430990015
PROCEEDINGS OF
THE U.S. ENVIRONMENTAL PROTECTION AGENCY
MUNICIPAL WASTEWATER TREATMENT
TECHNOLOGY FORUM
1990
March 20-22, 1990
Orlando, Florida
''-'-:-, IL" Cf'-' "-. '"') ^"''"'!'3 Floor
September 1990
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ACKNOWLEDGEMENTS
This document was prepared by Eastern Research Group, Inc., Arlington, Massachusetts,
under EPA Contract 68-C8-0023. Carol Wendel was the Project Manager. Technical direction
was provided by Atal Eralp and Wendy Bell of the EPA Office of Municipal Pollution Control.
Additional support in compiling the appendices was provided by Charles Vanderlyn. The text
was based on attendance at the Forum, transcriptions of the presentations, and submissions
made by the speakers. It was reviewed by all the Forum speakers. Their time and
contributions are gratefully acknowledged.
NOTICE
Mention of trade names or commercial products does not constitute endorsement or
recommendation for use by EPA
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PREFACE
The 1990 Municipal Wastewater Technology Forum, sponsored by EPA's Office of
Municipal Pollution Control (OMPC), provided the opportunity for wastewater treatment
professionals from the Federal and State governments as well as Canada to discuss foremost
wastewater treatment technology development and transfer issues. Presentations were made on
sludge management, secondary treatment technologies, operations and maintenance (O&M)
issues for publicly owned treatment works (POTWs), constructed wetlands, disinfection, toxicity
management, and small community wastewater technologies. Three well-attended field trips
allowed participants to visit treatment plants that employ some of the discussed technologies.
The Forum represents a part of OMPC's National Technology Support Program. One
of the main elements of this program is the Wastewater Technology Transfer Network
(WTTN), which supports and enhances the network of Regional and State wastewater
technology transfer coordinators. This yearly meeting provides these coordinators with the
opportunity to exchange information and learn from each other about promising and problem
technologies.
The impending new sludge regulations and the close-out of the construction grants
program are just two of the changes taking place at the Federal level. These changes present
new challenges to all those involved in wastewater technology development and transfer. The
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widespread geographical representation (9 Regions and 35 States) at this year's meeting has
been very helpful to OMPC in its efforts to establish the WTTN and provide useful assistance
to States and municipalities.
In addition to providing summaries of the speakers' presentations, this document
contains several appendices that can be useful to those involved in the WTTN:
Appendix A includes the Forum Agenda and a list of the speakers' addresses that
can be used to obtain more information about the presentations.
Appendix B is a list of national contacts for wastewater technology, sludge
technology, and O&M operator training.
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Appendix C is a list of addresses for Regional and State wastewater technology,
sludge, and O&M coordinators.
Appendix D lists EPA's Regional wastewater treatment outreach coordinators.
Appendix E is a summary of the innovative and alternative (I/A) technology
projects by State.
Appendix F lists the current status of EPA's modification/replacement (M/R)
grant candidates by State.
Appendix G is a list of wastewater technology publications.
