases.

Because of its low cost and capability of being mechanically spread over large areas, straw is 

most effective on land, beaches, or shorelines. Land and beaches contaminated with a viscous oil 

that has not penetrated the sand or rocks can be cleansed readily and cheaply using straw. Straw 

also is effective along stretches of shoreline where oil on water is about to reach the shore. Straw 

should be spread plentifully, as it serves a dual role: it collects the oncoming oil and prevents or 

reduces the amount of oil that reaches the beach itself. Under these circumstances, the amount of 

straw spread, time on water, and removal should be carefully controlled.

Straw also will make a very effective dam either in baled form across shallow water or in 

dispersed form behind a wire fence in deeper water (Figures 8-1 and 8-2).

Straw spread over water will consist of many small pieces of stalk. These small pieces will find 

their way into places difficult to reach for removal. Therefore, try not to use straw as an oil 

sorbent near an open rocky shoreline where it cannot readily be removed.

Straw on open waters is difficult to retrieve. Special recovery sieves are needed and, even then, 

all of it will not be recovered. Open water spreading of straw should be avoided unless the spill 

is small, contained, and mechanical means are not available to remove the oil.

Spreading the straw on an oil spill on water precludes the pumpability of the oil, rendering 

mechanical removal devices useless. Therefore, do not spread straw on an oil spill that can be 

removed more effectively by pumps or vacuum units.
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Figure 8-1: Straw Skimmer

Stretch wire fence across stream and anchor securely. Straw is placed on upstream side of 

fence. This type of installation should be used where the stream banks are of sufficient 

height and movement of water is relatively slow.

Figure 8-2: Straw Skimming Installation

The ordinary straw skimmer may not be used effectively in a stream having a constantly 

changing flow direction. When this type of skimmer is installed in a body of water that is 

subject to fluctuating flow movement, the straw must be held in place by wire fence on both 

sides of it.
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8.3.2 Using Synthetics: Synthetic sorbents play an important role in recovering oil. Besides 

being used by oil spill cleanup contractors, they are widely used to remove oils from such areas 

as floors of factories, machine shops, and electrical oil filter equipment. All oil spill cleanup 

contractors stock large supplies because synthetic sorbents serve a vital need. These products are 

more expensive than straws but work well in certain situations where the straws should not be 

used. Like the straws, synthetic sorbents would not be economical or efficient to use where 

mechanical—pump or vacuum—removal of the spill is possible.

Synthetic sorbents can be divided into five categories:

8.3.2.1 Fine to Medium Grain: In this form, the product is difficult if not impossible to remove 

from water. It should not be used for retrieving oil from water unless marketed in a form—pad, 

boom, etc.—that is specifically approved for use on water. Fine grain sorbents are best used to 

clean up oil from terrain and to sorb oil out of oil-soaked lawns. The fine grain particles should 

not be used on beaches, as raking will only mix the oil-soaked sorbent with the sand, adding to 

the removal problem. This type of product should be stocked in those isolated areas that are 

exposed to oil spills that may trespass private lawns, golf courses, etc.

8.3.2.2 Coarse Grain (Particulate): This versatile sorbent can be deployed by hand or machine. 

The pieces are large enough to be easily removed by rakes or sieves from beaches, water, or 

terrestrial areas. Because of its relatively high cost, its use should be limited to the cleanup of 

small spills that other sorbents or mechanical units cannot remove more rapidly and at less 

expense. Using particulate in open rocky areas is not advisable, as the pieces are not connected 

and, therefore, could be difficult to remove.

8.3.2.3 Pads: These types of sorbents are marketed in cartons or bundles weighing 15 to 25 

pounds and containing 100 to 110 pads, each approximately 12 to 24 inches square and between 

one-quarter and one-half inch thick. These pads are the most commonly used of all the synthetic 

products. Some have grommets in one corner so that they can be connected for isolating in a 

specific area and for quicker removal. The pads must be manually deployed, and usually are 

recovered by hand. They are commonly used to clean up small spills or to polish the cleanup of 

larger spills. The pads containing true absorbent polymers are especially effective for final 

cleaning and polishing in most cases. These pads can be used effectively for absorbing oil out of 

rocky crevices and hard-to-reach places. They become entirely impregnated with oil when spread 

on a thick layer of medium to light gravity oils. When the spilled oil is thin—such as insulating 

oil—only one face of the pad and its perimeter get oil-wet, requiring manual turnover. Pads are 

not effective in sorbing a viscous material from the water or a beach.

Some types of pads are fibrous, which permits wringing out the oil and reusing the pad. This is 

not recommended or commonly done because the labor cost of wringing the pad exceeds the 

initial cost of the pad. There is also danger of personnel contamination or of reintroducing 

contamination into the environment. However, if a temporary shortage should exist, then 

wringing could be justified.

8.3.2.4 Rolls: Rolls have a more limited use but offer some advantages. Since the sorbent 

material is in a rolled form, it is more concentrated, thus requiring less storage space for equal
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poundage. Rolls can be used on a beach by spreading out the entire roll at the water’s edge to 

receive an oncoming light gravity oil spill—such as diesel fuel or insulating oil. This is one case 

where using sorbent rolls is preferable to using straws. The rolls also can be used as footpaths for 

personnel and wheelbarrows or as blankets for temporary storage of oil-soaked material to 

prevent dripping oil from recontaminating clean areas of beaches, docks, etc. Pieces can be cut 

from the rolls when sections larger than the pads are needed. Storing some rolls of sorbents in 

areas of high oil spill exposure may well be worthwhile.

8.3.2.5 Other Forms: Synthetic adsorbent or absorbent material is also marketed as pillows and 

booms, and adsorbents as a mass of thin strips, much like strips of cellophane. The pillows can 

resemble house pillows and are covered by burlap or other porous material of various shapes. 

Some pillows are grommeted for joining for easier use and recovery. Sorbent pillows can be used 

to plug leaking boom sections, to recover oil in rocky areas, and to make booms by tying 

together several pillows.

Sorbent booms are available, manufactured much like the pillows but longer, in 20- to 25-foot 

sections. They do not have a skirt or tension member and should only be used to sorb thin, light 

gravity oil films along a relatively short distance. Sorbent booms are relatively expensive and 

cannot be reused, so their use can be justified only for isolated and special incidents. This type of 

sorbent would work best across a slow-moving, narrow body of water with a widespread, thin 

film of high gravity oil.

Synthetic sorbents also are available in thin strips of vitreous material that can be tangled to form 

a loose mass or paralleled and tied to a pole to form a mop, much like a household mop. The 

tangled mass can be thrown into a viscous spill, allowed to sorb the oil, then be removed 

manually or by a specially designed mechanical apparatus. This method of removal is effective 

on viscous oil at shoreline locations where a considerable amount of debris is present. However, 

before employing this method, compare its cost with the cost of first removing the debris and 

then removing the oil by other means. When the tangled mass type is used, it usually is discarded 

after recovery, since the labor cost of squeezing the oil from the base, loosening the fibers, and 

redeploying will exceed the cost of a new unit.

The mop types are used manually for removing a spill from difficult-to-reach places such as 

crevices, rocky areas, between floating craft, under confined piers, or dock facilities. 

Consideration should be given to an alternative absorbent type of product that may provide a 

more complete removal of many oils if a pad type product is practical to use.

8.4 BIOLOGICAL DEGRADATION

The waters of the United States contain many species of microorganisms, which increase in 

abundance between colder waters and warmer waters. These microorganisms consume 

hydrocarbons (oil) as an energy source. The natural microorganism process of consuming and 

thereby removing oil from water is well recognized and is the reason given for the disappearance 

of much oil spilled in the waters throughout the world. However, the use of the process as a 

practical method of removing oil from inland or coastal waters is questionable.
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Detergents and dispersants can be used to break up an oil spill into smaller oil droplets, 

permitting more rapid decomposition of the oil by microbial action. The ecological effects of this 

use are debated among marine biologists. Some of these biologists advocate the use of chemicals 

to disperse the oil in waterways, while others are opposed to the use of either detergents or 

dispersants under any circumstances, claiming the oil and chemicals form a more toxic mixture.

The natural microorganism process alone does remove some oil spilled on the waters, but it 

should not be expected to materially assist the overall spill cleanup problem other than as a 

bonus in the cleanup of any residual oil.

8.5 COMBUSTION

This method of oil-on-water removal is effective where the conditions and regulations permit. 

Combustion is the most inexpensive way to remove oil, but it also is the most hazardous. Many 

factors should be considered when contemplating burning oil floating on water, including:

8.5.1 Ignition

It is nearly impossible to ignite a thin layer of low-gravity oil floating on a large body of cold 

water because of conductive heat losses into the water. If oil is lighted, steam is generated, which 

chokes off oxygen and smothers the flame. Burning is not a complete process; therefore, other 

methods are required to remove the residual oil.

Several manufacturers are demonstrating so-called “wicking” agents, which act much like a wax 

candle. When spread on oil and set afire, heat from the burning wick reduces the viscosity of the 

surrounding oil, which then is drawn into the burning area. The wicks insulate the water from 

much of the heat combustion. These “wicking” agents are bead-like and some can be recovered 

and reused. The cost of the “wicking” agent, the equipment to spread and recover it after 

burning, and the cost of cleaning and restoration must be considered in estimating the overall 

cost of cleaning up an oil spill by the combustion process.

Generally, the longer the spilled oil remains on the water, the more difficult it is to ignite and 

burn, primarily because the volatile components—which are most easily burned—evaporate 

quickly. This method of removing spilled oil from water offers some limited use but, in general, 

is not operationally practicable.

8.5.2 Smoke

Permits from air pollution agencies are required to burn oil off water because the poor 

combustion causes heavy smoke. Keeping a contained oil spill burning will consume the 

containing equipment, unless earthen or fireproof devices are used. This special equipment will 

greatly increase the associated cost of containment. Burning of oil spills in or near public or 

private structures should never be considered.
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8.5.3 Wind and Wave Action

Wind and wave action has a cooling effect through convection and adds greatly to the loss of 

heat.

8.6 SINKING AGENTS

Warning: The use of agents to sink the oil should never be used, since this method is irretrievable 

and illegal in U.S. waters.

This is a process of removing an oil slick from the surface of water by simply spreading a 

hydrophobic material over the oil that becomes coated with oil then sinks in the water. The 

process is not accepted. The mechanism of sinking and the depth to which the oil-coated material 

will sink are not fully known yet. These factors vary with the properties of the oil, water, and the 

material used, as well as prevailing climatic conditions. The oil retentive quality of the material 

used also can vary with time and changes in climatic conditions. This may then result in release 

of the attached oil, permitting it to resurface.

The effects of this method are toxic to the environment. Wildlife regulatory agencies are opposed 

to the use of sinking agents because this method transfers oil from the surface of the water to a 

depth where it may be even more harmful to the ecology of the area. The use of this method also 

would be relatively ineffective and too costly to use on a thin oil slick.
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CHAPTER 9

OIL REMOVAL ON WATER

9.1 OIL REMOVAL METHODS

Once an oil spill on water has been contained by any of the means described in the containment 

section above, it must then be removed using the most effective method—one that has the lowest 

cost and causes the least harm to the ecology of the area.

Like containment, removal of an oil spill from the surface of the water can be a complex task 

requiring a variety of methods. Mechanical units such as skimmers or vacuum trucks may be 

used. In some spills, the use of sorbent materials to soak up the oil may suffice. Even nature can 

play a role through the process of bacterial degradation. Under special conditions, chemicals may 

be used to disperse the spill in the water column. Finally, the oil spill may be removed by 

burning it off or by spreading heavier-than-water granules on it and sinking the oil to the bottom. 

(Note: U.S. regulations prohibit the use of sinking agents.)

See Chapter 8 for a description of sorbents, chemical, and biological processes, and other 

nonmechanical methods of oil removal. Mechanical methods of oil removal are discussed in the 

rest of this chapter.

9.2 VACUUM UNITS

Using a vacuum unit is one of the most acceptable methods for removing a contained oil spill, 

unless the spilled hydrocarbon is too viscous to be sucked into the unit. A vacuum unit on a truck 

bed combines the spill removal and transportation functions, saving several steps that would 

otherwise need to be taken without such a unit. This contributes to lower cleanup costs.

Although the vacuum truck is one of the most commonly used tools in the oil spill cleanup 

business, it does have some disadvantages that should be considered.

• It is a large, expensive, mechanically complicated unit

• The size and weight preclude accessibility to many oil spill areas

• Proper maintenance is mandatory and is expensive if the truck is not used regularly

A small, skid-mounted vacuum unit may serve well in an area where small oil spills 

predominate. This kind of unit can be mounted on a trailer for transporting it to a spill site. A 

skid-mounted unit can be towed along a beach by a tractor. Such a unit usually can be designed 

for the needs of an area and built by the nearest tank or welding shop.

Vacuum units are most effective when a spill has been contained in thick pockets of relatively 

pure oil. Because of the high per-hour cost of operating vacuum units, their use will not be the 

most cost-effective method of removing small, or widely dispersed, thin layer oil spills. 

Additionally, large amounts of debris can clog hoses and pumps. In such a case, prescreening of 

the debris is required (See Figure 9-1).
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Figure 9-1: Tank Truck

The oil-water mixture is pumped into the top of the tank and, after separation of oil and 

water, the water may be returned to the stream by opening a valve at the bottom of the 

tank and running the water through an oil sorbent filter medium to remove most traces of 

residual oil. Certain synthetic oil sorbent filter designs are commercially available for this 

purpose. Sufficient settling time should be allowed to permit a fairly complete separation.

9.3 SKIMMERS

Many mechanical devices have been developed to receive and physically remove spilled oil from 

the surface of a water body. These devices are called skimmers. They vary in shape, size, 

purpose, and cost. Skimmers may be simple homemade units made from scrap parts costing 

little, to sophisticated, complex units priced at several hundred thousand dollars each.

The two basic types of skimmers used today are:

• Suction units

• Oleophilic units

Although suction units vary greatly in design and purpose, they all require some sort of suction 

device to remove the entrapped or contained oil. The above basic units may be subdivided into 

five categories:

• Enlarged suction head

• Floating weir

• Oil-water trap

• Dynamic inclined plane

• Cyclone operation
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Oleophilic units use a material to which floating oil will adhere. The oil is removed from the 

material by various systems. Several types of oleophilic materials and removal systems are used 

in this skimmer category, which may be subdivided into:

• Belts

• Drums

• Disks

• Ropes

Unfortunately, there is little versatility in skimmer design and purpose and there is a fairly rigid 

set of conditions under which skimmers will operate properly. All have varying difficulty with 

wave action. Some are extremely sensitive to air intake and the subsequent loss of suction and 

most cannot be used in debris-laden waters.

Generally, an oil skimmer should meet these criteria:

• Be quickly deployable during worse-than-average climatic conditions

• Be able to handle small solids and debris without damage

• Use self-priming and/or diaphragm type pumps

• Be rugged and dependable for continued operation with minimum maintenance

• Be able to operate in shallow waters (10 in. to 20 in.)

• Be as portable as possible

9.3.1 Suction Types

9.3.1.1 Enlarged Suction Head Skimmers: Enlarging the head attached to the end of a suction 

hose increases horizontally the area over which suction is exerted. Such a head floats on the 

water with the suction opening at the oil-water interface. See Figure 9-2 for three different types 

of such heads.

Figure 9-2: Three Types of Enlarged Suction Heads

(A) Duckbill, (B) Pipe Extension, (C) Flexible
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A flexible head is more versatile than a rigid type, as it will contour itself to small wave action, 

maintaining its effectiveness. The capacity of a unit will depend on the size of the head, size of 

the suction hose, and pump capacity. A delicate blending of all three factors is needed for 

effective results.

