United States Environmental Protection Agency Office of Water (WH-595) September 1991 832S91100 &EPA Hydrogen Suitide Corrosion: Its Consequences, Detection and Control &*&;&-.. /*f .1 ------- Acknowledgements Material in this document was prepared under EPA ,Contract 68-C8-0023 by HydroQual, Inc. and J.M., Smith & Associates, Consulting Engineers. Principal authors were Robert P.G. Bowker and Gerald A. .Audibert of J.M. Smith & Associates. Technical review and graphical support was provided by Eugene Donovan and the staff at HydroQual, Inc.. EPA staff who provided technical guidance and review include Irene Suzukida, formerly with EPA's Office of Water, Office of Wastewater Enforcement and Compliance, Lam Lim with the Office of Wastewater Enforcement and Compliance, and Randy Revetta with EPA's Center for Environmental Research Information. The information in this document is a summary of the larger, detailed report entitled, " Detection, Control, and Correction of Hydrogen Sulfide Corrosion in Existing Wastewater Systems." Mention of trade names or commercial products does not constitute endorsement by EPA. Omission of certain products from this document does not reflect a position of EPA regarding product effectiveness or applicability. Cover: Unexpected Street Collapse Due to Sewer Corrosion (photo courtesy of Instituform, Inc.) ------- Introduction Is undetected hydroge.n sulfide corrosion causing steady deterioration of your sewerage system? Will you be faced with costly sewer replacement or reha- bilitation projects in ten or twenty years even though the design life of the system may be fifty years or more? Unfortunately, many municipalities do not . recognize corrosion problems until extensive damage has occurred, such as a sewer collapse or equipment failure. The cost to repair or replace pipes, equipment and structures deteriorated by hydrogen sulfide corrosion may exceed by many times the cost to control the corrosion and avoid infrastructure damage. Nationally, the cost to repair corrosion damage by hydrogen sulfide is in the billions of dollars, and many communities will spend millions of dollars in the next few years to correct corrosion problems. Severe corrosion experienced in Los Angeles County and municipalities throughout the United States prompted Congress to direct the U.S." . Environmental Protection Agency to conduct a national assessment of the problem, resulting in the Report to Congress: Hydrogen Sulfide Corrosion in Wastemater Collection and Treatment Systems in 1990. As a follow-up to that work, 'a technical handbook was prepared entitled Detection, Control, and Correction of Hydrogen Sulfide Corrosion in Existing Wastewater Systems, This brochure provides an overview of that document. Sewer replacement can be a very costly proposition, especially in urban areas. ------- .Chapter? What Are The Implications Of Hydrogen Sulfide Corrosion? Consequences of H^S Corrosion The presence of hydrogen sulfide can lead to rapid and extensive damage to concrete and metals used in the construction of wastewater collection and treatment systems. Sewers,, pump stations, and 'treatment facilities, including electrical controls, instrumentation, process equipment, tankage and ventilation systems can be affected. In the U.S. the problem'is not limited to warm climates, and it is rarely brought to the attention of the public until a catastrophic event occurs, such as a sewer collapse resulting in street cave-in. Hydrogen sulfide corrosion in wastewater systems often results in costly, premature replacement or rehabilitation of systems used in the transport and treatment of wastewater. Sewers designed to last 50 to, 100 years have failed due to hydrogen sulfide corrosion in as little as 10 to 20 years. Electrical and mechanical equipment with an expected source life of 20 years has required replacement in as little as five years. Social and Economic Costs / - The economic implications of hydrogen sulfide corrosion are staggering. A 1989 study conducted by the Sanitation Districts of Los Angeles County estimated that over $-150 million is currently needed to repair or replace 25 miles of extensively damaged -sewers. An additional $35 million may also be required to repair or replace 16 