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TABLE OF CONTENTS
Page
INTRODUCTION
Keynote Address 1
State of Florida Welcome 6
SLUDGE MANAGEMENT TECHNOLOGIES
Trends in Municipal Sludge Management Practices 11
Organic Contaminants and Land Application of Municipal 16
Sludge in Canada
Alkaline Pasteurization of Municipal Sludges for 24
Beneficial Utilization
Odor Control for Composting 31
SECONDARY TREATMENT TECHNOLOGIES
Autoheated Thermophilic Aerobic Digestion 39
Captor Study of Moundsville/Glendale 44
Municipal Wastewater Treatment Works
Physical-Chemical Process Provides Cost-Effective 51
"* Secondary Wastewater Treatment
Biolac Technology Evaluation 56
O&M Issues for POTWs 64
Denitrification Using Submerged Rotating Biological 68
Contactors: A Case Study
Overview of the National CSO Strategy 78
Combined Sewer Overflow (CSO) Management 81
in EPA Region I
Combined Sewer Overflow Plan for East Lansing 89
Michigan
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TABLE OF CONTENTS (cont)
Page
CONSTRUCTED WETLANDS FOR WASTEWATER MANAGEMENT
Overview of Wetlands Treatment in the United States 93
Design of Constructed Wetlands/ Status of 98
Constructed Wetlands in Missouri
Operational Performance of Reedy Creek Wetlands 103
Treatment System and Other Southern Wetlands
Constructed Wetlands at Iron Bridge Treatment Plant: 109
Orlando Easterly Wetlands Reclamation Project
Compliance with Permits for Natural Systems 113
Inventory of Constructed Wetlands Systems in the United 115
States and WPCF Manual of Practice on Natural Systems
DISINFECTION
Ultraviolet Disinfection Studies at Rehobeth Beach, 119
Delaware
EPA Region V Special Evaluation Project of 129
Chlorination-Dechlorination
SMALL FLOWS CLEARINGHOUSE
National Small Flows Clearinghouse Computer Bulletin Board 133
TOXICITY MANAGEMENT AT POTWS
Technologies for Toxicity Removal at POTWs 137
Development of Computer-Based Model and Data Base 147
for Predicting the Fate of Hazardous Waste at POTWs
Plant Performance Evaluation: Cross Creek Wastewater 156
Treatment Plant, Fayetteville, North Carolina
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TABLE OF CONTENTS (cent)
Page
WASTEWATER TECHNOLOGIES FOR SMALL COMMUNITIES
EPA's Small Community Strategy 165
Appropriate Technologies for Small Communities 167
New Developments for Small Community Sewer Systems 169
Community Mound Systems 176
Sequencing Batch Reactors 180
Applications of Lagoons and Overland Flow Treatment 189
to Small Communities: Emmitsburg, Maryland -
A Case Study
Review of Lagoon Upgrades in Missouri 197
City of Sanford, Rorida, Water Reclamation Facility, 202
Reclaimed Water Spray Irrigation System, and
Vacuum Sewer Collection System
APPENDIX A
APPENDIX B
*\
APPENDIX C
APPENDIX D
APPENDIX E
APPENDIX F
APPENDIX G
AGENDA AND LIST OF SPEAKERS
LIST OF NATIONAL CONTACTS FOR WASTEWATER
TECHNOLOGY, SLUDGE TECHNOLOGY, AND OPERATIONS
AND MAINTENANCE OPERATOR TRAINING
LIST OF ADDRESSES FOR REGIONAL AND STATE
WASTEWATER TECHNOLOGY, SLUDGE, AND O&M
COORDINATORS
EPA REGIONAL WASTEWATER TREATMENT OUTREACH
COORDINATORS
SUMMARY OF INNOVATIVE AND ALTERNATIVE TECHNOLOGY
PROJECTS BY STATE
CURRENT STATUS OF M/R GRANT CANDIDATES BY STATE
LIST OF WASTEWATER TECHNOLOGY PUBLICATIONS
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LIST OF TABLES
Page
Table 1 Percent Recoveries of MC in Plant Uptake Studies 22
Table 2 Oxide Analysis of Cement Kiln Dust 25
Table 3 N-Viro Soil (PRFP) Beneficial Reuse Value Per Ton 30
Table 4 Average Operation Costs for the Regenerative Thermal 37
Oxidation System
Table 5 Proposed Criteria and Conditions for Hygienically 42
Safe Sludge in the Federal Republic of Germany
Table 6 Plant Effluent Results for the Moundsville/Glendale 47
Municipal Wastewater Treatment Plant
Table 7 Average Suspended Solids Loading Rates to the Primary 49
Clarifier of the Moundsville/Glendale Wastewater
Treatment Plant
Table 8 Summary of Existing Plant Waste Loads and Statistical 53
Analysis
Table 9 Pilot Test Effluent BOD, SBOD, and Effluent SS 54
Table 10 Summary Performance of Biolac Plants 62
Table 11 Iron Bridge WWTP Denite Pumpback Pilot Study 74
* Monthly Averages and Ranges
Table 12 Iron Bridge WPCF 1987 Operating Results 77
Table 13 Central Florida Wetlands Treatment Systems Summary 104