These units will operate in shallow water, but they are subject to being clogged by debris. They 

also can draw air, which will impede operations unless self-priming pumps or vacuum units are 

used. Care should be taken when deploying the units in choppy or debris-laden waters. These are 

relatively low-cost skimming units.

9.3.1.2 Floating Weir Skimmers: Floating weir skimmers are mechanical devices that float on 

water and permit oncoming oil to pass over its adjustable weir plate onto an area where the oil is 

confined and then sucked or pumped off. The units are widely used and are available in a variety 

of shapes, sizes, and capacities. Figure 9-3 illustrates the weir skimmer action.

Figure 9-3: Weir Skimmer Operation

These units, like the suction head skimmer, are portable and can be deployed quickly. The cost 

of such units is supportable when compared to that of the large units requiring service crews and 

craft. They can be located in the center or near center of a contained spill or maneuvered about in 

the contained area by ropes handled by two persons.

The capacities of floating weir skimmers depend on the sump size of the weir, size of suction 

hose, and capacity of the pump. The units are very effective in medium- to light-gravity oil spills 

where the water is quiet and debris-free. The units are generally light in weight and buoyant, 

which makes them susceptible to failure in medium choppy water. They can be clogged quickly 

in debris-laden waters and will usually require personnel to adjust the weir or unclog the screen.

Using a weir skimmer requires practice and experience to be most effective. Weir adjustments, 

relocation, and cleaning of debris usually require constant attention from the crew, all of which 

adds to the cost of the operation. The use of such units should be limited to those times when 

other types of spill removal are not justified.
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9.3.2 Oleophilic Types: These types operate on the principle that oil rather than water will 

adhere to the oleophilic part of the unit, which is immersed in the oil. As the part is mechanically

removed from the spill, the adhering oil is either wiped, scraped, or squeezed off into recovery 

tanks. Metal and plastic surfaces are used for the oleophilic parts. These skimmer types come in 

various forms and shapes.

Any piece of rope dragged through an oil spill will adsorb some oil. The larger the rope or the 

greater the surface area exposed to the spilled oil, the greater the removal. Also, the more 

oleophilic the rope material, the more oil and less water that will be removed.

One manufacturer has applied this principle and markets a rope type skimmer. This unit is 

widely used and is available with assorted sizes and lengths of rope. The rope consists of a basic 

tension core to which is interwoven additional oleophilic material to enlarge the overall diameter 

and increase many-fold the surface area that is exposed to a spill. These ropes are available in 

sizes with outside diameters ranging from 4 inches to 36 inches and can be provided in any 

length.

The rope is deployed into an oil spill as a continuous loop, moored at one end around an 

anchored, floating, tail pulley. The oil adheres to the rope and is removed by a wringer as it 

passes through a power machine located at the opposite end of the rope extension. The power 

units that propel and wring the rope are available in a variety of sizes and can be driven by 

gasoline, electric, diesel, or pneumatic engines.

This type of skimmer is effective and versatile. It recovers little free water, will operate in light 

or viscous oils, and is not too troubled by debris. The units are operable in shallow or deep 

waters, wherever the trail pulley can be stationed. Portability allows for reasonable response 

within a limited area. The main disadvantages are rope maintenance and relocation costs. Care 

has to be taken to prevent recontamination from dripping oil as the rope approaches the unit. 

Other sorbent materials on the water, dock, or ground around the power unit may be needed for 

this protection.
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CHAPTER 10

OIL SPILLS ON LAND

10.1 MIGRATION OF PETROLEUM PRODUCTS IN SOIL AND GROUNDWATER

Petroleum oil spills on land are a concern for the electric industry since the majority of facilities 

do not spill oil directly into waterways but, rather, will migrate oil into groundwater sources. The 

actual impact of land spills will vary widely and will depend on such factors as volume of spill, 

type of soil, nature of groundwater system, and the weather. It is, thus, nearly impossible to 

outline procedures that are universally applicable for all circumstances. The mechanisms of 

migration are complex, but where sufficient geological data are available, it is possible to predict 

whether a given amount of oil is likely to reach a water table or to estimate the depth to which it 

is likely to migrate in the soil. When a large amount of oil is involved, skilled geological and 

hydrological personnel may be helpful in determining problem areas.

In order to have a better understanding of the potential hazard of oil on water supplies and/or 

groundwater, a discussion of soil characteristics and water hydrology is necessary.

To anticipate effectively the behavior of oil spilled on soil requires detailed knowledge of the 

local geology and groundwater conditions and of the principles described here. The geology of 

most areas of the United States has been mapped quite thoroughly and groundwater conditions, 

where they are important, are well understood. Leading sources of such information include:

• United States Geological Survey, Groundwater Division (offices in most major cities and 

State capitals)

• State water resource agencies (described by various titles)

• State Geological Surveys (usually in the State capital, but often associated with a State 

university)

• University geology departments

• City water departments

10.2 ROCKS AND SOIL

Most rocks and soils are composed of small fragments or grains such as sand. The irregular 

shape of these grains, when they are pressed together, creates small openings or voids. A 

quantitative measure of the total column of the voids is the porosity of the rock or soil. It is 

within these pores that fluid may be contained. If the pores are interconnected, the rock is 

permeable; that is, a fluid can pass through it. Permeability is a quantitative measure of this 

property. Materials such as clay, silt, and shale are called impermeable because they have 

extremely small pores, are poorly interconnected, and fluids cannot pass readily through them.

The more common rocks and soils are sedimentary. Usually they occur in distinct layers or beds 

as a result of successive deposition of different types of rock material. Such bedding is 

commonly exposed in road cuts. The beds may be horizontal, but more often will slope or “dip” 

in some direction. This dip, in addition to the varying porosity and permeability of the different 

layers, does much to govern the movement of fluids underground.
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One particular rock, limestone, is especially soluble in water. Limestone that is near the surface 

sometimes develops large openings and fissures that range from less than an inch to many feet 

across. The more spectacular examples include great caverns such as Mammoth Cave in 

Kentucky and Carlsbad Caverns in New Mexico. The rock in such caverns clearly has extremely 

high porosity and permeability. In other instances, limestone may have very low porosity and 

permeability.

Crystalline rocks, such as granite, marble, and quartzite, usually are not porous. Frequently, 

however, such rocks are cracked or fractured to some depth, and a certain amount of fluid may 

exist in and move through these openings.

10.3 GROUNDWATER

In most parts of the United States, free water exists at some depth in the ground. In many areas, 

enough is present to provide a major part of the water supply for towns and cities, as well as rural 

areas. In areas where groundwater is used extensively, products spilled on the ground may create 

risk of contamination.

The source of most groundwater is precipitation over land, where water is adsorbed by porous 

soils and rocks at the surface. Other important sources are rivers and streams that may lose water 

into the subsurface. Details of a hypothetical total groundwater system are shown in Figure 10-1.

Moisture is present to some degree in practically all soils. Starting at the surface, moisture 

generally increases with depth in a zone of partial saturation called the vadose zone. The depth at 

which water completely fills the pores in the soil defines the beginning of the zone of saturation. 

The upper surface of this zone is the water table, and the water in the zone is groundwater.

The position of the water table is revealed by the level to which water rises in wells. The water 

table usually is an undulating surface that conforms in a general way to the topography of the 

land. It fluctuates seasonally, rising during rainy seasons and falling during dry periods. 

Immediately above the water table is the capillary zone. This zone may vary in thickness from 

less than an inch in coarse, permeable soil to 15 inches or more in very fine-grained, lowpermeability soil or rock. Water in the capillary zone will not flow, since it is held by capillary 

forces that are stronger than gravity. The capillary zone is important because its nature and 

thickness determine the spreading characteristics of oil that reaches the water table.
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Figure 10-1: Hypothetical Groundwater System

Most layers of rock or soil in a groundwater system can be classified as either aquifers or 

aquicludes. An aquifer is a layer of rock that is sufficiently permeable to transmit water in usable 

quantities to a well or spring. An aquiclude, on the other hand, is sufficiently impermeable to bar

the passage of water. An aquifer where the water table is not separated from the surface by an 

aquiclude is an “unconfined” aquifer, and groundwater associated with it is free to move by 

gravitational forces. An aquifer that is overlaid by an aquiclude is a confined or artesian aquifer. 

Artesian water normally is not free to move by gravitational forces, but is under sufficient 

pressure to rise above the top of the aquifer in a well or spring. The height to which artesian 

water rises at such a discharge point is a measure of the pressure head created by the weight of 

the water in areas of the aquifer at higher elevation.

In certain situations, a body of groundwater may be hydrostatic in that, essentially, it does not 

move. In most cases, however, groundwater is constantly in motion. Water in an unconfined 

reservoir is under atmospheric pressure and moves laterally under the influence of gravity toward 

a point of discharge such as a well or spring. The direction of flow will, as a rule, roughly 

parallel the land surface. Water in an artesian aquifer is under a pressure related to the highest 

elevation of the aquifer and will move toward the point of lowest pressure. This point may be a 

well or, more commonly, an area where the overlying aquiclude is locally super-impermeable 

and permits slow upward leakage into higher beds. So long as the system remains artesian, the 

rate of leakage cannot exceed the rate at which new water is entering the aquifer at a higher 

elevation.

Certain cities and industrial areas draw many millions of gallons daily from groundwater 

reservoirs. The sites and relative production rates of the wells can disrupt normal flow patterns 

significantly. Complete reversal of direction in limited areas is not uncommon. In such areas, 

fortunately, considerable data are usually available for use in solving groundwater problems. In 

complex situations, the direction of flow is determined by drawing maps based on pressure data 

from wells in the area.
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The rate of movement of groundwater is usually overestimated by most people, who think of it in 

terms of a surface stream. A more realistic comparison is the flow in a large lake where water 

moves imperceptibly toward a single outlet. Measured rates of groundwater movement vary 

markedly, from many feet per day to a few feet per year. The range is so great that the data are of 

little use in terms of specific locations. The water in a typical sand aquifer might move from 

several inches to 4 or 5 feet per day. The rate in a limestone or gravel aquifer could be much 

higher. The rate of flow depends mainly on the permeability of the aquifer and the hydraulic 

gradient or slope of the water table. To measure the flow rate of groundwater directly is 

extremely difficult and is seldom used in practice. Such data, when required, usually are 

calculated by hydrologists using permeability and pressure data from wells and cores of the 

aquifer or from actual pump tests.

10.4 BEHAVIOR OF SPILLED OIL IN SOIL

An accidental spill of oil or its products may occur suddenly or it may occur slowly over a long 

period. The physical behavior of the spilled material is the same in each case, varying only in 

time and extent. A slow leak over an extended period is not detected until oil appears at some

point where it is not wanted. By then, the problem of controlling the spill may be very difficult 

and expensive.

Spilled oil commonly migrates along artificial fills, such as pipeline trenches, foundation fills, 

and utility conduits, in a manner somewhat related to its behavior in natural soils. Such 

excavations often are backfilled with material more permeable than that removed. These 

excavations consequently offer a migration route of minimum resistance, and any fluid will tend 

to move along them more rapidly than through natural soils.

Oil spilled on undisturbed ground will tend simply to move downward, under the force of 

gravity, while spreading laterally to some degree. The rate of movement depends on the viscosity 

of the oil and permeability of the soil. If the spill area is essentially round, the general shape of 

the area of passage is a cone, modified by the nature of the soil layers the oil passes through 

(Figure 10-2). The downward movement eventually will be interrupted by one of three events: 

the oil will be exhausted to immobility, it will encounter an impermeable bed, or it will reach the 

water table.

10.4.1 Exhaustion to Immobility

As the oil moves downward through the soil, a small amount attaches itself to each particle of 

soil contacted and remains behind the main body of oil. Where the spill is small relative to the 

surface area available for contact in the zone of migration, the body of oil is exhausted on the 

way down until the degree to which it saturates the soil reaches a relatively low point called the 

“immobile” or “residual” saturation. At this point, the oil essentially stops moving. If the 

condition develops before the oil reaches the water table, the danger of further contamination is 

greatly reduced. Subsequent rainfall percolating through the soil will carry minor additional 

amounts of residual oil and dissolved components downward. This situation, however, creates 

less risk of significant pollution than if the main body of oil reaches the watertable.
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Figure 10-2: Generalized Shapes of Spreading Cones at Immobile Saturation

At the time of a spill, precise and detailed data on the nature of the soil and oil are rarely 

available. Should they be available, however, the volume of soil required to immobilize the spill 

can be calculated using the following (saturation) equation:

8.4 x V = Cubic yards of soil required to 

P x Sr attain immobile saturation

Where: V = volume of oil in gallons 

P = porosity of soil

Sr = residual saturation = 0.1 for light oils

If the depth of the water table is known, the saturation equation can be used to estimate the 

likelihood that the spilled oil will reach it. To do so, calculate the volume of soil that lies under 

the surface area of the spill to the depth of the water table. Make little or no allowance for the 

lateral spread of oil underground. The result will conservatively understate the volume of soil 

actually available to sorb the oil. If the result, in cubic yards, is less than the value obtained from 

the saturation equation, a risk exists that fluid oil will reach the water table.

10.4.2 Movement to Impermeable Bed

As the body of spilled oil moves downward, its course is affected by the variations in 

permeability of the various soil layers through which it passes. Should the oil encounter an 

impermeable layer, it will spread laterally until it reaches immobile saturation or until it comes to 

the surface where the layer outcrops. Should the latter occur and enough oil is still in motion, a 

second cycle of soil contamination will begin (Figure 10-3). These events can occur only if no 

effective water table exists above the impermeable bed. The condition is most common in an arid 

region or during a dry season and, as a rule, only exists within several feet of the surface.
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Figure 10-3: Demonstration of Possible Migration to Outcrop, Followed by Second Cycle of 

Groundwater Contamination

10.4.3 Movement to Groundwater

The movement of oil downward to contact the water table usually is the most hazardous possible 

result of a spill on land. The degree of risk depends on the nature of the groundwater system and 

the extent to which it is used.

In the capillary zone, immediately above the water table, the water content begins to increase, 

reaching 100 percent at the water table. In very fine-grained sediments, the capillary zone may 

be 15 to 18 inches thick; in coarse-grained material, 1 to 3 inches is common. As the descending 

body of oil reaches the top of the capillary zone, the oil begins to spread over the water table. It 

spreads in a layer roughly the thickness of the capillary zone and elongated in the direction of the 

water’s movement. The oil continues to move, forming a pancake-shaped layer until it reaches 

immobile saturation or returns to the surface at a discharge point (Figure 10-4). The ultimate 

extent of the oil pancake can be calculated, but doing so under field conditions involves so many 

assumptions and estimates that the result can easily be inaccurate by more than 100 percent. In 

practice, such calculations must be treated with great discretion. The transport of oil in moving 

groundwater is governed by complicated mechanisms for which exact explanations are neither 

possible nor necessary. A few basic facts suffice for practical understanding. Most oils do not 

mix with water, but simply float on its surface. However, some refined products contain 

components that are soluble or will diffuse in water to the point where they become offensive 

and make the water unfit for domestic use. As a rule, the lighter the product, the greater it’s 

content of soluble or diffusible components. These general principles are illustrated in 

Figure 10-4.
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Figure 10-4: Movement to Groundwater

Most of the oil that reaches a water table will be suspended or will float at or near the surface of 

the water. The oil will tend to move with the water, but it will be adsorbed continually by soil 

particles that it contacts. Thus, the volume of oil being transported will shrink eventually to zero. 

If the water table drops, the oil will follow and some of it will be adsorbed by the soil it passes 

through. When the water table rises, oil previously adsorbed by the soil will be picked up and 

will continue to move laterally with the groundwater (Figure 10-5).