miles with moderate corrosion unless it can be controlled. The report further states that if the additional 500 miles of sewers were to be severely damaged by corrosion, their replacement'cost would be $1 billion. Similarly, the City of Houston currently estimates the cost of its sewer rehabilitation program at $477 million. Seventy percent of the problem is attributed to hydrogen sulfide corrosion. On a national, scale,. sewer rehabilitation alone is estimated to cost $6 billion. In addition to djrect costs associated with planned sewer repairs and replacement, unplanned replacement costs resulting from sewer collapse and the increase in preventative maintenance costs are similarly very high. It is clearly evident that a means, to detect, control and correct hydrogen sulfide corrosion in existing wastewater systems is the preferred alternative to premature replacement of system components. Hydrogen sulfide is an odorous, toxic gas. Each year, deaths result from exposure of workers to hydrogen sulfide gas in confined spaces. Odor complaints result from neighbors living near wastewater handling systems who are exposed to low levels of the gas. Although difficult to quantify-, these costs are substantial. ------- Chapter 3 What Causes Hydrogen Sulfide Corrosion? Mechanism of Sulfide Corrosion Hydrogen sulfide corrosion can occur by two mechanisms: 1) acid attack resulting from the biological conversion of hydrogen sulfide gas to sulfuric acid in the presence of moisture, and 2) direct chemical reaction with metals such as copper, iron .and silver with hydrogen sulfide gas. The first mechanism is the one which is the principal cause of internal sewer corrosion, while the second can cause premature failure of electrical and instrumentation systems, and mechanical equipment used in the transport and treatment of wastewater. The principal mechanism by which sulfide generation and corrosion occurs in sewers is illustrated in Figure 1, while Figure 2 depicts the process by which hydrogen sulfide corrosion causes sewer failure. > SO Figure!. Mechanism of Sulfide Generation and Corrosion in Sewers anaerobic r bacteria Anaerobic Slime Layer (typically 1mm thick) (A) Sulfate is biologicajly reduced to sulfide in the anaerobic slime layer on the submerged pipe wall. Condensate; Location of H ^.Oxidizing Bacteria Anaerpbic.Slime Layer (typically 1mm thick) (B) H2S formed in the wastewater is released from solution as a gas and enters the sewer atmosphere H S +2O aerobic 2 bacteria Corroded Moist Pipe Surface (C) H2S is oxidized to sulfuric acid by aerobic Thiobacillus bacteria living on moist, non-submerged surfaces. Acid attacks concrete, causing corrosion ------- Street ' -" ''-' -"-'o O ' Backfill (gravel.soil) ' (A) Corrosion reduces structural integrity of pipe crown .;-.-. ^> o.'^.''-. 'Accumulation of Debris (B) Crown collapses and'void forms from backfill washing into sewer (C) Backfill continues to wash into sewer eventually leading to sewer blockage - and/or street collapse B Factors Affecting Corrosion of Sewers Four conditions must be-satisfied in order for hydrpgen sulfide corrosion to take place in sewers: 1. Absence o'r very low levels of dissolved oxygen in the wastewater . 2. Generation of sulfide in the wastewater and release of hydrogen sulfide-gas from solution ., ' 3. Presence pf moisture on the material to be corroded 4: Material which is subject to cofrosion by sulfuric acid attack. Dissolved oxygen depletion is affected by sewage velocity, wastewater characteristics, detention time ,and temperature. Whe'n the dissolved oxygen is depleted, the rate of sulfide generation is controlled by the concentration of organic materials, nutrients and temperature. The subsequent release of hydrogen sulfide gas to the atmosphere of a sewer, wet well or other confined space is dependent upon the sewage pH, extent of turbulence and wastewater temperature. Finally, the rate of corrosion is governed by the temperature, the quantity of hydrogen,sulfide available to be biologically converted to sulfuric acid, and the material's inherent resistance to acid attack. In wastewater treatment plants, damage.can be caused by .two mechanisms: 1) acid attack as described above, and 2) direct attack of metals such