Table 14 Reedy Creek Natural Wetlands Treatment System No. 1 107
Performance Summary
Table 15 Reedy Creek Natural Wetlands Treatment System No. 2 108
Performance Summary
Table 16 Wetlands Nutrient Concentrations at Iron Bridge WWTP, Ill
1988 and 1989
Table 17 Wastewater Characteristics at Rehoboth Beach WWTP 124
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LIST OF TABLES (cont)
Page
Table 18 Bacterial Characteristics and Degree of Photorepair 125
at Rehoboth Beach
Table 19 Bacterial Inactivation Rates Estimated for Rehoboth Beach 126
Table 20 Comparison of Rehoboth Beach WWTP Fecal Coliform 127
Inactivation Rates with Other Plants
Table 21 Model Test: Comparing Predicted and Observed Removal 154
from Three Oil Refinery Wastewater Treatment Plants
Table 22 Model Test: Predicted Versus Observed Removal 155
from the Highland Creek WPCP
Table 23 Conventional Parameter Results: Influent, 160
Secondary Effluent, and Final Effluent
Table 24 Organic Compounds and Metals Results 161
Influent, Secondary Effluent, and Final Effluent
Table 25 Pure Oxygen System Operating Parameters 163
Table 26 Typical JetTech Operating Strategy 186
Table 27 Winter, Summer, and Ground-Water Parameters 193
for the Emmitsburg, Maryland, Wastewater Treatment Facility
Table 28 Actual Cost Projections for the Emmitsburg, Maryland, 195
Lagoon, Overland Flow, and Water Reuse Systems
Table 29 Lagoon System Upgrades in Missouri 198
Table 30 Expected Influent and Effluent Characteristics 209
for the Sanford Water Reclamation Facility
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LIST OF FIGURES
Page
Figure 1 Total and 22°C (Hatch-Marked) Recoveries of Four Volatile 17
Organic Contaminants from a Sludge-Treated Loamy Sand Soil
Figure 2 Total and 22°C (Hatch-Marked) Recoveries of Six Volatile 19
Organic Contaminants During a 24-Hour Period
Figure 3 Total and 22°C (Hatch-Marked) Recoveries of Six Volatile 20
Organic Contaminants During a 12-Day Period
Figure 4 Schematic of the Microcosm System Used to Study 21
Plant Uptake of Organic Contaminants
Figure 5 N-Viro PFRP Process Steps 27
Figure 6 Schematic of an Early Afterburner System 32
Figure 7 Schematics of Three Basic Afterburner Technologies 33
(1960s to 1980s)
Figure 8 Smith Regenerative Thermal Oxidation System 35
Figure 9 Flow Diagram of a Two-Stage ATAD Facility with 41
Heat Recovery
Figure 10 Schematic of a Compact Upflow Scrubber (Fuchs Biofilter) 43
Figure 11 Flow Diagram of the Tacoma, Washington, Pilot WWTP with 52
x Physical-Chemical Treatment
Figure 12 Biolac Aeration Chain Detail 58
Figure 13 Flow Diagram of a Typical Biolac-R System 59
Figure 14 Schematic of Integral Biolac-R System Clarifier 60
Figure 15 Original Iron Bridge Wastewater Treatment Plant 69
Process Flow Diagram
Figure 16 Iron Bridge Denite Pumpback Process Flow Diagram 71
Figure 17 Illustration of a Combined Sewer System 82
Figure 18 Typical CSO Near-Surface Storage System 87
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LIST OF FIGURES (cont)
Page
Figure 19 Typical CSO Storage Tunnel System 88
Figure 20 Schematic of the Rehoboth Beach, Delaware, Wastewater 120
Treatment Plant Operations
Figure 21 Schematic of the Rehoboth Beach, Delaware, WWTP with 122
the Ultraviolet Disinfection Equipment
Figure 22 Log On Procedures for the Wastewater Treatment 134
Information Exchange (Wilt)
Figure 23 Causative Agent Approach Flow Diagram 138
Figure 24 Source Testing and Treatment Flow Diagram 141
Figure 25 Source Treatment Technologies for Toxicity Reduction 142
Figure 26 Contaminant Removal Trends in PACT Systems 144
Figure 27 Effect of Solids Retention Time (SRT) on Toxicity 145
Reduction for Nonyl Phenolics
Figure 28 Predicted Versus Observed Effluent Concentration 150
for 2,4,6- Trichlorophenol
Figure 29 Predicted Versus Observed Effluent Concentration 151
for Cadmium
Figure 30 Predicted Versus Observed Stripping Removal Rates for 152
P-Xylene
Figure 31 Cross Creek, North Carolina, WWTP Flow Diagram 158
Figure 32 Typical Operation for a 2-Reactor CFID System 182
Figure 33 Typical Operation for a 2-Reactor IFID System 184
with Fill, React, Settle, Decant, and Idle Phases
Figure 34 Schematic of the Emmitsburg, Maryland, Wastewater 190
Treatment Plant Facility