Groundwater is recharged most commonly by rainfall that infiltrates the soil and percolates 

downward to the water. Where this water passes through the cone of residual oil, or through the 

pancake of oil of the water table, it will pick up soluble components of the oil and carry them 

into the groundwater system. Experiments have shown that some of these dissolved components 

may be adsorbed by some types of soil through which the groundwater passes. Later, when 

weaker solutions of the dissolved components enter the same part of the soil formation, they may 

redissolve the adsorbed components. The net result of these processes is that oil dissolved in 

groundwater will tend to travel at a lower velocity than the water and thus to persist longer in a 

given area.
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Figure 10-5: Contaminating Effect on Soil Caused by Vertical Movement of Oil on 

Fluctuating Water Table

10.5 LAND SPILL CONTROL AND RECOVERY

Two steps must be taken following an oil spill on land: immediate measures, which are to be 

implemented after the spill to minimize seepage; and restorative measures, which are concerned 

with recovery of oil after seepage has occurred. The methods described in this section can be 

used at an early stage for either step. More complicated and exotic methods may sometimes be 

required.

Immediate measures apply to spills that are detected soon after they occur. Oil spreads into the 

soil fastest immediately after the spill and the rate diminishes rapidly with time. For maximum 

effect, measures to recover fluid oil at the surface must be taken as soon as possible. Oil may 

seep into clay soils quite slowly, allowing several hours or even days for surface recovery.

A sandy, gravelly soil, on the other hand, may adsorb the oil in a few minutes. (See soils section 

in Chapter 6.) The main limitation to surface recovery will be the time required to mobilize 

suitable equipment and supplies.

If conditions favor an attempt at surface recovery, three basic techniques should be considered: 

containment, surface spreading, and absorption. The selection will depend on the volume of the 

spill, the topography, and the nature of the soil and groundwater system.

If the volume of spilled oil is known or can be estimated, the depth to which the oil will penetrate 

before reaching immobile saturation can be calculated. The calculation will be reasonably 

accurate only where soils are more or less homogeneous. Still, if the depth to the water table is 

known, it is easy to estimate whether the oil is likely to initially migrate into groundwater. If the 

risk exists and if time permits, excavation of the contaminated soil should be considered. 

Excavated soil can then be cleansed or removed to a disposal site. If excavation is impractical or 

impossible, plans should be made to recover the oil while it is still localized in the subsurface, 

using the best available methods.
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Seepage often has been discovered during construction projects when oil or oil-contaminated 

water has flowed into an excavation. This illustrates two key principles: a seepage problem is not 

necessarily preceded by a surface spill, and oil will migrate under gravitational forces and with 

moving groundwater. The second point is the basis of the most widely used methods of removing 

oil from the soil or from an aquifer. These methods embrace three distinct procedures: removal 

of oil while it is still moving through the soil, but before it has reached the water table; removal 

of oil floating like a “pancake” on the groundwater; and removal of water contaminated with 

soluble fractions of the oil.

Effective cleanup of a significant spill on land requires equipment and machinery designed for 

moving earth, drilling, and pumping. Makeshift devices and methods should, as a rule, only be 

used temporarily and as a last resort. Speed is vital and every effort should be made to mobilize 

suitable equipment as soon as possible.

Rarely do conditions favor the recovery of moving oil after it has penetrated the surface, and 

before it has reached the water table. If the oil has penetrated only a few feet, and if highcapacity earthmovers are available, it may be possible to remove the contaminated soil.

Migrating oil will spread laterally over a layer of clay or other impermeable material. If such a 

layer lies near the surface, the oil might be recovered in ditches, using techniques similar to those 

for recovery from the water table (see Chapter 9, Oil Removal on Water, for details). Since such 

an impermeable layer will protect underlying groundwater, the consequences of forgoing a 

recovery attempt and allowing the oil to spread to immobile saturation should be considered.

10.6 GROUNDWATER REMOVAL

The primary method of recovering oil from the water table is by creating local depressions and 

withdrawal points in the water table. Regional water flow is interrupted by these depressions and 

all movement of oil and water within the depression cone is toward the withdrawal points 

(Figure 10-6 and 10-7). Oil floating on the water table within the depression is prevented from 

migrating further by removing it from the surface of the groundwater. The depression is 

commonly created by sinking wells and pumping water from them. The same result can be 

achieved with ditches, provided they can be dug to a depth below the groundwater table.
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Figure 10-6: Fluid Oil Floating on Water Table and Showing Elongation of 

“Pancake” in Direction of Water Movement

Figure 10-7: Oil on Water Table is Trapped in Cone of Depression 

Created by Drawdown of Pumping Well

This second method involves constructing a ditch across the entire front of the migrating body of 

oil and below the top of the water table. As the oil floats across the ditch, it is skimmed off the 

surface of the water (Figure 10-8). While this method is much less efficient than lowering the 

water table, it also produces much less fluid to be handled at the surface and is less costly. Under 

certain conditions, usually with a small spill, the method might be preferable. Its effectiveness 

depends on proper location of the ditch across the downstream end of the spill.
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Figure 10-8: Oil Moving with Shallow Groundwater Intercepted by Ditch Constructed 

Across Migration Path

Because of the need for rapid action, the steps taken immediately after an oil spill on land 

generally precede any real assessment of the extent of the contamination. If groundwater seems 

likely to be affected, however, such data will be required. Thorough investigation increases the 

effectiveness of subsequent cleanup operations. The main purpose of the investigation is to 

determine the number, type, and optimum locations of recovery points.
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The investigation normally is made by means of inspection holes and ditches, as described 

below. Inspection holes must extend several feet below the water table and should be designed to 

permit easy sampling and measuring of water levels. Grease, oil, or gasoline from machinery

must be kept out of the holes to avoid erroneous data.

The best locations for inspection holes most often will be just beyond the surface limit of the 

spill. If a hole is found to be contaminated, another must be drilled farther out. Contaminated 

inspection wells, however, can double as recovery points. Once a series of inspection wells has 

isolated the contaminated area, the wells must be monitored periodically for later spread of the 

contaminant. The holes also may be useful in evaluating the development of the depression 

created in the water table by the recovery wells.

Ditches are an efficient method of removing oil if the water table is sufficiently shallow. Ditches 

more than 6 to 8 feet deep are usually impractical, but the limitation is imposed by the ditching 

equipment that is available and the extent to which the soil will support the walls of the ditch 

without caving. Ditches in unconsolidated soils must have gently sloping sides, and a large 

amount of soil must be removed relative to the depth of the ditch.

If the ditch is to be used as a withdrawal point to lower the water table, it should be at least 3 or 4 

feet below the water table, and pumping capacity should be great enough to keep the water 

drawdown to the bottom of the ditch. Width is important only in that the ditch must be wide 

enough to accommodate the necessary pumps or other removal devices.

If the ditch is to be a collection point for skimming, its downstream wall should be lined with an 

impermeable material such as polyethylene film (Figure 10-9), which will block floating oil but 

permit water to pass below. Skimming must be continuous or collected oil will tend to move to 

the ends of the ditch and pass around the barrier.

Figure 10-9: System for Skimming Water Surface in Ditches or Wells
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Ditches need not be left open. One approach is to lay a string of perforated culvert pipe in the 

bottom and backfill the ditch with very porous material such as broken rock or gravel. Fluid 

enters the pipe through the perforations and can be removed through an opening left in the 

backfill for the purpose. Sometimes an intercepting ditch can be filled with straw to sorb the oil. 

The straw can be replaced periodically as it becomes saturated.

Fluid should be recovered from wells by the use of pumps. In the initial emergency, any kind of 

pump may be used, such as a boat-bailing pump or a hand-operated water well pump. As soon as 

possible, however, a standard well pump normally should be installed. Discharge capacities 

range from a few to about 100 gallons per minute, depending on pump size, casing diameter, and 

depth. Most such pumps require 5- or 6-inch casing. Submersible pumps, though highly efficient, 

should be used with caution since some types burn out quickly if operated dry. For depths to 

about 25 feet, gasoline-powered suction pumps are suitable for extended use and are widely 

available.

High-speed, rotary pumps should be avoided when pumping combinations of oil and water. They 

tend to encourage formation of oil-water emulsions that complicate separation at the surface.

The effects of well pumping from different depths are shown in Figures 10-10 and 10-11. The 

contaminated soil is relatively permeable, and the oil has migrated to the water table and spread 

there as a pancake. In Figure 10-10, Well ‘A’ does not extend into the pancake and pumping will 

recover a small and insignificant amount of the oil that is migrating to the water table. Well ‘B’ 

extends into the pancake and will produce oil from it initially, but the flow will fall quickly to a 

very low rate. The pancake is too thin to permit effective direct recovery. Well ‘C’ extends into 

the water table. It will produce water at first, but soon will begin to recover the floating oil as the 

fluid at the top of the water table is drawn down to the pump (Figure 10-11).

Figure 10-10: Typical Conditions During Latter Stage of Migration of Oil to Water Table
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Figure 10-11: Effect on Water Table of Pumping from Well C

The water table is lowered at the withdrawal point of Well ‘C’ because water is removed faster 

than the soil’s permeability allows it to be replenished. Both water and oil from the pancake are 

then drawn toward Well ‘C’ by the pressure differential. Water must be pumped from Well ‘C’ 

fast enough to create a depression cone that extends beyond the oil pancake and is deep enough 

to reverse the natural gradient of the water table. The oil will be prevented from flowing with 

groundwater away from the withdrawal point. With large spills, several wells may be required to 

depress the water table adequately over the necessary area.

Since permeability varies infinitely, no quantitative standards exist that apply to the depressionforming process in all areas. Figure 10-12 shows the development of an actual depression cone in 

an aquifer test near Saratoga Springs, N.Y. Precise selected data from the test are shown in 

Figure 10-13. The aquifer was 75 feet thick and consisted of fine to coarse, silty sand of 

moderately high permeability. It can be seen that the cone develops rapidly at first, and then 

spreads with decreasing speed.
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Figure 10-12: Diagrammatic Illustration of Development of a Cone of Depression Based on 

an Actual Aquifer Test

Scale Is Approximate. For Precise Data Plot, See Figure 10-13.

Figure 10-13: Selected Drawdown Data for an Aquifer Test

When enough data are available on an aquifer, the behavior of the depression cone some distance 

from the producing well can be calculated quite accurately. Within 100 to 200 feet of the well,
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however, local heterogeneities in the aquifer make such calculations unreliable. A standard 

procedure is to sink two or three monitor wells in one or more straight lines away from the 

production well. By observing fluid levels in these wells, the exact time and amount of 

drawdown can be determined. From these data, further expansion of the depression cone can be 

predicted. Withdrawal rates should be adjusted, ideally, to maintain a cone large enough only to 

contain the oil. Creation of an unnecessarily large cone results in production of a large volume of 

uncontaminated water from beyond the area of the spill.

The average depression cone actually is much shallower than is suggested by Figure 10-14, in 

which horizontal distances are in feet and vertical distances in inches. If the water table is 

horizontal, a shallow depression normally will suffice to confine the floating oil. If the water 

table is inclined, which it usually is, the cone must be deep enough to reverse the resulting 

gradient. The point at which the reveal occurs is the water table “divide.” If the oil is to be 

contained effectively, the divide must lie beyond the contaminated area.

Figure 10-14: Drawdown Configuration of Well Pumping From Inclined Water 

Fluid at the surface of the water table between the divide and outer limit of cone will not be

trapped, but will move down gradient with the water.

The data of Figure 10-13 may not be precisely applicable to any other area. However, the data 

demonstrate that in a good aquifer a depression cone of considerable extent can probably be 

created in a matter of minutes or hours. This is enough time in most cases to install a recovery 

system before the oil can be carried out of reach by moving groundwater. The importance of the 

drawdown in relation to the gradient also must be kept in mind. The complexities described here 

and others not covered indicate the advisability of securing professional counsel.

Although a depression cone can be maintained by pumping from far below the surface of the 

water table, floating oil will not be recovered unless the surface is drawn down to the withdrawal 

point. It is, therefore, more effective to use two pumps instead of one. The larger pump is used to 

maintain the depression, while the smaller is arranged to pump the oil from the surface of the 

water (Figure 10-15). This method also tends to minimize the volume of fluid that must be 

separated at the surface.
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Depending on the seriousness of the spill, pumping may be required for weeks or months. 

Ideally, pumping should be continued through several fluctuations of the water table and 

abandoned only after the contamination has been reduced to an acceptable level.

Figure 10-15: Well Pumping Using Two Pumps

Well A is maintaining depression and recovering oil in a single operation by drawing the 

fluid surface down to the pump level. Well B is maintaining depression by pumping clean 

water from below the water table. Floating oil is recovered by a suction pump at the fluid 

surface.

Recovery wells must be operated until the aquifer is no longer threatened by oil leached from the 

soil by percolating surface water. It may be possible to speed the leaching process by irrigating 

or flooding the soil above the contaminated zone, vastly increasing the volume of percolating 

water. Another approach that has been suggested is “miscible drive” by a harmless, waterinsoluble oil, such as a purely paraffinic hydrocarbon.

This material, being miscible with the contaminant, would dissolve and extract it more quickly 

and completely than water. Left behind in the soil would be a harmless residue of the extracting 

oil to be consumed by natural processes. If such exotic processes are indicated, they should be 

planned carefully by qualified people and be acceptable to EPA and local pollution control 

authorities.

Water produced from an oil-contaminated reservoir may contain both fluid and dissolved 

petroleum products, which must be removed before the water is allowed to return to the 

groundwater. Oily fluids can be removed from the water by a gravity separator as discussed in 

Chapter 6 or by filtering.
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10.7 GROUNDWATER ABSORPTION

In certain cases, it may be possible to absorb oil from groundwater using a recently developed 

method. This method uses oil absorbent polymers contained in “extraction socks” for retrieving 

oil from contaminated groundwater. The polymers must be of the true absorbent types that will 

not allow the absorbed oil to be released again once absorbed.

The socks are allowed to soak in the extraction well for a period of time (usually up to a week). 

When the socks are pulled out of the wells, only the water runs out, not the oil. This method 

could not be considered where groundwater is moving at an appreciable rate or for larger oil 

spills. Applicability might best be determined by the appropriate state authority.

10.8 SOIL WASHING

In suitable conditions, much oil can be recovered from loose, excavated soil by water washing 

with a high-pressure hose. The soil can be placed on the edge of a pit and washed into the pit 

with a fire hose. The oil floats to the surface of the resulting pond and can be skimmed off.

This procedure might also be used on-site. The contaminated soil would be excavated to form a 

pit, which then would be lined with an impermeable material such as plastic sheeting or clay. 

The soil could be washed back into the pit and the oil skimmed off. This approach would reduce 

trucking costs greatly.
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CHAPTER 11 

OIL DISPOSAL

11.1 RECLAMATION

Once an oil spill has been contained and harvested, the next step in completing the job is the 

disposal of the harvested material in a satisfactory and approved manner. This can be 

accomplished by using one or a combination of four basic disposal methods:

• Transport to oil reclamation centers

• Burning on site or at preselected burning pits, incinerators, or generating stations

• Burial on site or at approved distant sites

• Land spreading (land farming) at approved sites

Before determining which method of waste disposal should be used, local and state authorities 

should be consulted as to possible restrictions and special sites that may be available. In addition, 

any insulating oil that is to be disposed of should be tested for PCB concentration levels and 

should be disposed of accordingly. See EPA regulations 40 CFR 761 for further details of PCB 

disposal.

11.2 BURNING

In addition to state regulations, local governments have adopted regulations concerning open pit 

burning and incineration. Therefore, thorough knowledge of the local and state laws is a 

prerequisite to consideration of burning a recovered oil spill, whether debris-laden or not. In any 

event, permits must be obtained where required.

When possible, burning a recovered oil spill with accompanying debris near the site of cleanup is 

preferable to using distant sites because the recovered oil may be more volatile during the early 

stages and will burn more efficiently, with less ash or residue. Transportation costs and the risk 

of further damage to the environment also will be reduced from possible spillage along the route. 