as iron and copper by hydrogen sulfide. N Figure 2. Process of Sewer Failure Due To Hydrogen Sulfide Corrosion ------- Chapter 4 How Do I Know If A Corrosion Problem Exists? It is essential that corrosion problems be identified early while the c'orrosion can still be controlled. Otherwise you may be faced with the high cost of sewer replacement or rehabilitation, and/or premature replacement or reconstruction of mechanical equipment, structures and electrical controls used in wastewater pumping stations and treatment plants. Corrosion detection and monitoring can be conducted economically, and the cost of such programs is only a small fraction of the cost to repair damage caused by hydrogen sulfide corrosion. Figure 3 shows a flow diagram of the basic steps involved in identifying existing or potential corrosion problems. Identifying Potential Problem Areas Hydrogen sulfide corrosion can be detected at many locations in wastewater collection and treatment systems. Areas where corrosion is likely to be found include the following: Sewers with flat slopes, low wastewater velocities, and long detention times Manholes and junction chambers' Force main discharges Areas of high turbulence Pump station wet wells . Treatment facility headworks Primary clarifier effluent channels Sludge handling structures and equipment Heating, ventilating, electrical and instrumentation systems Hydrogen Sulfide Corrosion Can Significantly Reduce the Useful Life of Sewers. ------- Figure 3. Approach to Identifying Existing and Potential Corrosion Problems REVIEW EXISTING INFORMATION TO IDENTIFY POTENTIAL; PROBLEM AREAS - Sewer maps - Locations of pipe replacement/rehab -, Odo/complaints - TV inspection logs CONDUCT PRELIMINARY INSPECTION AT POTENTIAL PROBLEM AREAS _ Visual inspection - Atmospheric K^S,, - Wastewater DO/sulfide - - ' 'pH of pipe crowns, channels, tank walls MEASURE CORROSION AT KNOWN ' PROBLEM AREAS , ' . A- ' - Manual measurement - Gore sampling - Sonic caliper inspection ESTIMATE CORROSION RATES AND PRIORITIZE AREAS FOR FURTHER MONITORING AND/OR CORRECTION ------- Hydrogen Sulfide Corrosion Can Cause Premature Failure of Electrical Systems Used in Pump Stations and Treatment Plants. Sewer maps should be gathered, updated and reviewed along with any. odor complaint logs, videotapes of sewers, maintenance-records and any other information sources that are available. Locations of potential corrosion problems, such as discharges of force mains, areas of odor complaints, pump stations, and plant headworks should be ' highlighted on a sewer map for further investigation. Figure 4 shows a typical sewer map with potential trouble spots targeted for inspection. Conducting Inspections A visual inspection should be conducted wherever possible. If entry into a manhole or confined space is required, precautionary measures as directed by OSHA and NIOSH should be carefully followed. A low-power scope used in conjunction with a mirror and a light source mounted at the end of a long rod can be used to inspect sewers without entry. Measuring pH of pipe crowns, and walls of man- holes, junction chambers and other confined spaces is probably the best early warning that a potential or existing corrosion problem exists. Color-sensitive pH paper can he used to determine the concrete surface pH. New pipe has a pH of about 10 but under corro,sive conditions, pH may be 2 or lower. Generally, pH values below 4 are indicative of corrosion problems. Atmospheric H^S is also a useful indicator of potential corrosion probleins. Dissolved sulfide concentrations in the wastewater should also be measured. The conditions of the sewer or structure, as well as other data collected, should be entered on an inspection checklist. Measuring and Predicting Corrosion Several techniques are available to measure the extent of corrosion. A simple but often inaccurate method is to remove the corrosioji product down to sound concrete and measure the depth of penetration. Extendable rods are also used to measure the inside diameter of the sewer. Coring of pipe crowns at cor- roded and uncorroded reaches provides good documentation of corrosion severity, and can be used to estimate depth of corrosion penetration and the thickness of remaining concrete