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LIST OF FIGURES (cont)
Page
Figure 35 Schematic of the Emmitsburg, Maryland Overland Flow 191
System
Figure 36 Sanford, Florida, Vacuum Sewer Collection Valve Pit with 204
Above-Ground Breather
Figure 37 Sanford, Florida, Vacuum Sewer Collection System Gravity 205
Line Connection to Vacuum Valve Pit
Figure 38 Sanford, Florida, Vacuum Sewer Collection Station 206
Line Diagram
Figure 39 Flow Schematic of the Sanford, Florida, Water Reclamation 208
Facility
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INTRODUCTION
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KEYNOTE ADDRESS
Jack Lehman, Deputy Director, EPA Office of Municipal Pollution Control
Washington, D.C.
On behalf of Mike Quigley, Director of OMPC, and myself, welcome to the Municipal
Technology Forum, one of the more important activities OMPC conducts. Three main topics
may be of interest to the participants of this event, including current events, in Washington and
the rest of the world; the main themes of current EPA policy that affect the field of municipal
pollution control; and the municipal wastewater treatment programs conducted at OMPC.
Current events. In terms of current events, the 20th anniversary of Earth Day will take place
on April 22. Because the original Earth Day led directly to the formation of EPA in
December 1970, EPA also will celebrate it's 20th anniversary this year. As indicated by public
opinion, there is a lot of support for EPA activities as well as for Earth Day. Hopefully, this
enthusiasm will stimulate a renewal of the environmental ethic that we have in the United
States. For the celebration, EPA and other environmental groups will sponsor an open house
on the Ellipse behind the White House in Washington, D.C. Earth Day should be meaningful
and fun for us all, especially those of us in the environmental business.
** Another current event is the President's recommendation to elevate the Environmental
Protection Agency to a department level (making the Administrator of EPA a Cabinet
Secretary). Both Houses of Congress have similar bills pending to make this change. There is
a lot of momentum behind this initiative, so this change will likely take place some time this
year.
In Eastern Europe, there is a breathtaking pace of change taking place. Even though
these changes are occurring far away, they affect the way the United States approaches
environmental protection worldwide.
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EPA's current themes. One of the main themes of EPA policy that affects the field of
municipal pollution control is risk reduction. For example, the radon indoor air pollution issue
has been getting EPA's management attention. Lifetime risks of cancer for maximum exposed
individuals were being calculated in the range of 10'2 to 10'3. EPA's target for risk reduction
typically has been 10"4 to 10"*, one in a million, not one in a hundred. EPA focused primarily
on human health effects, but the Agency is now beginning to understand that there are risks
associated with ecological damage, as well.
One of Administrator Riley's main themes is good science. In some ways, everyone
wants to find the technology that will make some quantum leap forward in terms of pollution
control or risk reduction. "Silver bullets" are rare, but that doesn't mean that researchers
shouldn't try to find them. Additionally, wastewater professionals should keep improving the
present level of technology to make it as efficient and as low cost as possible.
Another current EPA theme is pollution prevention, defined by EPA as reducing or
eliminating pollution at its source before it is emitted, as opposed to controlling pollution after
it is produced. A growing number of EPA staff also include resource conservation, recycling,
reuse, and some aspects of sludge and wastewater reuse in the definition.
A fourth theme EPA is committed to is Total Quality Management (TQM), which is a
concept that emphasizes the quality of the product or service being offered and focuses on
"value-added" activities, team building, responsibility, and decision making. If done right, TQM
can be re-energizing and provide a new perspective on the work at hand.