Such on-site burning should be done sufficiently distant from any area that may be used for 

human, animal, or feed occupancy. Burning should be done only when and where prevailing 

winds will carry the smoke over the least inhabited area.

Burning any accumulation of oil or oily debris should be monitored at all times by personnel 

experienced in the behavior of open fires. Proper equipment should be at the burn sites to control 

the burn and to extinguish it if necessary. Local municipal or volunteer fire departments can 

provide the experienced personnel and equipment.

Open pit burning of free and relatively clean oil will normally leave very little residue; however, 

a debris-laden oil will not burn with such efficiency, leaving a significant amount of unburned 

trash along with some ash. This can be buried readily if a pit has been provided. Therefore, when 

oily debris is to be burned, a pit deep enough to hold the residue should be dug at a suitable 

location where burial can be accomplished by simply backfilling the hole.
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11.3 INCINERATION

Incineration is the least polluting method of burning. It is, however, the most costly, not readily 

available, and requires preparation of the material into a form that can be fed into the incinerator. 

The cost of incineration, including transport to the incinerator, can be equal to or greater than all 

other costs of a cleanup operation. Therefore, before employing this system of disposal, carefully

consider the alternatives. However, existing regulations may leave no other alternative. Some 

type of acceptable incineration is available in major metropolitan areas, but not usually in the rest 

of the nation. For remote areas, incineration would require long transport of the waste to such a 

site.

Incinerators vary in size and shape and will only receive material in a certain form. Therefore, if 

incineration is to be used, the material will have to be prepared in the proper form. Trash 

grinding machines that may be necessary may not be available.

11.4 GENERATING STATION DISPOSAL

An alternative to formal incineration, which is far less costly, is the burning of this oil-laden soil, 

debris, and sorbent material in coal generating station boilers. This material should be spread 

over the coal pile in thin layers to insure complete combustion. Care should be exercised, as 

discussed previously, to ensure that the size and shape of the materials being disposed of will not 

interfere with the operation of the conveyor system and pulverizers. This system of disposal 

should work particularly well in areas where lignite coal is the primary energy source.

11.5 BURIAL

Burial of recovered oil, debris laden or not, should not be done indiscriminately. In most states, 

burial must be at an approved site. Sanitary landfills, industrial disposal sites, and/or fly ash 

disposal sites will usually be able to handle small amounts of oil wastes. For burying large 

volumes of oil material, a special site may have to be selected, approved, and constructed—and 

that usually means great expense. In obtaining the use of specified burial sites, several factors 

must be considered.

For any burial site considered, oily waste disposal must be compatible with surrounding land 

uses. Residential, recreational, or industrial sites nearby may preclude the use of an otherwise 

ideal site. On the other hand, it might be less difficult to find an approved site near such areas. 

The use of prime agricultural or potential residential land cannot be automatically discounted, 

since it may be the only site that is finally approved.

An important factor in narrowing site choices is the suitability of the land for oily waste burial. 

The site’s characteristics must not allow the buried oil to become a source of groundwater or 

surface water pollution (see Chapter 10). Soil conditions, subsurface hydrology, geologic 

structure, and surface topography all must be considered in deciding on the suitability of a site.

Soil conditions will determine the potential migration—upward, downward, or laterally—of the 

buried oil. A loose, unconsolidated sand or gravel bed in a potential site area would not be
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suitable, especially in high rainfall areas. Oil can migrate in any direction in this type of soil. A 

loosely packed backfill can permit upward percolation and surface exposure. Heavy rainfall 

would accentuate the rise to the surface. Oil in earthen pits has been known to migrate upward by 

either capillary action or by a rise in water level. This oil can contaminate the surface area of the 

pit, and, to a lesser degree, the soil a good distance from the pit. This could condemn the use of 

that portion of land for many years to come.

Obviously, selection of a suitable site for burial of oily wastes requires specialized knowledge, 

which is best obtained from engineers and scientists familiar with a particular area.

Once the suitability of potential sites has been determined, landowner, public, and/or 

governmental agency opposition to the use of the site for oily waste burial will affect whether the 

site selected is in a rural, agricultural, or a higher density area. Selection and approval of a burial 

site ultimately may be made after a series of compromises among the various opposing interests.

11.6 LAND SPREADING (LAND FARMING)

This is the term given to disposal of oil or oily debris by mixing it with soil to promote aerobic 

degradation. Land farming is the most sophisticated method of disposing of oily waste or debris. 

Also, it is probably the best from an overall environmental aspect. The microbes “eat” the oil and 

use it for their energy, with CO2 as their waste product. When the oil is depleted, the microbes 

die out and all that is left is clean soil. Many variables must be carefully reviewed before 

undertaking a land farm operation.

Site selection is the first prerequisite. The larger the volume of oil for disposal or the greater the 

oil concentration, the more land area that will be needed. Depth of suitable soil plays a role. The 

deeper the farming, the less surface area is required.

The type of oily waste or oily debris, along with the physical and chemical properties of the oil, 

must be known to determine the soil’s suitability and compatibility with the oil. Major errors or 

oversights here could result in causing damage instead of alleviating a problem.

Once compatibility of the oily debris and soil has been established by local experts, preparing the 

soil and stockpiling the waste for burial can proceed. This requires proper and adequate 

equipment as well as experienced operators.

Preparing the soil is not an easy task. It is recommended that brush and rocks 6 inches or more in 

diameter be removed, as they inhibit proper soil/oil mixing. The site should be leveled to a 1 

percent or 2 percent grade. The soil should be scarified 1 to 2 inches in a cold climate, or 3 to 4 

inches in warmer climates. It may be necessary to add soil nutrients to support the growth of 

hydrocarbon-consuming microbes.

The oily waste of debris must be prepared and stockpiled near the land farm site. It is 

recommended that it be spread over the scarified soil to a thickness of no more than 5 inches. 

Rototillers, harrows, or discs can be used to mix the oily debris and soil to depths of 4 to 5 

inches. Tilling the mixed elements then can follow, using normal agricultural procedures. It may
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be necessary to periodically remix the soil and debris to aerate the material and induce 

biodegradation. Some sites have been known to require plowing every 2 to 4 months. Once no 

oil is visible after remixing, the process can be considered complete and successful. Revegetation 

can follow.

Land farming may, indeed, be the answer for disposal of certain oily wastes and debris. It should 

not be undertaken without guidance from those experienced in the process, approval from 

regulatory agencies (State or Federal) and, finally, with the aid of a specialist knowledgeable 

about local soils and conditions.
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Appendix A

EPA REGIONAL OFFICES

Environmental Protection Agency (EPA) (Website www.epa.gov)

Region 1

Environmental Protection Agency 

1 Congress Street, Suite 1100

Boston, MA 02114-2023

Phone: 888-372-7341

Region 2

Environmental Protection Agency 

290 Broadway

New York, NY 10007-1866 

Phone: 212-637-3660

Region 3

Environmental Protection Agency 

1650 Arch Street (3PM52) 

Philadelphia, PA 19103-2029

Phone: 215-814-5000

Region 4

Environmental Protection Agency 

Sam Nunn Atlanta Federal Center 

61 Forsyth Street, SW

Atlanta, GA 30303-3104

Phone: 404-562-9900

Region 5

Environmental Protection Agency 

77 W Jackson Blvd

Chicago, IL 60604

Phone: 312-353-2000

Region 6

Environmental Protection Agency 

1445 Ross Avenue

Suite 1200

Dallas, TX 75202

Phone: 214-665-6444

Region 7

Environmental Protection Agency 

Office of External Program

901 N 5th Street

Kansas City, KS 66101 

Phone: 913-551-7003

Region 8

US EPA Region 8 

80C-EISC

1595 Wynkoop St.

Denver, CO 80202-1129

Phone: 303-312-6312

Region 9

Environmental Protection Agency 

75 Hawthorne Street

San Francisco, CA 94105 

Phone: 415-947-8000

Region 10

US EPA Region 10

1200 Sixth Avenue Suite 900

Seattle, WA 98101

Phone: 206-553-1200
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REGIONS

4 – Alabama

10 – Alaska

9 – Arizona

6 – Arkansas

9 – California

8 – Colorado

1 – Connecticut

3– Delaware 

3 – D. C.

4– Florida

4 – Georgia

9– Hawaii

10– Idaho

5 – Illinois

5 – Indiana

7 – Iowa

7 – Kansas

4 – Kentucky

6 – Louisiana

REGIONS

1 – Maine

3 – Maryland

1 – Massachusetts

5 – Michigan

5 – Minnesota

4 - Mississippi

7– Missouri

8– Montana

7 – Nebraska

9 – Nevada

1 – New Hampshire 

2 – New Jersey

6 – New Mexico 

2 – New York

4 – North Carolina 

8 – North Dakota 

5 – Ohio

6 – Oklahoma

10 – Oregon

REGIONS

3 – Pennsylvania 

1 – Rhode Island 

4 – South Carolina 

8 – South Dakota 

4 – Tennessee

6 – Texas

8 – Utah

1 – Vermont

3 – Virginia

10 – Washington 

3 – West Virginia 

5 – Wisconsin

8– Wyoming

9– American Samoa 

9 – Guam

2 – Puerto Rico

2 – Virgin Islands
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APPENDIX B

Normal Precipitation Tables

From “Comparative Climatic Data for United States Through 2000” 

National Oceanic and Atmospheric Administration

National Climatic Data Center 

Asheville, North Carolina
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Page B-2

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Birmingham Airport, Ala. 30 5.45 4.21 6.10 4.67 4.83 3.78 5.09 3.48 4.05 3.23 4.63 4.47 53.99

Huntsville, Ala. 30 5.52 4.95 6.68 4.54 5.24 4.22 4.40 3.32 4.29 3.54 5.22 5.59 57.51

Mobile, Ala. 30 5.75 5.10 7.20 5.06 6.10 5.01 6.54 6.20 6.01 3.25 5.41 4.66 66.29

Montgomery, Ala. 30 5.04 5.45 6.39 4.38 4.14 4.13 5.31 3.63 4.22 2.58 4.53 4.97 54.77

Anchorage, Alaska 30 0.68 0.74 0.65 0.52 0.69 1.06 1.70 2.93 2.87 2.08 1.09 1.05 16.08

Annette, Alaska 30 9.67 8.05 7.96 7.37 5.73 4.72 4.26 6.12 9.49 13.86 12.21 11.39 100.83

Barrow, Alaska 30 0.12 0.12 0.09 0.12 0.12 0.32 0.87 1.04 0.69 0.39 0.16 0.12 4.16

Bethel, Alaska 30 0.62 0.51 0.67 0.65 0.85 1.60 2.03 3.02 2.31 1.43 1.37 1.12 16.18

Bettles, Alaska 30 0.84 0.61 0.55 0.38 0.85 1.43 2.10 2.54 1.82 1.08 0.90 0.87 13.97

Big Delta, Alaska 30 0.34 0.41 0.22 0.20 0.77 2.38 2.77 2.11 1.03 0.73 0.59 0.39 11.94

Cold Bay, Alaska 30 3.08 2.59 2.48 2.30 2.65 2.89 2.53 3.59 4.51 4.54 4.79 4.33 40.28

Fairbanks, Alaska 30 0.56 0.36 0.28 0.21 0.60 1.40 1.73 1.74 1.12 0.92 0.68 0.74 10.34

Gulkana, Alaska 30 0.45 0.52 0.36 0.22 0.59 1.54 1.82 1.80 1.44 1.02 0.67 0.97 11.40

Homer, Alaska 30 2.61 2.04 1.82 1.21 1.07 0.96 1.45 2.28 3.37 2.77 2.87 3.00 25.45

Juneau, Alaska 30 4.81 4.02 3.51 2.96 3.48 3.36 4.14 5.37 7.54 8.30 5.43 5.41 58.33

King Salmon, Alaska 30 1.03 0.72 0.79 0.94 1.35 1.70 2.15 2.89 2.81 2.09 1.54 1.39 19.41

Kodiak, Alaska 30 8.17 5.72 5.22 5.48 6.31 5.38 4.12 4.48 7.84 8.36 6.63 7.64 75.35

Kotzebue, Alaska 30 0.55 0.42 0.38 0.41 0.33 0.57 1.43 2.00 1.70 0.95 0.71 0.60 10.05

McGrath, Alaska 30 1.04 0.74 0.81 0.66 1.02 1.45 2.32 2.75 2.36 1.46 1.46 1.44 17.51

Nome, Alaska 30 0.92 0.75 0.60 0.65 0.74 1.14 2.15 3.23 2.51 1.58 1.28 1.01 16.56

St. Paul Island, Alaska 30 1.74 1.25 1.12 1.12 1.21 1.41 1.91 2.96 2.79 2.70 2.87 2.13 23.21

Talkeetna, Alaska 30 1.45 1.28 1.26 1.22 1.64 2.41 3.24 4.53 4.35 3.06 1.78 1.96 28.18

Unalakleet, Alaska 30 0.40 0.31 0.39 0.35 0.55 1.25 2.15 2.92 2.10 0.89 0.66 0.47 12.44

Valdez, Alaska 30 6.02 5.53 4.49 3.55 3.08 3.01 3.84 6.62 9.59 8.58 5.51 7.59 67.41

Yakutat, Alaska 30 13.18 10.99 11.41 10.80 9.78 7.17 7.88 13.27 20.88 24.00 15.17 15.85 160.38

Flagstaff, Ariz. 30 2.18 2.56 2.62 1.29 0.80 0.43 2.40 2.89 2.12 1.93 1.86 1.83 22.91

Phoenix, Ariz. 30 0.83 0.77 1.07 0.25 0.16 0.09 0.99 0.94 0.75 0.79 0.73 0.92 8.29

Tucson, Ariz. 30 0.99 0.88 0.81 0.28 0.24 0.24 2.07 2.30 1.45 1.21 0.67 1.03 12.17

Winslow, Ariz. 30 0.46 0.53 0.61 0.27 0.36 0.30 1.18 1.31 1.02 0.90 0.55 0.54 8.03

Yuma, Ariz. 30 0.38 0.28 0.27 0.09 0.05 0.02 0.23 0.61 0.26 0.26 0.14 0.42 3.01
Bulletin 1724E-302

Page B-3

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Ann.