over reinforcing steel. ------- Figure 4. Sewer Map Showing Locations of Potential Corrosion Problems PS i "- "Potential '"' Problem Areas A remote method of measuring corrosion is the sonic caliper. Sonic caliper technology is a relatively new development whereby sonic signals determine the distance from the transmitter to the target (e:g. crown, waterline, invert). Television inspection cannot be used to measure corrosion, but it can provide a relative indicator of the severity of corrosion to-the trained, observer. Predictive models exist to allow estimates of the rate of hydrogen sulfide generation and corrosion, and the anticipated service life of a sewer or structure. These empirical equations are presented in publications by, the U.S. Environmental Protection Agency, the American Society of Civil Engineers and the Amer- ican Concrete Pipe Association. As with all predictive models, actual data should be collected to confirm and calibrate the predictive equations. Prioritizing Problem Areas Rates of corrosion can be estimated based on physical measurements br predictive models. Where data are available on depth of corrosion penetration, average corrosion rate can be calculated by dividing corrosion depth by the age of the pipe or structure. The remaining useful lifetime of the pipe can then be estimated based on, for example, corrosion reaching reinforcing steel. This information serves as a basis for prioritizing areas for corrective action. For example, if severe damage has already occurred, replacement or rehabilitation may be necessary. If damage is not extensive but the service life has been significantly reduced, implementation of a corrosion control program may be warranted. ------- Chapter 5 How Do I Control Corrosion? There are- several methods available to control the rate of hydrogen sulfide. corrosion. These include 1) reducing the dissolved sulfide content of the wastewater, 2) using corrosion-resistant materials and coatings, 3) providing ventilation of the enclosed area or sewer, and 4) conducting routine preventative maintenance. These techniques are discussed below and presented in Table I.- Dissolved Sulfide Reduction 1. Oxidation by addition of chemical oxidants such as hydrogen peroxide, 'chlorine or potassium permanganate, or by the introduction of air or, oxygen. 2.' Precipitation of dissolved sulfide by the addition of metallic salts such as ferrous chloride and ferrous sulfate. Atmospheric hydrogen sulfide levels can be reduced by controlling the amount of dissolved sulfide available in the wastewater. Three basic techniques are used to achieve this goal. 3. pH elevation through the addition of , sodium hydroxide (caustic soda). Table 1, Sumniaty of Corrosion Control Methods CLASSIFICATION, 1. Dissolved sulfide redaction Oxidation .. , Precipitatiott' pS Elevation 2, Corrosion-resistant " materials and coatings 3. Ventilation 4, Maintenance METHOD ygen, air, hydrogen peroxide, Chemical or biochemical oxidation of, Chlorine or potassium permanganate ^sulfide .. ", , , -'"'". /J>, addition , ' ' - , , , '"',-' ,: --"''" "'; ,;-' * ^ ; 4. v. ""-. ^ ' f v ,Iron salt addition 'H " , , , Chemically binds sulfide ta form -' " '^'-insoluble precipitate Slug doses of sodium hydroxide Inactivates sulfate-reducing bacteria Use <>f corrosion resistant metals. Material is resistant to acid attack; plastics, concrete* application of and/or provides Effective barrier corrosion resistant paints or coatings against H^S or iacid migration ^ Mechanical ^ventilation of enclosed Redwces atmospheric H^S levels and spaces; purging with clean air or surface moisture , nitrogen '! '?,, ',*" ~ ' -' , , -,- Sewer cleaning by flushing or Minimizes accumulation of debris that pigging / " 'c^h. refute velocities, increase organic- > '-'. * matter deposition and increase sulfide " , - ' * " , ,''".. generafiou ^ , ' , ^ ^/ ^ " " . f. ff \ f St ff f -f ' " '' V v ~- * \ v"1 *' * f s * "" ' ** ------- The basic goals and treatment levels for the three basic techniques must be developed individually for each system, but generally the goals strive to meet the following guidelines: 1. Maintain dissolved oxygen greater than . ' 0.5 mg/1. " 1. Keep dissolved, sulfide levels below 0.3 mg/1. \ 3. Maintain