Municipal Wastewater Treatment Technology Program. The focus of the Municipal
Wastewater Technology Program is to ensure that wastewater treatment facilities are in
compliance with the Clean Water Act. The two basic activities conducted by OMPC are
providing incentives to municipal facilities for compliance [such as construction grants or State
Revolving Fund (SRF) loans], and providing information on new technologies (technology
transfer), which can help municipal decision-makers achieve and maintain compliance. To
achieve these goals, OMPC seeks technological innovations through research and development
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to provide better, more cost-effective wastewater treatment. The Office provides technical
assistance to help solve problems, and operations and maintenance (O&M) assistance and
education training for operators and municipal decision-makers.
Technology support program. The technology support program promotes the acceptance of
effective treatment technologies presently in operation. The program involves managing,
supporting, and enhancing existing technology transfer networks and providing targeted direct
technical assistance in areas of national significance. The sources of information include OMPC
and ORD, which continue to produce technical studies that are shared with the Regional
offices, States, and municipalities. The Regions and States themselves generate technical studies
that are used by others and supported by OMPC, such as the revision of the Water Pollution
Control Federation (WPCF) Manuals of Practice.
OMPC also is setting up a Wastewater Technology Transfer Network, which is broader
in scope than the network it replaces, the Innovative/Alternative (I/A) Coordinators Network.
Network coordinators will monitor new technologies, identify new and emerging problems in
specific technologies, and respond to inquiries about these technologies. Other anticipated
activities include peer matching for problem solving; distributing technical information; and
cooperating with other networks already providing assistance to municipalities, such as the U.S.
Department of Agriculture Extension Service, the National Small Flows Clearinghouse, and the
Farmers Home Administration.
*\
Another aspect of this technology support program is to provide Targeted Direct
Technical Assistance to Regions and States, through telephone consultations, written
information, or referrals to qualified experts. As resources permit, in some instances, OMPC
will conduct site visits, based on whether the site is dealing with a priority issue, such as toxics
or the new sludge requirements. The problem also must be national in scope, not yet solved
satisfactorily, and have a significant environmental dimension.
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Existing support programs. EPA provides strong technical support through many other
programs, including SCORE, the Small Community Outreach and Education Program; the
MWPP, the Municipal Water Pollution Prevention Program; and the O&M Program.
SCORE was initiated about 4 years ago to address the municipal wastewater treatment
needs of communities of less than 10,000 people. The program awards Incentive Grants by the
Regions to establish State outreach programs, and includes financial management planning
grants, public education, and operation and maintenance activities. SCORE also promotes
Federal outreach coordination and Regional outreach activities by promoting innovative
approaches and helping communities set priorities.
SCORE works in cooperation with other existing networks (such as those mentioned
above) and EPA's Office of Drinking Water, because often in small communities, the
wastewater and drinking water facilities are operated by the same local office. SCORE also
deals with the International City Managers Association, the National Association of Towns and
Townships, and so forth. SCORE administers the Small Flows Clearinghouse and computer
bulletin board at the University of West Virginia (see p. 133); is developing a national policy on
municipal water use efficiency; and produces brochures on financial management and planning.
The Municipal Water Pollution Prevention Program encourages "preventive medicine"
*x
through self-auditing by POTWs once per year, which has proven to be successful in terms of
compliance rates. The program also can improve planning for capacity increases and financial
needs. The MWPP involves a substantial amount of technical assistance because some of the
solutions require innovative technologies.
The O&M program (see p. 64) includes running an onsite assistance program, as
mandated by Section 104 (g) of the CWA; operating 39 Environmental Training Centers, as per
Section 109 (b); and sponsoring annual operator training conferences and a very successful
awards program, presented in conjunction with the Water Pollution Control Federation
(WPCF). O&M program personnel also visit small treatment plants that are having trouble to
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study the performance-limiting factors and provide feedback to system designers. The program
publishes a quarterly newsletter called On-sitelOversight.
Summary. OMPC's mission in the National Technical Support Program and the other
programs discussed above is to distribute technical information, promote networking among
members and other groups, and provide technical assistance to POTWs. These activities all
confirm OMPC's commitment to continue Technology Assessment and Technology Transfer
initiatives.