Fort Smith, Ark. 30 2.37 2.59 3.94 3.91 5.29 4.28 3.19 2.56 3.61 3.94 4.80 3.39 43.87

Little Rock, Ark. 30 3.61 3.33 4.88 5.47 5.05 3.95 3.31 2.93 3.71 4.25 5.73 4.71 50.93

North Little Rock, Ark. 30 3.37 3.27 4.88 5.03 5.40 3.51 3.15 2.97 3.53 3.81 5.74 4.53 49.19

Bakersfield, Calif. 30 1.18 1.21 1.41 0.45 0.24 0.12 0.00 0.08 0.15 0.30 0.59 0.76 6.49

Bishop, Calif. 30 0.88 0.97 0.62 0.24 0.26 0.21 0.17 0.13 0.28 0.20 0.44 0.62 5.02

Eureka, Calif.. 30 5.97 5.51 5.55 2.91 1.62 0.65 0.16 0.38 0.86 2.36 5.78 6.35 38.10

Fresno, Calif. 30 2.16 2.12 2.20 0.76 0.39 0.23 0.01 0.01 0.26 0.65 1.10 1.34 11.23

Long Beach, Calif. 30 2.95 3.01 2.43 0.60 0.23 0.08 0.02 0.10 0.24 0.40 1.12 1.76 12.94

Los Angeles Airport, Calif. 30 2.98 3.11 2.40 0.63 0.24 0.08 0.03 0.14 0.26 0.36 1.13 1.79 13.15

Los Angeles C.O., Calif. 30 3.33 3.68 3.14 0.83 0.31 0.06 0.01 0.13 0.32 0.37 1.05 1.91 15.14

Mount Shasta, Calif. 30 7.06 6.45 5.81 2.65 1.87 0.99 0.39 0.43 0.87 2.21 5.08 5.35 39.16

Redding, Calif. 30 6.50 5.49 5.15 2.40 1.66 0.69 0.05 0.22 0.48 2.18 4.03 4.67 33.52

Sacramento, Calif. 30 3.84 3.54 2.80 1.02 0.53 0.20 0.05 0.06 0.36 0.89 2.19 2.45 17.93

San Diego, Calif. 30 2.28 2.04 2.26 0.75 0.20 0.09 0.03 0.09 0.21 0.44 1.07 1.31 10.77

San Francisco Airport, Calif. 30 4.45 4.01 3.26 1.17 0.38 0.11 0.03 0.07 0.20 1.04 2.49 2.89 20.11

San Francisco C.O., Calif. 30 4.72 4.15 3.40 1.25 0.54 0.13 0.04 0.09 0.28 1.19 3.31 3.18 22.28

Santa Barbara, Calif. 30 3.57 4.28 3.51 0.63 0.23 0.05 0.03 0.11 0.42 0.52 1.32 2.26 16.93

Santa Maria, Calif. 30 2.64 3.23 2.94 0.91 0.32 0.05 0.03 0.05 0.31 0.45 1.24 1.84 14.01

Stockton, Calif. 30 2.71 2.46 2.28 0.96 0.50 0.09 0.05 0.05 0.33 0.82 1.77 1.82 13.84

Alamosa, Colo. 30 0.25 0.21 0.46 0.54 0.70 0.59 0.94 1.19 0.89 0.67 0.48 0.33 7.25

Colorado Springs, Colo. 30 0.28 0.35 1.06 1.62 2.39 2.34 2.85 3.48 1.23 0.86 0.52 0.42 17.40

Denver, Colo. 30 0.51 0.49 1.28 1.93 2.32 1.56 2.16 1.82 1.14 0.99 0.98 0.63 15.81

Grand Junction, Colo. 30 0.60 0.50 1.00 0.86 0.98 0.41 0.66 0.84 0.91 1.00 0.71 0.52 8.99

Pueblo, Colo. 30 0.33 0.26 0.97 1.25 1.49 1.33 2.04 2.27 0.84 0.64 0.58 0.39 12.39

Bridgeport, Conn. 30 3.73 2.92 4.15 3.99 4.03 3.57 3.77 3.75 3.58 3.54 3.65 3.47 44.15

Hartford, Conn. 30 3.84 2.96 3.88 3.86 4.39 3.85 3.67 3.98 4.13 3.94 4.06 3.60 46.16

Wilmington, Del. 30 3.43 2.81 3.97 3.39 4.15 3.59 4.28 3.51 4.01 3.08 3.19 3.40 42.81

Washington Dulles Ap, D.C. 30 3.05 2.77 3.55 3.22 4.22 4.07 3.57 3.78 3.82 3.37 3.31 3.07 41.80

Washington Nat’l Ap, D.C. 30 3.21 2.63 3.60 2.77 3.82 3.13 3.66 3.44 3.79 3.22 3.03 3.05 39.35

Apalachicola, Fla. 30 4.87 3.76 4.95 3.00 2.62 4.30 7.31 7.29 7.10 4.18 3.62 3.51 56.51
Bulletin 1724E-302 

Page B-4

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Daytona Beach, Fla. 30 3.13 2.74 3.84 2.54 3.26 5.69 5.17 6.09 6.61 4.48 3.03 2.71 49.29

Fort Myers, Fla. 30 2.23 2.10 2.74 1.67 3.42 9.77 8.98 9.54 7.86 2.59 1.71 1.58 54.19

Gainesville, Fla. 30 3.51 3.39 4.26 2.86 3.23 6.78 6.10 6.63 4.37 2.50 2.17 2.56 48.36

Jacksonville, Fla. 30 3.69 3.15 3.93 3.14 3.48 5.37 5.97 6.87 7.90 3.86 2.34 2.64 52.34

Key West, Fla. 30 2.22 1.51 1.86 2.06 3.48 4.57 3.27 5.40 5.45 4.34 2.64 2.14 38.94

Miami, Fla. 30 1.88 2.07 2.56 3.36 5.52 8.54 5.79 8.63 8.38 6.19 3.43 2.18 58.53

Orlando, Fla. 30 2.43 2.35 3.54 2.42 3.74 7.35 7.15 6.25 5.76 2.73 2.32 2.31 48.35

Pensacola, Fla. 30 5.34 4.68 6.40 3.89 4.40 6.39 8.02 6.85 5.75 4.13 4.46 3.97 64.28

Tallahassee, Fla. 30 5.36 4.63 6.47 3.59 4.95 6.92 8.04 7.03 5.01 3.25 3.86 4.10 63.21

Tampa, Fla. 30 2.27 2.67 2.84 1.80 2.85 5.50 6.49 7.60 6.54 2.29 1.62 2.30 44.77

Vero Beach, Fla. 30 2.89 2.45 4.20 2.88 3.80 6.03 6.53 6.04 6.84 5.04 3.04 2.19 51.93

West Palm Beach, Fla. 30 3.75 2.55 3.68 3.57 5.39 7.58 5.97 6.65 8.10 5.46 5.55 3.14 61.39

Athens, Ga. 30 4.69 4.39 4.99 3.35 3.86 3.94 4.41 3.78 3.53 3.47 3.71 3.71 47.83

Atlanta, Ga. 30 5.02 4.68 5.38 3.62 3.95 3.63 5.12 3.67 4.09 3.11 4.10 3.82 50.20

Augusta, Ga. 30 4.50 4.11 4.61 2.94 3.07 4.19 4.07 4.48 3.59 3.20 2.68 3.14 44.58

Columbus, Ga. 30 4.78 4.48 5.75 3.84 3.62 3.51 5.04 3.78 3.07 2.33 3.97 4.40 48.57

Macon, Ga. 30 5.00 4.55 4.89 3.14 2.98 3.54 4.32 3.79 3.26 2.37 3.22 3.93 45.00

Savannah, Ga. 30 3.95 2.92 3.64 3.32 3.61 5.49 6.04 7.20 5.08 3.12 2.40 2.81 49.58

Hilo, Hawaii 30 9.74 8.86 14.35 12.54 8.07 7.36 10.71 9.78 9.14 9.64 15.58 10.50 126.27

Honolulu, Hawaii 30 2.73 2.35 1.89 1.11 0.78 0.43 0.50 0.46 0.74 2.18 2.26 2.85 18.29

Kahului, Hawaii 30 3.74 2.36 2.35 1.75 0.66 0.23 0.49 0.53 0.39 1.05 2.17 3.08 18.80

Lihue, Hawaii 30 4.59 3.26 3.58 3.00 2.87 1.82 2.12 1.91 2.69 4.25 4.70 4.78 39.57

Boise, Idaho 30 1.39 1.14 1.41 1.27 1.27 0.74 0.39 0.30 0.76 0.76 1.38 1.38 12.19

Lewiston, Idaho 30 1.14 0.95 1.12 1.30 1.56 1.16 0.72 0.75 0.80 0.96 1.21 1.05 12.74

Pocatello, Idaho 30 1.14 1.01 1.38 1.18 1.51 0.91 0.70 0.66 0.89 0.97 1.13 1.10 12.58

Chicago, Ill. 30 1.75 1.63 2.65 3.68 3.38 3.63 3.51 4.62 3.27 2.71 3.01 2.43 36.27

Moline, Ill. 30 1.58 1.51 2.92 3.82 4.25 4.63 4.03 4.41 3.16 2.80 2.73 2.20 38.04

Peoria, Ill. 30 1.50 1.67 2.83 3.56 4.17 3.84 4.02 3.16 3.12 2.76 2.99 2.40 36.03

Rockford, Ill. 30 1.41 1.34 2.39 3.62 4.02 4.80 4.10 4.21 3.47 2.57 2.63 2.06 36.63

Springfield, Ill. 30 1.62 1.80 3.15 3.36 4.06 3.77 3.53 3.41 2.83 2.62 2.87 2.54 35.56
Bulletin 1724E-302

Page B-5

Normal Monthly Precipitation (Inches)

Normals 1971-2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Evansville, Ind. 30 2.91 3.10 4.29 4.48 5.01 4.10 3.75 3.14 2.99 2.78 4.18 3.54 44.27

Fort Wayne, Ind. 30 2.05 1.94 2.86 3.54 3.75 4.04 3.58 3.60 2.81 2.63 2.98 2.77 36.55

Indianapolis, Ind. 30 2.48 2.41 3.44 3.61 4.35 4.13 4.42 3.82 2.88 2.76 3.61 3.03 40.95

South Bend, Ind. 30 2.27 1.98 2.89 3.62 3.50 4.19 3.73 3.98 3.79 3.27 3.39 3.09 39.70

Des Moines, Iowa 30 1.03 1.19 2.21 3.58 4.25 4.57 4.18 4.51 3.15 2.62 2.10 1.33 34.72

Dubuque, Iowa 30 1.28 1.42 2.57 3.49 4.12 4.08 3.73 4.59 3.56 2.50 2.49 1.69 35.52

Sioux City, Iowa 30 0.59 0.62 2.00 2.75 3.75 3.61 3.30 2.90 2.42 1.99 1.40 0.66 25.99

Waterloo, Iowa 30 0.84 1.05 2.13 3.23 4.15 4.82 4.20 4.08 2.95 2.49 2.10 1.11 33.15

Concordia, Kan. 30 0.66 0.73 2.35 2.45 4.20 3.95 4.20 3.24 2.50 1.84 1.45 0.86 28.43

Dodge City, Kan. 30 0.62 0.66 1.84 2.25 3.00 3.15 3.17 2.73 1.70 1.45 1.01 0.77 22.35

Goodland, Kan. 30 0.43 0.44 1.20 1.51 3.46 3.30 3.54 2.49 1.12 1.05 0.82 0.40 19.76

Topeka, Kan. 30 0.95 1.18 2.56 3.14 4.86 4.88 3.83 3.81 3.71 2.99 2.31 1.42 35.64

Wichita, Kan. 30 0.84 1.02 2.71 2.57 4.16 4.25 3.31 2.94 2.96 2.45 1.82 1.35 30.38

Greater Cincinnati Airport 30 2.92 2.75 3.90 3.96 4.59 4.42 3.75 3.79 2.82 2.96 3.46 3.28 42.60

Jackson, Ky. 30 3.56 3.68 4.38 3.79 5.16 4.67 4.59 4.13 3.77 3.18 4.20 4.27 49.38

Lexington, Ky. 30 3.34 3.27 4.41 3.67 4.78 4.58 4.80 3.77 3.11 2.70 3.44 4.03 45.91

Louisville, Ky. 30 3.28 3.25 4.41 3.91 4.88 3.76 4.30 3.41 3.05 2.79 3.80 3.69 44.54

Paducah, Ky. 30 3.47 3.93 4.27 4.95 4.75 4.51 4.45 2.99 3.56 3.45 4.53 4.38 49.24

Baton Rouge, La. 30 6.19 5.10 5.07 5.56 5.34 5.33 5.96 5.86 4.84 3.81 4.76 5.26 63.08

Lake Charles, La. 30 5.52 3.28 3.54 3.64 6.06 6.07 5.12 4.85 5.95 3.94 4.61 4.60 57.19

New Orleans, La. 30 5.87 5.47 5.24 5.02 4.62 6.83 6.20 6.15 5.55 3.05 5.09 5.07 64.16

Shreveport, La. 30 4.60 4.21 4.18 4.42 5.25 5.05 3.99 2.71 3.21 4.45 4.68 4.55 51.30

Caribou, Maine 30 2.97 2.06 2.57 2.64 3.27 3.31 3.89 4.15 3.27 2.99 3.12 3.19 37.44

Portland, Maine 30 4.09 3.14 4.14 4.26 3.82 3.28 3.32 3.05 3.37 4.40 4.72 4.24 45.83

Baltimore, Md. 30 3.47 3.02 3.93 3.00 3.89 3.43 3.85 3.74 3.98 3.16 3.12 3.35 41.94

Blue Hill, Mass. 30 4.78 4.06 4.79 4.32 3.79 3.93 3.74 4.06 4.13 4.42 4.64 4.56 51.22

Boston, Mass. 30 3.92 3.30 3.85 3.60 3.24 3.22 3.06 3.37 3.47 3.79 3.98 3.73 42.53

Worcester, Mass. 30 4.07 3.10 4.23 3.92 4.35 4.02 4.19 4.09 4.27 4.67 4.34 3.80 49.05

Alpena, Mich. 30 1.76 1.35 2.13 2.31 2.61 2.53 3.17 3.50 2.80 2.33 2.08 1.83 28.40

Detroit, Mich. 30 1.91 1.88 2.52 3.05 3.05 3.55 3.16 3.10 3.27 2.23 2.66 2.51 32.89
Bulletin 1724E-302 

Page B-6

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Flint, Mich. 30 1.57 1.35 2.22 3.13 2.74 3.07 3.17 3.43 3.76 2.34 2.65 2.18 31.61

Grand Rapids, Mich. 30 2.03 1.53 2.59 3.48 3.35 3.67 3.56 3.78 4.28 2.80 3.35 2.70 37.13

Houghton Lake, Mich. 30 1.61 1.25 2.05 2.29 2.57 2.93 2.75 3.72 3.11 2.26 2.14 1.75 28.43

Lansing, Mich. 30 1.61 1.45 2.33 3.09 2.71 3.60 2.68 3.46 3.48 2.29 2.66 2.17 31.53

Marquette, Mich. 30 2.60 1.85 3.13 2.79 3.07 3.21 3.01 3.55 3.74 3.66 3.27 2.43 36.31

Muskegon, Mich. 30 2.22 1.58 2.36 2.91 2.95 2.58 2.32 3.77 3.52 2.80 3.23 2.64 32.88

Sault Ste. Marie, Mich. 30 2.64 1.60 2.41 2.57 2.50 3.00 3.14 3.47 3.71 3.32 3.40 2.91 34.67

Duluth, Minn. 30 1.12 0.83 1.69 2.09 2.95 4.25 4.20 4.22 4.13 2.46 2.12 0.94 31.00

International Falls, Minn. 30 0.84 0.64 0.96 1.38 2.55 3.98 3.37 3.14 3.03 1.98 1.36 0.70 23.93

Minneapolis-St.Paul, Minn. 30 1.04 0.79 1.86 2.31 3.24 4.34 4.04 4.05 2.69 2.11 1.94 1.00 29.41

Rochester, Minn. 30 0.94 0.75 1.88 3.01 3.53 4.00 4.61 4.33 3.12 2.20 2.01 1.02 31.40

Saint Cloud, Minn. 30 0.76 0.59 1.50 2.13 2.97 4.51 3.34 3.93 2.93 2.24 1.54 0.69 27.13

Jackson, Miss. 30 5.67 4.50 5.74 5.98 4.86 3.82 4.69 3.66 3.23 3.42 5.04 5.34 55.95

Meridian, Miss. 30 5.92 5.35 6.93 5.62 4.87 3.99 5.45 3.34 3.64 3.28 4.95 5.31 58.65

Tupelo, Miss. 30 5.14 4.68 6.30 4.94 5.80 4.82 3.65 2.67 3.35 3.38 5.01 6.12 55.86

Columbia, Mo. 30 1.73 2.20 3.21 4.16 4.87 4.02 3.80 3.75 3.42 3.18 3.47 2.47 40.28

Kansas City, Mo. 30 1.15 1.31 2.44 3.38 5.39 4.44 4.42 3.54 4.64 3.33 2.30 1.64 37.98

St. Louis, Mo. 30 2.14 2.28 3.60 3.69 4.11 3.76 3.90 2.98 2.96 2.76 3.71 2.86 38.75

Springfield, Mo. 30 2.11 2.28 3.82 4.31 4.57 5.02 3.56 3.37 4.83 3.47 4.46 3.17 44.97