atmospheric hydrogen sulfide levels below 5 pp'm. 4. Increase concrete pH to 4 or greater. Corrosion-Resistant Materials and Coatings Another method used to prevent corrosion or control the rate of corrosion is'to utilize corrosion-resistant materials, both in the collection system and at the wastewater treatment plant. Corrosion-resistant - materials fall under the following categories: 1) metallic coatings, 2) metal alloys, 3) corrosion- resistant concrete, and 4) plastics. Metallic coatings include galvanizing and electro- plating systems. Metal alloys include copper, aluminum, nickel; and stainless steel. The corrosion resistance of concrete can be improved by two ways: 1) use of high alumina or high-silica cement, or, 2) use of calcareous (e,g. limestone) aggregate. The use of such concrete in low-pH environments may still lead to concrete degradation but at a somewhat lower rate. In cases where corrosive conditions are anticipated, concrete pipe can be manufactured with a cast-in-place PVC liner. The use of polyvinyl chloride, polyethylene, fiberglass reinforced polyesters and other plastics are becoming more commonplace in,the wastewater field. Many of these matefiajs offer excellent corrosion' resistance. Certain paints and protective coatings can provide some degree of corrosion resistance. Paints and protective coatings include vinyl, epoxy and silicone resin primers and paints. Paints can be classified as either thermoplastic, which is applied hot and cured by cooling, or thermosettihg, which cures by chemical reaction with a setting agent. Thermo- plastic paints include asphaltic/coal tar and polyethylene; thermosetting, paints include polyurethane and epoxy. The proper preparation, application and-curing procedures must be closely followed for any coating system to be successful. Even adherence to proper procedures may not result in adequate coating performance in corrosive environments,, as the success of such coatings has. been highly variable. Ventilation Ventilation of sewers and enclosed spaces can potentially'reduce hydrogen sulfide corrosion by reducing the concentration of hydrogen sulfide in the atmosphere, and by drying the walls of the pipe or structure. Ventilation of sewers apparently had some success for corrosion control in Austin, Texas, Los Angeles, California and Sydney, Australia. Air discharged from a sewer would normally require treatment to control odors. There is some question regarding the effectiveness and practicality of controlling corrosion by this technique. Ventilation with clean air can be used to control corrosion in electrical cabinets or rooms housing sensitive electronic equipment. Electrical cabinets can be purged with nitrogen to provide excellent corrosion protection. Maintenance Routine sewer cleaning can be an effective deterrent to the hydrogen sulfide corrosion process. This is because accumulations of debris tend to reduce the wastewater velocity and thus increase its detention time within the sewer, allowing it to be.come anaerobic. As the wastewater velocity decreases, further deposition of organic matter occurs, which results in increased biological activity, depletion of oxygen, and generation of,sulfide. Deposition of solids is likely due to excessively flat sewer grades combined with low flows - these areas should be ' monitored for solids accumulation. Gravity sewers should be routinely flushed or pressure-washed; force mains may require pigging. ------- Chapter 6 What Options Do I Have To Rehabilitate Corroded Sewers? Methods Available Various methods are available for rehabilitating corroded sewers, and these methods continue to be improved. The basic categories are as follows: Excayation and replacement Cured-in-place inversion lining Insertion renewal Liners . Specialty concrete Excavation and replacement is usually the most costly and most disruptive means by which to correct sewer deficiencies. The same problem will likely redevelop however, if a similar honcorrosion-resistant material is used in the replacement without other corrective measures taken to decrease the severity of the corrosion problem. ' - Trenchless.technology is presenting new methods to protect against corrosion. One such method is the use of cured-in-place