United States
Environmental Protection
Agency
Office of Water
(WH-595)
September 1991
832S91100
&EPA
Hydrogen Suitide Corrosion:
Its Consequences,
Detection and Control
&*&;&-..
/*f .1
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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.)
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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.
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.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.
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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
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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
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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.
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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
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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.
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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.
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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 * "" ' **
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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.
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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.)
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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.).
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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.
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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.
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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.
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! 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.
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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.
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