Billings, Mont. 30 0.81 0.57 1.12 1.74 2.48 1.89 1.28 0.85 1.34 1.26 0.75 0.67 14.77

Glasgow, Mont. 30 0.35 0.26 0.47 0.75 1.72 2.20 1.78 1.25 0.98 0.71 0.39 0.37 11.23

Great Falls, Mont. 30 0.68 0.51 1.01 1.40 2.53 2.24 1.45 1.65 1.23 0.93 0.59 0.67 14.89

Havre, Mont. 30 0.47 0.36 0.70 0.87 1.84 1.90 1.51 1.20 1.03 0.62 0.45 0.51 11.46

Helena, Mont. 30 0.52 0.38 0.63 0.91 1.78 1.82 1.34 1.29 1.05 0.66 0.48 0.46 11.32

Kalispell, Mont. 30 1.47 1.15 1.11 1.22 2.04 2.30 1.41 1.25 1.20 0.96 1.45 1.65 17.21

Missoula, Mont. 30 1.06 0.77 0.96 1.09 1.95 1.73 1.09 1.15 1.08 0.83 0.96 1.15 13.82

Grand Island, Neb. 30 0.54 0.68 2.04 2.61 4.07 3.72 3.14 3.08 2.43 1.51 1.41 0.66 25.89

Lincoln, Neb. 30 0.67 0.66 2.21 2.90 4.23 3.51 3.54 3.35 2.92 1.94 1.58 0.86 28.37

Norfolk, Neb. 30 0.57 0.76 1.97 2.59 3.92 4.25 3.74 2.80 2.25 1.72 1.44 0.65 26.66

North Platte, Neb. 30 0.39 0.51 1.24 1.97 3.34 3.17 3.17 2.15 1.32 1.24 0.76 0.40 19.66
Bulletin 1724E-302

Page B-7

Normal Monthly Precipitation (Inches)

Normals 1971-2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Omaha Eppley Airport, Neb. 30 0.77 0.80 2.13 2.94 4.44 3.95 3.86 3.21 3.17 2.21 1.82 0.92 30.22

Omaha (North), Neb. 30 0.76 0.77 2.25 3.07 4.57 3.84 3.75 2.93 3.03 2.49 1.67 0.95 30.08

Scottsbluff, Neb. 30 0.54 0.58 1.16 1.79 2.70 2.65 2.13 1.19 1.22 1.01 0.80 0.56 16.33

Valentine, Neb. 30 0.30 0.48 1.11 1.97 3.20 3.01 3.37 2.20 1.61 1.22 0.72 0.33 19.52

Elko, Nev. 30 1.14 0.88 0.98 0.81 1.08 0.67 0.30 0.36 0.68 0.71 1.05 0.93 9.59

Ely, Nev. 30 0.74 0.75 1.05 0.90 1.29 0.66 0.60 0.91 0.94 1.00 0.63 0.50 9.97

Las Vegas, Nev. 30 0.59 0.69 0.59 0.15 0.24 0.08 0.44 0.45 0.31 0.24 0.31 0.40 4.49

Reno, Nev. 30 1.06 1.06 0.86 0.35 0.62 0.47 0.24 0.27 0.45 0.42 0.80 0.88 7.48

Winnemucca, Nev. 30 0.83 0.62 0.86 0.85 1.06 0.69 0.27 0.35 0.53 0.66 0.80 0.81 8.33

Concord, N.H. 30 2.97 2.36 3.04 3.07 3.33 3.10 3.37 3.21 3.16 3.46 3.57 2.96 37.60

Mt. Washington, N.H. 30 8.52 7.33 9.42 8.43 8.21 8.36 8.02 8.08 8.55 7.66 10.49 8.84 101.91

Atlantic City Airport, N.J. 30 3.60 2.85 4.06 3.45 3.38 2.66 3.86 4.32 3.14 2.86 3.26 3.15 40.59

Atlantic City C.O., N.J. 30 3.44 2.88 3.79 3.25 3.16 2.46 3.36 4.16 3.02 2.71 2.96 3.18 38.37

Newark, N.J. 30 3.98 2.96 4.21 3.92 4.46 3.40 4.68 4.02 4.01 3.16 3.88 3.57 46.25

Albuquerque, N.M. 30 0.49 0.44 0.61 0.50 0.60 0.65 1.27 1.73 1.07 1.00 0.62 0.49 9.47

Clayton, N.M. 30 0.30 0.27 0.62 0.99 2.08 2.21 2.81 2.69 1.56 0.74 0.54 0.32 15.13

Roswell, N.M. 30 0.39 0.41 0.35 0.58 1.30 1.62 1.99 2.31 1.98 1.29 0.53 0.59 13.34

Albany, N.Y. 30 2.71 2.27 3.17 3.25 3.67 3.74 3.50 3.68 3.31 3.23 3.31 2.76 38.60

Binghamton, N.Y. 30 2.58 2.46 2.97 3.49 3.55 3.80 3.49 3.35 3.59 3.02 3.32 3.03 38.65

Buffalo, N.Y. 30 3.16 2.42 2.99 3.04 3.35 3.82 3.14 3.87 3.84 3.19 3.92 3.80 40.54

Islip, N.Y. 30 4.27 3.33 4.76 4.13 3.90 3.71 2.93 4.48 3.39 3.63 3.86 4.13 46.52

New York C. Park, N.Y. 30 4.13 3.15 4.37 4.28 4.69 3.84 4.62 4.22 4.23 3.85 4.36 3.95 49.69

New.York (JFK Airport),

N.Y.

30 3.62 2.70 3.78 3.75 4.13 3.59 3.92 3.64 3.50 3.03 3.48 3.31 42.46

New York (LaGuardia 

Airport), N.Y.

30 3.56 2.75 3.93 3.68 4.16 3.57 4.41 4.09 3.77 3.26 3.67 3.51 44.36

Rochester, N.Y. 30 2.34 2.04 2.58 2.75 2.82 3.36 2.93 3.54 3.45 2.60 2.84 2.73 33.98

Syracuse, N.Y. 30 2.60 2.12 3.02 3.39 3.39 3.71 4.02 3.56 4.15 3.20 3.77 3.12 40.05

Asheville, N.C. 30 4.06 3.83 4.59 3.50 4.41 4.38 3.87 4.30 3.72 3.17 3.82 3.39 47.07

Cape Hatteras, N.C. 30 5.84 3.94 4.95 3.29 3.92 3.82 4.95 6.56 5.68 5.31 4.93 4.56 57.75

Charlotte, N.C. 30 4.00 3.55 4.39 2.95 3.66 3.42 3.79 3.72 3.83 3.66 3.36 3.18 43.51

Greensboro/WinstonSalem/High Point, N.C.30 3.54 3.10 3.85 3.43 3.95 3.53 4.44 3.71 4.29 3.27 2.96 3.06 43.14
Bulletin 1724E-302 

Page B-8

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Raleigh, N.C. 30 4.02 3.47 4.03 2.80 3.79 3.42 4.29 3.78 4.26 3.18 2.97 3.04 43.05

Wilmington, N.C. 30 4.52 3.66 4.22 2.94 4.40 5.36 7.62 7.31 6.79 3.21 3.26 3.78 57.07

Bismarck, N.D. 30 0.45 0.51 0.85 1.46 2.22 2.59 2.58 2.15 1.61 1.28 0.70 0.44 16.84

Fargo, N.D. 30 0.76 0.59 1.17 1.37 2.61 3.51 2.88 2.52 2.18 1.97 1.06 0.57 21.19

Grand Forks, N.D. 30 0.68 0.58 0.89 1.23 2.21 3.03 3.06 2.72 1.96 1.70 0.99 0.55 19.60

Williston, N.D. 30 0.54 0.39 0.74 1.05 1.88 2.36 2.28 1.48 1.35 0.87 0.65 0.57 14.16

Akron, Ohio 30 2.49 2.28 3.15 3.39 3.96 3.55 4.02 3.65 3.43 2.53 3.04 2.98 38.47

Cleveland, Ohio 30 2.48 2.29 2.94 3.37 3.50 3.89 3.52 3.69 3.77 2.73 3.38 3.14 38.71

Columbus, Ohio 30 2.53 2.20 2.89 3.25 3.88 4.07 4.61 3.72 2.92 2.31 3.19 2.93 38.52

Dayton, Ohio 30 2.60 2.29 3.29 4.03 4.17 4.21 3.75 3.49 2.65 2.72 3.30 3.08 39.58

Mansfield, Ohio 30 2.63 2.17 3.36 4.17 4.42 4.52 4.22 4.60 3.44 2.68 3.76 3.26 43.24

Toledo, Ohio 30 1.93 1.88 2.62 3.24 3.14 3.80 2.80 3.19 2.84 2.35 2.78 2.64 33.21

Youngstown, Ohio 30 2.34 2.03 3.05 3.33 3.45 3.91 4.10 3.43 3.89 2.46 3.07 2.96 38.02

Oklahoma City, Okla. 30 1.28 1.56 2.90 3.00 5.44 4.63 2.94 2.48 3.98 3.64 2.11 1.89 35.85

Tulsa, Okla. 30 1.60 1.95 3.57 3.95 6.11 4.72 2.96 2.85 4.76 4.05 3.47 2.43 42.42

Astoria, Ore. 30 9.62 7.87 7.37 4.93 3.28 2.57 1.16 1.21 2.61 5.61 10.50 10.40 67.13

Burns, Ore. 30 1.18 1.11 1.24 0.85 1.05 0.66 0.40 0.45 0.50 0.72 1.11 1.30 10.57

Eugene, Ore. 30 7.65 6.35 5.80 3.66 2.66 1.53 0.64 0.99 1.54 3.35 8.44 8.29 50.90

Medford, Ore. 30 2.47 2.10 1.85 1.31 1.21 0.68 0.31 0.52 0.78 1.31 2.93 2.90 18.37

Pendleton, Ore. 30 1.45 1.22 1.26 1.13 1.22 0.78 0.41 0.56 0.63 0.99 1.63 1.48 12.76

Portland, Ore. 30 5.07 4.18 3.71 2.64 2.38 1.59 0.72 0.93 1.65 2.88 5.61 5.71 37.07

Salem, Ore. 30 5.84 5.09 4.17 2.76 2.13 1.45 0.57 0.68 1.43 3.03 6.39 6.46 40.00

Sexton Summit, Ore. 30 4.71 4.29 3.92 2.38 1.35 0.94 0.35 0.61 1.20 2.93 5.32 5.18 33.18

Guam 30 5.58 5.11 4.24 4.16 6.39 6.28 11.66 16.17 13.69 11.88 9.34 6.11 100.61

Johnston Island 30 1.64 1.29 2.01 1.86 1.14 0.87 1.40 2.07 2.46 2.78 4.78 2.70 25.00

Koror, Caroline Islands 30 11.20 9.65 8.79 9.45 11.27 17.54 16.99 14.47 11.65 13.41 11.62 12.33 148.37

Kwajalein, Marshall Islands 30 5.12 3.73 3.82 7.63 8.62 8.86 10.24 10.42 11.82 11.46 10.74 7.94 100.40

Majuro, Marshall Islands 30 8.09 6.86 8.43 11.30 11.53 11.09 12.41 11.95 11.96 13.73 12.81 11.50 131.66

Pago Pago, Amer. Samoa 30 14.02 12.14 11.15 11.16 10.43 5.94 5.76 6.43 7.36 10.03 11.16 13.38 118.96

Pohnpei, Caroline Islands 30 12.52 9.78 13.96 16.94 19.41 17.06 16.72 16.37 14.94 16.30 14.74 15.87 184.61
Bulletin 1724E-302

Page B-9

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Chuuk, E. Caroline Islands 30 8.58 8.77 8.15 10.94 11.29 12.82 12.45 15.09 13.12 10.69 11.09 10.98 133.97

Wake Island 30 1.40 1.89 2.38 2.11 1.70 1.95 3.44 5.62 4.82 4.27 2.78 1.87 34.23

Yap, W. Caroline Islands 30 7.24 5.45 6.14 5.58 8.15 13.46 13.25 14.41 13.53 12.25 8.82 9.34 117.62

Allentown, Pa. 30 3.50 2.75 3.56 3.49 4.47 3.99 4.27 4.35 4.37 3.33 3.70 3.39 45.17

Erie, Pa. 30 2.53 2.28 3.13 3.38 3.34 4.28 3.28 4.21 4.73 3.92 3.96 3.73 42.77

Harrisburg, Pa. 30 3.18 2.88 3.58 3.31 4.60 3.99 3.21 3.24 3.65 3.06 3.53 3.22 41.45

Middletown/Harrisburg Intl

Airport, Pa.

30 3.18 2.88 3.58 3.31 4.60 3.99 3.21 3.24 3.65 3.06 3.53 3.22 41.45

Philadelphia, Pa. 30 3.52 2.74 3.81 3.49 3.88 3.29 4.39 3.82 3.88 2.75 3.16 3.31 42.05

Pittsburgh, Pa. 30 2.70 2.37 3.17 3.01 3.80 4.12 3.96 3.38 3.21 2.25 3.02 2.86 37.85

Avoca, Pa. 30 2.46 2.08 2.69 3.28 3.69 3.97 3.74 3.10 3.86 3.02 3.12 2.55 37.56

Williamsport, Pa. 30 2.85 2.61 3.21 3.49 3.79 4.45 4.08 3.38 3.98 3.19 3.62 2.94 41.59

Block Is., R.I. 30 3.68 3.04 3.99 3.72 3.40 2.77 2.62 3.00 3.19 3.04 3.77 3.57 39.79

Providence, R.I. 30 4.37 3.45 4.43 4.16 3.66 3.38 3.17 3.90 3.70 3.69 4.40 4.14 46.45

Charleston Airport, S.C. 30 4.08 3.08 4.00 2.77 3.67 5.92 6.13 6.91 5.98 3.09 2.66 3.24 51.53

Charleston C.O., S.C. 30 3.62 2.62 3.83 2.44 2.77 4.96 5.50 6.54 6.13 3.02 2.18 2.78 46.39

Columbia, S.C. 30 4.66 3.84 4.59 2.98 3.17 4.99 5.54 5.41 3.94 2.89 2.88 3.38 48.27

Greenville-Spartanburg

Airport, S.C.