inversion linings, whereby a flexible "sock" is inserted into the pipeline, set in place by the addition of water, and cured in place. Rehabilitation Using Cured-in-Place Inversion Lining Can Be An Economical Alternative To Replacement of Severely Corroded Sewers (photo courtesy of Insituform, Inc.) ------- Insertion renewal consists of jacking a pre-formed pipe through the.existing sewer. Some methods involve the use of an insertion pipe of slightly smaller diameter than the existing sewer, while others involve the use of a,tool which first breaks away the existing sewer and is followed immediately by the new pipe. Ah alternate method of insertion renewal involves the use,of a deformed pipe which is inserted and then expanded to its final shape. Insertion of a corrosion-resistant liner made of fiberglass, PVC, or polyethylene is an effective means of sewer rehabilitation (photo courtesy of Price Bros., Inc.). ------- Liners can be used on larger-diameter sewers. Prefabricated PE or PVC panels are installed onto the existing pipe substrate, forming a continuous inter- locking strip. , ' ' Specialty concrete consists of different cements and/or aggregates which are more resistant to hydrogen sulfide corrosion than Portland cement concrete. These concretes may still be susceptible to corrosion, though at a reduced rate. Table 2 summarizes the principal methods of pipeline rehabilitation. Table 2, Principal Methods fa* Pipeline Rehabilitation METHOD Insertion Renewal (Sliplining) Deformed Pipe Insertion Cured-in»PIaee Inversion Lining ._ \ J Specialty Concrete (Spot repair) Coatings , - Liners Pipe Replacement ?. ,Exterior Wrap and Cap APPLICATION Used for cracked or deteriorated sewer pipes* '" Similar applications as for sliplinirig but for ' ^ "', ..relatively small (<24) circular pipe* Sewer pipe of any geometry^ largest current application is for 96 inch diaineter pipe, Large sewers or manholes needing structural , repairs. " , ' - ' Rapidly growingjaiethod for pipes and man- holes with new application methods being marketed continually; variable effecftvness. ;__ f i Should Be used oiily iiistructurafly sound sewers. Can easily fit variations in grades* slopes; cross-section for manually applied strip applications. ~ . .. t s " ' Any pipe with major structural defects,. Provides back-up corrosion protection and structurally reinforces existing pipeline. Simi- . . - , lar method applicable to monolithic structures. Selecting a Rehabilitation Technique The rehabilitation method to be used in pipeline repair is dependent upon the actual cpndition of the existing,sewer, its location, number of service connections, surface cover and intended service life. These factors also directly impact the cost to perform the'work. " . In cases where the wastewater flow within the existing pipe cannot be diverted, sliplining may be the only practical approach short of constructing a new sewer. In most situations however, both tangible and intangible factors will enter into the decision- making process. ------- Chapter 7 Conclusions Hydrogen* sulfide corrosion is .suspected to occur in over 50% of all wastewater collection and treatment facilities, regardless of geographic location, age or size. In some cases, the first sign of hydrogen sulfide, corrosion problems is a sewer collapse or other catastrophic failure. On a national scale, the cost to correct existing corrosion problems is estimated to be in the billions of dollars. Many communities will need to spend millions of dollars in the near future to address the consequences of hydrogen sulfide corrosion. Establishing a corrosion monitoring plan and conducting corrosion inspections as part of routine operation and maintenance will provide valuable information on the conditions of existing systems, shed insight into the causes of hydrogen sulfide corrosion problems, and allow selection of cost-effective approaches to control corrosion. The end result will be collection systems and treatment facilities that last longer and operate more efficiently. The cost of monitoring and control of corrosion will be easily offset by the savings accrued by avoiding premature replacement or rehabilitation. ------- Chapter 8 Sources of Additional Information Several