The agenda for this conference is ambitious and exciting and will give the participants a
thorough update on EPA programs that cover international activities, O&M issues, combined
sewer overflows (CSO), and several small community programs. Speakers will present
information on the cutting edge of municipal wastewater treatment technology in the areas of
sludge management, secondary treatment, constructed wetlands, disinfection, toxicity, and small
community sewage systems. The conference also includes field trips to a phosphorus removal
facility, an in-vessel composing plant, a vacuum sewer system, and two constructed wetlands, and
several interagency workgroups on small wastewater systems.
This conference is a major commitment of time for all participants. OMPC aims to
make this an energetic event, provide some "quality value-added time," and make sure all
participants take home new knowlege to apply towards solving the major issues facing the field
of municipal wastewater treatment. This conference also intends to help participants realize
how their work coordinates with EPA policies and the worldwide situation. Only with proper
wastewater treatment technology can the entire municipal pollution control program succeed.
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STATE OF FLORIDA WELCOME
Robert E. Heilman, Chief
Bureau of Water Facilities Planning and Regulation
Florida Department of Environmental Regulation
Good morning. On behalf of the Department of Environmental Regulation (DER), I'd
like to welcome you to the great State of Florida and to the beautiful City of Orlando.
I'd like to briefly share some interesting statistics with you to give you an appreciation
of the environmental situation we have here in Florida. Florida's population is growing at the
rate of 6,000 persons each week. Almost 80 percent of the 12 million people in Florida live
near the coast The rest of the population either lives on or near inland surface waters.
Near the coast, ground-water supplies are limited, shallow, and vulnerable to salt water
intrusion. Furthermore, Florida does not have large, rapidly flowing streams that can assimilate
large volumes of wastewater discharge. Florida's numerous streams tend to be small, flow
slowly, are warm year round, and flow into lakes or coastal waters that are prone to excessive
growth of algae and nuisance aquatic weeds.
In a State that depends upon high quality surface water for an important tourist
industry, as a drawing card for growth and development, and as a basis for a high quality life,
protection of our water resources is a formidable task.
In a recent statewide public opinion survey, conducted by the Florida State University
Survey Research Laboratory for the Department of Environmental Regulation, water pollution
was identified as the chief environmental concern. The survey also indicated that our State
government is doing as well as, or better than, other States in environmental protection.
So, now that we've gotten these high marks from the regulated public, what have we
done to protect Florida's fragile environment? To that end, Florida has been on the cutting
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edge of environmental protection in a number of ways. First, more and more surface water
discharges are required to meet advanced wastewater treatment requirements. We are moving
farther and farther away from secondary treatment being a minimum requirement. In Florida,
advanced waste treatment is now becoming the "norm11 in most of our permits.
Secondly, due to the ever increasing demand on our potable water resources from the
growing population and the limited assimilative capacity of receiving waters, there is an
increased emphasis on reusing our treated wastewater for a multitude of purposes. We now
look at our wastewater treatment facilities as "water factories." Rather than treatment and
discharge, the reclaimed water from these facilities is used for landscape irrigation, agricultural
irrigation, ground-water recharge, industrial use, fire protection, toilet flushing, aesthetic
fountains and ponds, construction dust control, and wetland restoration. This not only reduces
the potable demand, but reduces the load on the receiving streams. In Florida we have some
nationally acclaimed reuse projects such as:
SL Petersburg Dual Distribution System, where over 6,000 residential laws
receive reclaimed water for irrigation.
Conserv n, which is an award-winning project using reclaimed water from
Orange County and Orlando for irrigating 7,000 acres of citrus groves and 10
acres of ferns.
Tallahassee Spray Irrigation System, where the city of Tallahassee irrigates
> approximately 2,000 acres of com, soybean, and other fodder crops with
reclaimed water.
Orlando Wetlands, which uses reclaimed water to feed a 1,000 acre wetland
system used for hiking, jogging, and nature observation.
Other reuse systems are located in Cocoa Beach, Naples, Altamonte Springs, and
Palm Beach County.
By 1991, mandatory reuse programs will be required in critical water supply problem areas
throughout the State.