30 4.41 4.24 5.31 3.53 4.59 3.92 4.65 4.08 3.96 3.88 3.79 3.86 50.24

Aberdeen, S.D. 30 0.48 0.48 1.34 1.83 2.69 3.49 2.92 2.42 1.81 1.63 0.75 0.38 20.22

Huron, S.D. 30 0.48 0.57 1.67 2.29 3.00 3.28 2.86 2.07 1.80 1.59 0.89 0.39 20.90

Rapid City, S.D. 30 0.37 0.46 1.03 1.86 2.96 2.83 2.03 1.61 1.10 1.37 0.61 0.40 16.64

Sioux Falls, S.D. 30 0.51 0.51 1.81 2.65 3.39 3.49 2.93 3.01 2.58 1.93 1.36 0.52 24.69

Bristol-Johnson CityKingsport, Tenn.30 3.52 3.40 3.91 3.23 4.32 3.89 4.21 3.00 3.08 2.30 3.08 3.39 41.33

Chattanooga, Tenn. 30 5.40 4.85 6.19 4.23 4.28 3.99 4.73 3.59 4.31 3.26 4.88 4.81 54.52

Knoxville, Tenn. 30 4.57 4.01 5.17 3.99 4.68 4.04 4.71 2.89 3.04 2.65 3.98 4.49 48.22

Memphis, Tenn. 30 4.24 4.31 5.58 5.79 5.15 4.30 4.22 3.00 3.31 3.31 5.76 5.68 54.65

Nashville, Tenn. 30 3.97 3.69 4.87 3.93 5.07 4.08 3.77 3.28 3.59 2.87 4.45 4.54 48.11

Oak Ridge, Tenn. 30 5.13 4.50 5.72 4.32 5.14 4.64 5.16 3.39 3.75 3.02 4.86 5.42 55.05

Abilene, Texas 30 0.97 1.13 1.41 1.67 2.83 3.06 1.69 2.63 2.91 2.90 1.30 1.27 23.78

Amarillo, Texas 30 0.63 0.55 1.13 1.33 2.50 3.28 2.68 2.94 1.88 1.50 0.68 0.61 19.71

Austin, Texas 30 1.89 1.99 2.14 2.51 5.03 3.81 1.97 2.31 2.91 3.97 2.68 2.44 33.65
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Page B-10

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Austin/Bergstrom, Texas 30 2.20 1.73 1.98 2.77 5.87 3.38 1.61 1.48 2.63 2.70 2.61 2.39 31.36

Brownsville, Texas 30 1.36 1.18 0.93 1.96 2.48 2.93 1.77 2.99 5.31 3.78 1.75 1.11 27.55

Corpus Christi, Texas 30 1.62 1.84 1.73 2.05 3.48 3.53 2.00 3.54 5.03 3.94 1.74 1.75 32.26

Dallas-Fort Worth, Texas 30 1.90 2.37 3.06 3.20 5.15 3.23 2.12 2.03 2.42 4.11 2.57 2.57 34.73

Dallas-Love Field, Texas 30 1.89 2.31 3.13 3.46 5.30 3.92 2.43 2.17 2.65 4.65 2.61 2.53 37.05

Del Rio, Texas 30 0.57 0.96 0.96 1.71 2.31 2.34 2.02 1.59 2.06 2.00 0.96 0.75 18.23

El Paso, Texas 30 0.45 0.39 0.26 0.23 0.38 0.87 1.49 1.75 1.61 0.81 0.42 0.77 9.43

Galveston, Texas 30 4.08 2.61 2.76 2.56 3.70 4.04 3.45 4.22 5.76 3.49 3.64 3.53 43.84

Houston, Texas 30 3.68 2.98 3.36 3.60 5.15 5.35 3.18 3.83 4.33 4.50 4.19 3.69 47.84

Lubbock, Texas 30 0.50 0.71 0.76 1.29 2.31 2.98 2.13 2.35 2.57 1.70 0.71 0.67 18.69

Midland-Odessa, Texas 30 0.53 0.58 0.42 0.73 1.79 1.71 1.89 1.77 2.31 1.77 0.65 0.65 14.80

Port Arthur, Texas 30 5.69 3.35 3.75 3.84 5.83 6.58 5.23 4.85 6.10 4.67 4.75 5.25 59.89

San Angelo, Texas 30 0.81 1.18 0.99 1.60 3.09 2.52 1.10 2.05 2.95 2.57 1.10 0.94 20.91

San Antonio, Texas 30 1.66 1.75 1.89 2.60 4.72 4.30 2.03 2.57 3.00 3.86 2.58 1.96 32.92

Victoria, Texas 30 2.44 2.04 2.25 2.97 5.12 4.96 2.90 3.05 5.00 4.26 2.64 2.47 40.10

Waco, Texas 30 1.90 2.43 2.48 2.99 4.46 3.08 2.23 1.85 2.88 3.67 2.61 2.76 33.34

Wichita Falls, Texas 30 1.12 1.57 2.27 2.62 3.92 3.69 1.58 2.38 3.19 3.11 1.68 1.68 28.83

Milford, Utah 30 0.73 0.77 1.21 0.99 0.94 0.44 0.76 1.04 0.92 1.12 0.77 0.58 10.27

Salt Lake City, Utah 30 1.37 1.33 1.91 2.02 2.09 0.77 0.72 0.76 1.33 1.57 1.40 1.23 16.50

Burlington, Vt. 30 2.22 1.67 2.32 2.88 3.32 3.43 3.97 4.01 3.83 3.12 3.06 2.22 36.05

Lynchburg, Va. 30 3.54 3.10 3.83 3.46 4.11 3.79 4.39 3.41 3.88 3.39 3.18 3.23 43.31

Norfolk, Va. 30 3.93 3.34 4.08 3.38 3.74 3.77 5.17 4.79 4.06 3.47 2.98 3.03 45.74

Richmond, Va. 30 3.55 2.98 4.09 3.18 3.95 3.54 4.67 4.18 3.98 3.60 3.06 3.12 43.91

Roanoke, Va. 30 3.23 3.08 3.84 3.61 4.24 3.68 4.00 3.74 3.85 3.15 3.21 2.86 42.49

Olympia, Wash. 30 7.54 6.17 5.29 3.58 2.27 1.78 0.82 1.10 2.03 4.19 8.13 7.89 50.79

Quillayute, Wash. 30 13.65 12.35 10.98 7.44 5.51 3.50 2.34 2.67 4.15 9.81 14.82 14.50 101.72

Seattle C.O., Wash. 30 5.24 4.09 3.92 2.75 2.03 1.55 0.93 1.16 1.61 3.24 5.67 6.06 38.25

Seattle Sea-Tac Ap, Wash. 30 5.13 4.18 3.75 2.59 1.77 1.49 0.79 1.02 1.63 3.19 5.90 5.62 37.07

Spokane, Wash. 30 1.82 1.51 1.53 1.28 1.60 1.18 0.76 0.68 0.76 1.06 2.24 2.25 16.67

Walla Walla, Wash. 30 2.25 1.97 2.20 1.83 1.95 1.15 0.73 0.84 0.83 1.77 2.85 2.51 20.88
Bulletin 1724E-302

Page B-11

Normal Monthly Precipitation (Inches)

Normals 1971–2000 Yrs Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. Ann.

Yakima, Wash. 30 1.17 0.80 0.70 0.53 0.51 0.62 0.22 0.36 0.39 0.53 1.05 1.38 8.26

San Juan, P.R. 30 3.02 2.30 2.14 3.71 5.29 3.52 4.16 5.22 5.60 5.06 6.17 4.57 50.76

Beckley, W.Va. 30 3.23 2.96 3.63 3.42 4.39 3.92 4.78 3.45 3.23 2.64 2.88 3.09 41.63

Charleston, W.Va. 30 3.25 3.19 3.90 3.25 4.30 4.09 4.86 4.11 3.45 2.67 3.66 3.32 44.05

Elkins, W.Va. 30 3.43 3.20 3.92 3.53 4.77 4.61 4.83 4.26 3.82 2.86 3.42 3.44 46.11

Huntington, W.Va. 30 3.21 3.09 3.83 3.33 4.41 3.88 4.46 3.88 2.80 2.73 3.32 3.37 42.31

Green Bay, Wis. 30 1.21 1.01 2.06 2.56 2.75 3.43 3.44 3.77 3.11 2.17 2.27 1.41 29.19

LaCrosse, Wis. 30 1.19 0.99 2.00 3.38 3.38 4.00 4.25 4.28 3.40 2.16 2.10 1.23 32.36

Madison, Wis. 30 1.25 1.28 2.28 3.35 3.25 4.05 3.93 4.33 3.08 2.18 2.31 1.66 32.95

Milwaukee, Wis. 30 1.85 1.65 2.59 3.78 3.06 3.56 3.58 4.03 3.30 2.49 2.70 2.22 34.81

Casper, Wyo. 30 0.58 0.64 0.90 1.52 2.38 1.43 1.29 0.73 0.98 1.14 0.82 0.62 13.03

Cheyenne, Wyo. 30 0.45 0.44 1.05 1.55 2.48 2.12 2.26 1.82 1.43 0.75 0.64 0.46 15.45

Lander, Wyo. 30 0.52 0.54 1.24 2.07 2.38 1.15 0.84 0.57 1.14 1.37 0.99 0.61 13.42

Sheridan, Wyo. 30 0.77 0.57 1.00 1.77 2.41 2.02 1.11 0.80 1.38 1.41 0.80 0.68 14.72
Bulletin 1724E-302 

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BLANK PAGE
Bulletin 1724E-302

Page C-1

APPENDIX C

SPCC TYPICAL EXAMPLE

Typical Example: The following SPCC plan was created as an illustration for instructional 

purposes. The oil retention method and cleanup procedures used in this plan should not be 

construed as the best or only methods available but are intended to illustrate the engineering 

decisions that must be made for each electrical facility.
Bulletin 1724E-302

Page C-2

BLANK PAGE
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Page C-3

OIL SPILL PREVENTION, CONTROL, AND 

COUNTERMEASURES PLAN

FOR

(NAME OF SUBSTATION OR FACILITY)

Prepared by: 

(PREPARER) 

(TITLE)

for

(NAME OF COOPERATIVE) 

(ADDRESS)

(CITY, STATE, ZIP CODE)

TEL: (xxx) xxx-xxxx 

FAX: (xxx) xxx-xxxx
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Page C-4

OIL SPILL PREVENTION CONTROL AND COUNTERMEASURES PLAN 

TABLE OF CONTENTS

Required Plan Elements Listed in 40 CFR Part 112 C-4

A. NAME AND TYPE OF FACILITY C-5

B. LOCATION OF FACILITY C-5

C. DATE OF INITIAL OPERATION C-6

D. IDENTIFICATION OF INDIVIDUAL RESPONSIBLE FOR OIL SPILL C-6 

PREVENTION

E. MANAGEMENT APPROVAL C-6

F. P.E. CERTIFICATION C-7

G. RECORD OF PLAN REVIEWS C-7

H. RECORD OF AMENDMENTS AND REVISIONS TO SPCC PLAN C-8

I. OIL SPILL HISTORY C-8

J. FACILITY’S CONFORMANCE PLAN AND ANALYSIS C-8

K. REPORTING AND NOTIFICATION C-9

L. GOVERNMENT AGENCIES TO BE NOTIFIED C-9

M. SPILL RESPONSE CONTRACTOR INFORMATION C-10

Forms: Notification Form C-11

Description of Spill Event Form C-12
Bulletin 1724E-302

Page C-5

OIL SPILL PREVENTION CONTROL AND COUNTERMEASURES PLAN

Prelude—Required Plan Elements Listed in 40 CFR Part 112

A. Name and Type of Facility

Facility Name:

Facility Type:

Address:

Phone at site: 

Phone at nearest manned station: Location:

Total oil volume contained on-site: 

Volume in largest single container or piece of equipment: 

Drawing of Facility Attached: Drawing No. Date

Oil Containing Equipment Type of Oil Volume PCB Content (ppm)

(55 gallons or more) (gallons) if present

This facility is normally unmanned but is visited on a regular basis—at least once a 

month. The facility is fenced and locked during unattended hours. Facility lighting is 

adequate and is or is not on all night. Past spills have or have not 

occurred at this facility. If spills have occurred, additional information on past spills is 

provided in the Appendix of this plan.

B. Location of Facility

The facility is located in , in County, 

in the quarter of the quarter of Section , in Township 

Range .
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Page C-6

C. Date of Initial Operation

This facility began operation on .

D. Identification of Responsible Individual for Oil Spill Prevention

The responsible individual for thisfacility is: Name:

Title:

Phone:

E. Management Approval

This SPCC Plan has been reviewed by me and will be implemented as herein described. 

Company resources, including manpower, equipment, and materials necessary to contain, 

control, and remove any harmful quantities of oil spilled will be obtained.

Name:

Title:

Signature

Date Signed:
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Page C-7

F. P.E. Certification

I hereby certify that I or my agent have visited and examined the facility known herein as

and that I am familiar with the provisions of 40 CFR Part 112—Oil Pollution Prevention.

I attest that this SPCC Plan (1) has been prepared in accordance with good engineering 

practices, including consideration of applicable industry standards; (2) is adequate forthis 

facility; and (3) that procedures for required testing and inspections have been 

established.

Printed Name of Registered Professional Engineer

Signature of Registered Professional Engineer

Date Signed Registration No. State

G. Record of Plan Reviews

(Required at least once every five years or when there has been a significant change to the 

facility.)

I have completed review and evaluation of this SPCC Plan on the following date:

Date Result of Review

, and I will will not amend the plan as a result.

(signature of reviewer)

, and I will will not amend the plan as a result.

(signature of reviewer)

, and I will will not amend the plan as a result.

(signature of reviewer)
Bulletin 1724E-302

Page C-8

, and I will will not amend the plan as a result.

(signature of reviewer)

, and I will will not amend the plan as a result.

(signature of reviewer)

, and I will will not amend the plan as a result.

(signature of reviewer)

H. Record of Amendments and Revisions to SPCC Plan

Date Page(s) Subject/Reason Initials

I. Oil Spill History

Since the construction of this substation in , there have been oil spill 

incident(s). Details of these spills, if any, are included in the Appendix to this SPCCPlan.

J. Facility’s Conformance Plan and Analysis

In the event of an oil spill at this facility under normal weather conditions, the maximum 

potential spill of gallons of oil (from the single largest piece of oil-filled 

equipment) would be contained within the station’s gravel bed and/or immediate vicinity. 

During periods of heavy rainfall, oil and water would flow

Four to six inches of rock gravel surfacing are normally required in all electrical facility 

yards. This design feature benefits the operation and maintenance of the facility by 

providing proper site drainage, reducing step and touch potentials during short circuit 

faults, eliminating weed growth, improving yard working conditions, and enhancing 

station aesthetics. In addition to these advantages, this gravel bed will aid in fire control
Bulletin 1724E-302

Page C-9

and in reducing potential oil spill cleanup costs and penalties that may arise from Federal 

and State environmental laws and regulations.

The yard surfacing at this substation serves as the secondary method of containment. It 

limits the flow of oil in the event the primary method—the tank—fails. It is unlikely that 

a spill would migrate beyond the yard surfacing. As shown on the grading plan, the 

surfaced area surrounds the largest piece of oil-filled equipment by a radius of at least

feet.

Within this radius, the substation itself has been graded to be essentially flat, allowing 

only enough grade for surface water runoff. Although the yard surfacing and grading 

allow easy runoff of water (low viscosity), they act to check the flow and spread of oil 

(high viscosity). See Section II.C.

Any equipment necessary for cleanup is kept at —a permanently manned 

facility located at , approximately road miles from this facility. The 

personnel at located in would be responsible for the cleanup. The station 

is located at . Phone number: .

While the station is the primary location of cleanup equipment, oil spill cleanup 

equipment also is located at (1) ; (2) ; and (3) .

K. Reporting and Notification

The Spill Response Coordinator for this site is: 

Name:

Work Phone:

Home Phone:

Cell Phone:

Alternate coordinators are:

Name:

Work Phone:

Home Phone:

Cell Phone:

Name:

Work Phone:

Home Phone:

Cell Phone:

L. Government Agencies to be Notified

If an oil release to water is imminent or has occurred, the coordinator will notify (the

designated utility department person or persons—use title). He/she or a representative of 

this department will notify the appropriate local, State, and Federal agencies. If 

representatives of the above department cannot be reached, notification to outside 

agencies will be made by the coordinator.
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Page C-10

The following agencies should be contacted if a spill has reached surface water:

County Office of Emergency Services: 

State Department of Environmental Quality: 

National Response Center (U.S. Coast Guard): Phone:

Downstream Water Suppliers:

City: Company: Phone:

City: Company: Phone:

Information on the spill—see Notification Form at the end of this section—should be at 

hand when these calls are made.

M. Spill Response Contractor Information

Spill Response Contractor: Spill Responders, Inc. 

Phone:
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Page C-11

Notification Form

Items 1–6 should be completed before contacting government agencies. The agencies need this 

information at a minimum to access the seriousness of the spill.