recent publications are available from EPA that address the problems of hydrogen sulfide corrosion, procedures for detecting and controlling corrosion, and methods for rehabilitating corroded sewers and structures. These include 1) Hydrogen Sulfide Corrosion in Wastewater Collection and Treatment Systems, Report to Congress; ' 2) Detection, Control, and Correction of Hydrogen Sulfide Corrosion in Existing Wastewater Systems; and 3) Handbook - Sewer System Infrastructure Analysis and Rehabilitation. These and other relevant publications are listed in Appendix A. Questions regarding, the EPA publications listed above may be directred to the EPA Office of Wastewater Enforcement and Compliance,- Municipal Technology Branch at (202) 260-7356, or to one of the EPA Regional Offices shown in Appendix B. ------- ! APPEND IX A References Morton, R., R. Caballero, Ching-Lin Chen 7. and J. Redner, Study of Sulfide Generation and Concrete Corrosion of Sanitary Sewers. In-house report; Sanitation Districts of Los Angeles County, Whittier, CA, 1989. ' '-- -/ National Sewer Rehab Projected at $6 Billion, Civil Engineering, pp. 20-24, July, 8.. 1991. A Guide to Safety in Confined Spaces, National Institute for Occupational Safety and Health (NIOSH), No. 87-113,. Morgantown, WV. Bowker, R.P.G., J.M. Smith, and N.A. Webster, Odor and Corrosion Control in Sanitary Sewerage Systems and Treatment Plants, Design Manual, U.S. Environmental 10. Agency, Center for Environmental Research, Cincinnati, OH, 1985. . Sulfide in Wastewater Collection and Treatment Systems, ASCE Manual No. 69, American Society of Civil Engineers, New 11. York, NY, 1989. Sulfide and Corrosion Prediction and Control, American Concrete Pipe Association, Vienna, VA, 1984 Redner, J.A., R.P. Hsi, and E.J. Esfandi, Progress Report - Evaluation of Protective Coatings for Concrete, paper presented at EPA Technology Transfer Seminar on Sewer System Infrastructure Analysis and Rehabilitation, 1991. Sulfide Corrosion in Wastewater Collection and Treatment Systems, Report to Congress, U.S. Environmental Protection Agency, Office of Water,' Washington, DC, 1991. Hydrogen Sulfide Corrosion in Wastewater Collection and Treatment Systems, Report to Congress - Technical Report, U.S. Environmental Protection Agency, Office of Water, Washington, DC, 1991. /*' f Detection, Control and Correction of Hydrogen Sulfide Corrosion in Existing Wastewater Systems, U.S. Environmental Protection Agency, Office of Water, , Washington, DC, 1991. Handbook -Sewer System Infrastructure Analysis and Rehabilitation, EPA-625/6- 91/030, U.S. Environmental Protection Agency, Center for Environmental Research Information, Cincinnati, OH, 1991. ------- APPENDIX B EPA Regional Offices U.S. EPA Region 1 John F. Kennedy Federal Building Room 2203 Boston, MA 02203 (617) 565:3715 U.S. EPA Region 2 26 Federal Plaza Room 900 New York, NY 10278 (212) 264-2657 U.S. EPA Region 3 841 Chestnut Street Philadelphia, PA 19107 (215) 597-9800 U.S. EPA Region 4 345 Courtland Street NE Atlanta, GA 30365 (404)347-4727 U.S. EPA Region 5 230 South Dearborn Street Chicago, IL 60604 (312)353-2000 , Connecticut Maine Massachusetts New Hampshire' Rhode Island Vermont New Jersey New York Puerto Rico Virgin Island Delaware District of Columbia Maryland Pennsylvania West Virginia Virginia Alabama Florida j Georgia Kentucky Mississippi North Carolina South Carolina Tennessee Illinois Indiana Michigan Minnesota , \ Ohio Wisconsin U.S. EPA Region 6 Arkansas 1201 Elm. Street Louisiana Dallas, TX 75270 New Mexico (214) 655-6444 Oklahoma Texas U.S. EPA Region 7 Iowa 726 Minnesota Avenue ' Kansas Kansas City, KS 77101 Missouri (913) 236-2800 , Nebraska U.S. EPA Region 8 ' Colorado One Denver Place - Suite 1300 Montana 999 l'8th Street . North Dakota Denver, CO 80202-2413 South Dakota (303) 293-1603 ** Utah 1 Wyoming U.S. EPA Region 9 : Arizona 75 Hawthorne Street v California San Francisco, CA 94105 Hawaii (415) 744-1305 , Nevada U.S. EPA Region 10 Alaska 1200 Sixth Avenue Idaho Seattle, Washington 98101 Washington (206)442-5810 . ~ Oregon NOTE: The telephone numbers listed are general information numbers only; please ask for the program office to obtain specific information on the issues discussed in this booklet. ------- |