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Another area where Florida is encouraging beneficial reuse is in the area of land
application of sewage sludge, or as we now call it here, "domestic wastewater residuals." We
have just completed a year's work in developing a new domestic wastewater residuals rule to
control the disposal practices and document the quality and quantity of these residuals that are
land applied. There are approximately 220,000 dry tons of residuals generated in the State of
Florida annually. Approximately 70 percent of these residuals are land applied. The previous
rule did not provide any accountability for the residuals produced by the wastewater treatment
facilities. For the most part, once the disposer picked up these residuals from the treatment
facility, no one but the disposer knew where they were going. Our new rule corrects this
deficiency without discouraging the current disposal practices. We have developed a rule that
requires the generator to be liable for the disposal of the residuals unless he has transferred
that liability through a legally binding agreement. The rule also requires agricultural use plans
or dedicated site plans for the application sites. We feel this new rule will produce the level of
accountability that we must have to protect the public.
The last area I'd like to discuss is toxicity and how Florida is dealing with it. The State
of Florida is not an NPDES-delegated State. Therefore, EPA issues federal permits for surface
water discharges and we issue our own State permits. As we are all discovering, we can no
longer just look at conventional pollutants for discharge permits, but we must also consider the
nonconventional constituents. We are finding more and more facilities are adversely impacting
the receiving streams they discharge to through heavy metal toxicity, ammonia toxicity, and even
*\
chlorine toxicity. Our existing rules regarding toxicity differ somewhat from EPA's. In our
rules, we do not recognize the zone of initial dilution. While many EPA permits require 48-
hour acute toxicity tests and the DER often uses 48-hour tests for screening purposes, our
permits require that 96-hour tests be conducted to show compliance with DER acute toxicity
regulations. A final area where we differ with EPA is in the species selected for testing
toxicity. Some of the State's requirements are more restrictive than EPA's, but we feel they
are necessary to protect our surface waters. During the next 5 years, we anticipate that toxicity
testing and biomonitoring requirements will be incorporated into the permits of all major
domestic and industrial facilities discharging to surface waters.
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In closing, the State of Florida needs and appreciates these kinds of technology forums.
It is essential that research efforts in the wastewater treatment field continue in order for us
and other States to meet future water quality goals. The future demands for environmental
protection that will be made of State agencies can only be met if technological advances in
wastewater treatment are continued. Without technological solutions to environmental
problems, rules and regulations are meaningless.
As we approach the 20th anniversary of Earth Day on April 22 and also the 20th
anniversary of the Clean Air Act in October 1992, I believe a new era of environmental
awareness is taking place. The public's awareness of environmental problems is at the highest
level ever. For the Department of Environmental Regulation, every day is "Earth Day." We
have come a long way in 20 years, but still have a long way to go. To get there, we need
people like you. Thanks for being here and I hope you all enjoy your stay in our great State.
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SLUDGE MANAGEMENT TECHNOLOGIES
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TRENDS IN MUNICIPAL SLUDGE MANAGEMENT PRACTICES
Timothy G. Shea
Engineering Science, Inc.
Fairfax, Virginia
Introduction. It is encouraging that this technical program for 1990 is initiated with an
overview of the directions being taken in municipal sludge management practices. The
proportionate amounts of time, dollar, and other resources devoted to sludge management
continues to increase in municipal treatment plant budgets each year, driven by each new
environmental initiative from the Congress. Within the next few years, we will see the
implementation of the ocean sludge dumping ban in the New York-New Jersey Metropolitan
Area, full secondary treatment in Southern California and in the Metropolitan Boston area, and
air toxics emissions controls on wastewater treatment plants in many urban centers of the
nation. At the same time, we will see the implementation of the Part 503 sludge management
regulations in a form not likely to be much different from what was promulgated in February
1989 and the continued emphasis on the reduction of effluent toxicity.
The sludge quality and production at a POTW is typically impacted adversely by any
environmental initiative. The continuing flow of environmental initiatives expected in the 1990s
will therefore keep the pressure on municipal sludge managers, and sludge management costs
witi continue to rise accordingly. That cost will become an increasing fraction of the wastewater
treatment budget and ultimately motivate the larger cities toward mega-solutions. Typical mega-
solutions will include long distance rail haul to remote landfills or land reclamation sites, and
electrical power production facilities using local sludge production as a small component of the
fuel supply for regional electrical and steam power production centers. How far ahead are
these developments? My conjecture is: "within the decade." To see how I arrive at this
conclusion, let me share with you a brief look at where sludge management is today and where
it is going.