Date:

1. Name of Company

2. Date of Spill

3. Time of Spill (est. known ) Time Spill Detected (est. known )

4. Location of Spill

5. Name of Receiving Body of Water

6. Material and Amount Spilled Gallons of 

7. Probable Source orCause

8. Actions Initiated to Contain orCleanup

9. Person to Contact on Scene

Name Phone

10. Report Initiated by

Name

Title

Phone

11. Government Agency Official(s) Notified

Name Date Time

Title

Phone
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Page C-12

Description of Spill Event Form

Date:

1. *Facility name and

location

2. *Date when facility began

operation

3. *Owner and operator at time of

spill

4. *Name and address of registered agent of owner or

operator

5. *Maximum storage or handling facility at time of

spill

6. *Normal daily

throughput

7. *Type of oil or fluid that spilled *Volume 

released

8. *Likely cause of

release

9. *Equipment

involved

10. *Corrective actions and/or countermeasures taken to stop or mitigate 

discharge

11. *Any changes in equipment or procedures made to prevent similar spills in the 

future:
Bulletin 1724E-302

12. Date of spill Was it raining at time ofspill?

Page C-13

13. Was water or foam used for fire suppression at time of spill?

14. Estimated quantity reaching waterbody

waterbody

Name of

15. Cleanup measures used onsite

16. Volume of soil removed Volume of oil removed

17. Cleanup measures used for

waterbody

18. Observed environmental effects, if any, after

cleanup

*Required information under Sec. 112.4 if one spill event of 1,000 gallons or greater of oil 

occurs or two spills within a consecutive 12-month period occur. Other information could be 

used by utility to improve spill prevention and control procedures. If a spill meeting the 

above criteria occurs, required information and copy of SPCC Plan must be submitted to 

EPA Regional Administrator within 60 days of applicable spill and a copy sent to the

Department of Environmental Quality.
Bulletin 1724E-302

Page C-14

BLANK PAGE
S ou rc e: USG S Quad rangle M ap: Gidd in gs , Texa s, L as t Edited 1988

Legend N D irec tion of Flow

Loca tion of S ubs tation

0 M il e 1 Mile

0 2 0 0 0 F e e t 4000 Feet

G raphic S cale

APPENDIX D 

OPTIONAL SPCC WALL PLAN

Bulletin 1724E-302

D-1

Spill Prevention, Control and Counterm easure Plan G 

iddings Substation

Figure 1 . G iddings S ubstation & S pill Flow Direction

1.0 SITE INFORMATION

Em ergency Spill R esponse Procedures

N otify:

HAZMAT REPO RTABLE

N otify:

NO N-REPO RTABLE

N otify:

2.0 S PILL CONTACTS

Figure 2. G iddings S ubstation Layout

TABL E 1

EQUIPM ENT INF ORM ATION

1 . 911 if there is fire o r injuries 2. SOCC (512- 482 -6220)

3. TOCC (512-369 -8911)

4 . Superv isor

Report:

1 . Your name and call bac k number 2 . 

The exact location and nature of the inc ident

3 . Th e nu mber of pers onnel affected and any pertinent information

1. Superv isor 2. . Tran smission Services

Env iro nmental (See Section 2.0 for list of phone num bers)

3 . TOCC (512-369-8911)

Report:

1 . Your n ame and call bac k number 2 . 

Th e ex act location and nature of the incident 3. . Th e number of pers onnel affected and a ny p ertinent information

Tran smission Servic es Env ironme ntal if 

spill is on soil (See Section 2 .0 for list of p hone num bers)

Report:

Not nec essary fo r non-rep ortable spills

A rea Super visors

East Area Sup ervisor 

West Area Sup ervisor

Cen tral A re a Su pe rvisor 

T ra nsmissio n Serv ic es -

Env ir onmental

W aste C oordinator

E nvironme ntal E ngineer

E nvironme ntal C oordinator

T ra nsmissio n Serv ic es - Safety

Safety Re presen tative 

Safety Re presen tative 

Safety Re presen tative 

Customer Co ntacts 

C ity of G iddings

B luebon net Electric Co op.

Office

(512) 3 58-6033

(512) 3 56-5281

(512) 4 82-6365

Office

(512) 3 56-6039

(512) 3 56-6481

(512) 4 82-6261

Office

(512) 3 56-6442

(512) 3 56-6090

(512) 4 82-6238

Office

(979) 5 42-2311

(800) 8 42-7708

M obile

(512) 9 23-1083

(512) 9 65-3213

(512) 9 13-5552

M obile

(512) 9 24-9609

(512) 9 23-7815

(512) 9 24-8435

M obile

(512) 9 23-4325

(512) 5 87-3633

(512) 9 21-0771

M obile

Pa ger

(512) 2 22-2653

(512) 2 22-9400

(512) 2 22-2654

Pa ger 

N one 

N one 

N one 

Pa ger 

N one 

N one

(512) 2 22-3151

Pa ger

(512) 5 17-7017

Priority Actions:

1. . Designate the On site Commander (high est rank ing pers on o n site).

2. . Assess all ha zards, particularly

electrica l hazards, fires , an d ha zardous materials (including PCBs) releas es by f ire or disch arge to s oil or water.

3. Enter the area wearing PPE only when safety hazards have been contro lled a nd s top the spill if it can be d one 

safely . O therwise, wa it for Hazmat 

Contractor to arrive.

Priority Actions:

1 . Assess all hazards, pa rticularly

electrical ha zards, f ires, and hazardous 

materials (including PCBs) releases by fire 

or d isc harge to soil or water.

2. Enter the area wearing PPE only when safety hazards have be en co ntrolled

and stop the spill if it can be done 

safely.

3 . Barrica de the area (or us e yellow warning tape) and lim it acces s to 

authorized pers onnel wearing

Priority Actions:

Cover the affecte d area with sorbents

or an approved bio-rem ediation solution.

If a fter no r m a l busine ss ho ur s , ca ll E nv iro nm ental Spill Phone

If unable to co ntact abov e personne l, c all TOCC 

L CR A Co rpor ate Sa fe ty & E nv ironmental

L CR A Co rpor ate Co mm unications

(512) 3 69-8911

(512) 473-3 200

E xtension 7745

(512) 4 73-4032

4 . Barricade the area (or us e yellow 

warning tape ) and limit acce ss to 

authoriz ed person el wearing

appropriate PPE.

app rop ria te PPE.

3 .0 A GE NC Y & OTHE R CONTACTS 5 . Rema in at scene until relieved.

Entity

L oc al Fire Department - Lee C ou nty Sheriff

L oca l L aw Enforc eme nt Agency - G id ding s Po lice D ep artment

L oc al E mergency Pla nning Committee - M r. L .E. "B uster" Dussetschleger 

T exas C ommission on E nv ironmental Q uality, EmergencyResponse

N atio na l Re sp on se Center 

E PA R eg io n VI H otline

H AZMA T Co ntractors - HA ZM AT C on tracto rs - Sta ffed 24 hours a day and 

o n-ca ll o n an a ro un d th e cloc k ba sis. In the e ve nt that HAZMAT contractor 

service s are requ ired , co ntact LC RA T ransmissio n Serv ices E nvironmental. 

C on tact E nvironme ntal personn el during norm al business hours and the

E nv iron mental Spill Pho ne a fter n ormal bu siness hours.

Ho spital - L a Gran ge Fay ette M em orial

5 43 North Jac kso n, La Gra nge, T exa s 7 894 5-2040

D ire ctio ns to Ho spital from Substation: Fro m th e su bs ta tion g o west on 

U .S . 29 0 to U .S . 77 . Tak e U. S. 7 7 so uth to L a Gran ge. In La Grange from 

U .S. 77 g o east on E. R oltsch L n. Go south on N. Jackson St., hospital is at 

5 43 North Jackso n St.

Telepho ne #

911

911

(979) 5 42-2800

(512) 4 63-7727

(800) 4 24-8802

(866) 3 72-7745

See Sec tion 2.0 for spill 

contact nu mbers.

(979) 9 68-3166

Rem oval of Contaminated Media: Tran smission Services Enviro nme ntal will 

colle ct sam ple s and arrange

d isp osal a t an authorized disposal

facility.

Follow up:

Tran smission Services Enviro nme ntal

R em oval of C ontaminated Media: 1. . Clea n up all visible trac es of

c onta mination on hard surfaces. 

Excavate contamin ated soil and 

collec t contaminated water. 2. . Plac e the contam ina ted media in

containers or in a contro lled staging 

area. 3. . Tran smission Servic es Environmental will c ollect samples and arrange disposal at a n au thorized dis posal 

facility.

Follow up:

T ransmission Servic es Env ironmental

R em oval of C ontaminated Media: 1 . Clea n u p a ll vis ible trac es of contamination on hard surfa ces.

Excavate contamin ated soil, if 

necessary 2 . Place the con tam inated media in de signated containers. 3 . Contact Wa ste Coord inator for 

waste man agem ent instructions 

(512-356- 6039).

Follow up:

Not nec ess ary for non-reportable spills.

4 .0 SPILL REP ORTING RE QUIREMENTS

REPORTABL E QUANTITIES AND GOVT. AGENCY CONTACTS

will complete Telephone Spill

Report and will contact a ppropriate 

regulatory agencies.

will complete Telephone Spill Report c 

ontact appro priate regulatory

a gencies, if necessary. Substance

PCBs 

PCBs

Oil 

Oil

R efined Petroleum 

Pro du cts (fue l, motor

o il, etc.) 

Min eral O il

Untested Mine ral 

Oil 2

Oil

Qua ntity 

1 pound 

10 pounds

A ny a mount that 

c auses sheen

A ny amount

2 5 ga llons 

2 10 gallons

2 70 gallons

5 00 gallons

Media 

All 

All

Water 

Wetla nd s;

E nv iron mentally 

sen sitive areas

Land

Land

Land 

Land

A gency 1

NRC & T CEQ 

EPA VI

NRC & T CEQ

N RC , TN RT & TCEQ

TCEQ

TCEQ

NRC 

TNRT

5.0 P ROFESS ION AL ENG INEER'S 

C ERTIFICA TION

T his SPCC Plan ha s been p re pa re d un de r th e su pe rv is io n of a registered professional

e ng in ee r. Do cu mentatio n pe rtaining to certificatio n of this SPCC Pla n by a registered 

Pro fessio nal En gineer p ursu an t to 4 0 CFR § 1 12 .3 (d ) is available at the LCRA

T ransmission Se rv ices D alchau Service C en te r loca ted at 3505 Montopolis Drive in Austin, Texa s.

6.0 W RITTEN C OM MITM ENT OF MANPOWER, 

EQU IPMENT, AN D MA TERIALS

Pursu an t to 4 0 CFR §1 12 .7 (d )(2), LC RA h as p re pa re d a written co mmitment o f manpower, equipment, and 

materials require d to expeditiously c ontrol and remov e any quantity o f oil discharged that may be harmful. 

D ocumen ta tion p ertain in g to this writte n co mmitment is av aila ble at the L CR A Tran smission Services

D alchau Service C ente r locate d at 3505 Montopolis D rive in Austin, Texas.

1 Agen cies: E PA V I = Environm enta l Protec tion Age ncy, Reg ion 6; N RC = Nationa l Re spon se C enter; T CEQ = Te xas 

C omm ission on En vironm ental Qua lity; TNR T = Te xas Na tural Resource Trustees.

2 Assume s that th e spill c ontain s PCB Con tam ina ted oil (>50 PPM and <499 PPM)

T his drawing has been rep rodu ced for the purp ose of S PCC plan pre para tion and is to b e us ed s olely fo r this purpose.

NO Is the spill greate r than one gallon of oil or 

any am ount causing a sheen on

water?

YES

Spill C lassification

YES

REPO RTABLE: A spill, leak, or release of 

non-P CB oil that is greater

tha n one gallon on land or in 

any am ount that causes an

oil she en on the surface in a w 

ater body or along its

shorelines.

Can the spill be quickly

controlled or c onta ined at the 

tim e of spill orrelease?

NO

HAZMAT:

A reporta ble spill or release of 

oil into the env ironm ent that 

cannot be quickly

controlled or conta ined a t the 

1 .1 Location and Directions tim e of the s pill or release. T his Sp ill Prev en tion , Co ntro l an d Co un te rmeasu re (SPCC ) Plan p re sents th e ba sic information to be u 

sed in responding to oil spills at the LCRA Giddings Substation. T he fac ility is located in Lee

C ou nty (Fig ure 1). T he fac ility is currently in use as a n elec tric al sub statio n an d there are no plans to

chang e its cu rren t use in the near future.

T his plan add re sses LCR A-ow ned eq uipmen t. Cu stomer-o wn ed equ ip ment that is subject to SPCC

reg ulatio ns is id en tified in th is p la n an d asso ciated d ocumen ta tion . SPC C co mp liance with regard to 

custo me r- ow ned eq uipmen t is the custo me r's responsibility.

D irections to the facility: From th e inte rsection of Hwy 29 0 a nd Hwy 77 in Giddings, go approxima te 

ly 0.0 8 miles we st, su bsta tion is on the left.

911 A dd ress: 1 398 W . Au stin St., Giddings, T X 7 8942

F acility phon e nu mber: (979) 5 42-2751

1 .2 Spill Pa th Pre diction

D ra inage from the substation flows 1/8 miles southwest into an adjac ent stock ta nk. If overflow

o ccurred, flo w wo uld trav el 1 1⁄4 miles sou th west into Wo lf B ra nc h Creek. W olf Branch Creek feeds

into Ra bb s Cree k an d me rg es w ith th e Co lo ra do R iv er near La Grange, TX. Figu res 1 and 2 sho w the 

flo w pa th d ir ec tion s in the event o f a spill.

G iddings Substation

L egend 

Drainage Flow Dir ection

 Loc atio n of E quip ment 

Drainage Co ntro l Berm

* E quipme nt own ed by City o f G idd ing s,

w ho has res po ns ib ilit y for complying

w ith SP CC req uire me nts and SPCC 

related s pill res po ns e re ga rd ing this 

e quip ment.

NON-REPORTABLE:

A spill, leak or rele as e of non- P 

CB oil tha t is less than one

gallon on land, asphalt, or

other hard surfac e. If P 

CB concentration is

unk nown or at least 50 ppm , 

call Transm is sion Services E 

nvironm ental im m ediately.
Bulletin 1724E-302

D-2

BLANK PAGE
Bulletin 1724E-302

E-1

APPENDIX E 

CONTRIBUTORS

The following members of the National Rural Electric Cooperative Association (NRECA) 

Transmission & Distribution (T&D) Substation Subcommittee provided invaluable assistance in 

preparing this document.

Dan Geiger, Heartland Engineering Services, Rockford, MN 

Bil Kahanek, Lower Colorado River Authority, Austin, TX 

Ken Malone, Middle Tennessee EMC, Murfreesboro, TN 

Allen Xi, Burns & McDonnell, Houston, TX

Paul Rupard, East Kentucky Power Cooperative, Winchester, KY 

Thomas Barnette, Berkeley Electric Cooperative, Moncks Corner, SC 

Tom Myers, Berkeley Electric Cooperative, Moncks Corner, SC

Mike Eskandary, Rural Development, Utilities Programs, Washington, D.C. 

Norris Nicholson, Rural Development, Utilities Programs, Washington, D.C. 

Mike Pehosh, NRECA, Arlington, VA

James Stine, NRECA, Arlington, VA 

Bob Saint, NRECA, Arlington, VA

Kevin White, Northeast Missouri Electric Power, Palmyra, Missouri 

Mike Avant, Garkane Energy Cooperative, Loa, UT

Kenny Adams, SGS Witter Inc., Albuquerque, NM

Jim Bardwell, SGS Witter Inc., Albuquerque, NM

Shawn Higbe, McCall-Thomas Engineering, Inc., Orangeburg, SC 

Kevin Seesholtz, South Central Power Co. Canal Winchester, OH 

Mike Garland, Jr., Mountain View Electric Assn., Limon, CO 

Kevin Groves, West Plains Engineering Inc., West Plains, MO 

Jared Newton, United Services Group, Elk River, MN

Kirk Powell, Burns & McDonnell, Houston, TX