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Where are we starting the nineties? As this decade begins, we continue to see municipal
wastewater treatment plant projects take 7 to 10 years to implement from start to finish.
Secondary treatment is in place around the nation, but we now appear to be headed to minimal
levels well beyond this in environmentally sensitive areas. With reference to sludge processing,
anaerobic digestion has become a mainstay in most of the major plants in the nation, but as
higher treatment levels become more common, the continuation of this practice will be
questioned as nutrient removal is implemented, making the treatment of supernatant more
costly. Lastly, as was noted above, the decade is starting with numerous regulations in the
development process, and it should be obvious to all that there will be significant changes in
accepted treatment practices ahead.
Example impacts of the new regulations. To build on this theme, let us for a moment consider
some of the impacts of the new regulations. The pathogen reduction requirements of the new
Part 503 regulations will require the installation of new or alternative terminal sludge processes
at many plants. The health risk basis of these same regulations will require extensive upgrades
of the APC (air pollution control) systems at most of the multiple hearth furnace installations
in the nation. The BACT (best available control technology) air quality mandates of many
States will add stringent APC requirements for sludge dewatering, composting, and lime
stabilization processes. Toxicity reduction rules will result in the concentration of these
materials with new sidestream treatment processes being needed to minimize adverse quality
impacts on sludge quality.
x
At the same time, the implementation of the CSO and stormwater rules this year will
result in more in-line flow controls, and more flow into the main plant. These weaker flows
will have more inerts and street washoff and result in sludges with more metals and TPH (total
petroleum hydrocarbons). Meanwhile, new regulations in several States require that sludges
contain as much as 50 percent dry solids for landfill disposal.
It is in this same milieu that the cessation of ocean dumping of sludge is taking place.
This action alone will place some 200,000 dry tons annually of dewatered sludge from the New
York-New Jersey metropolitan area "on the street" in the early 1990s. The ancillary effects of
-12-
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this mandate have been seen already in the lack of excess centrifuge manufacturing capacity for
the next 2 or 3 years, as the vendors rush to fill orders for the ocean dumpers. Other effects
have included the issuance of an Executive Order by the Governor of Pennsylvania limiting the
influx of sludge and refuse to the State, and the rapid escalation in the cost of landfill disposal
for local jurisdictions in Pennsylvania, Ohio, and elsewhere.
Other trends are also taking place at the start of the 1990s. One of the most important
is the recognition, sometimes grudgingly, of the larger POTWs, that diversification of sludge is
essential to avoid the "Philadelphia syndrome" of not being able to move its compost
production. The Philadelphia situation is one of regional saturation of the markets, a
phenomenon ill-understood by the various participants in the sludge management industry.
Offsetting this is the development of new and innovative outlets for sludge products, including
the use of dried sludge pellets as chemical fertilizer bulking agents, and chemically stabilized
sludges as a substitute daily cover and base to final cover for landfills.
A look into the 1990s. A road map into the 1990s would show sludge going to incineration,
compost, substitute soils, and landfills at the start of the nineties, and, I conjecture, to
gasification by the end of the nineties. Let's start with dewatering to begin our look at the
trends. Dewatering to the 25 to 30 percent dry solids range will become commonplace as
agencies shift to better equipment that has been purchased after pilot testing and with
specifications tailored to the specific sludges at a plant. A movement towards high solids
*\
centrifuges will also continue in situations where compact space is available and where BACT
requirements must be met
In reference to substitute soils, there is a growing list of end uses with each new
installation. The breakthroughs with the chemical stabilization and fixation processes used to
produce substitute soils have been in the areas of pathogen destruction (requires enough
ammonia in the sludge), bearing capacity of the cured product, and the dilution of lesser quality
sludges with the "ingredients" added. One process flow diagram can serve many different
variations of the process (and there are many) with common equipment and curing facilities.
-13-
-------
Thus an installation that can produce a substitute soil has considerable flexibility, including as a
backup process.
The trend with composting has been toward continued process improvements to negate
early adverse experiences, which are replete in the literature. Also evident now are alternate
uses for compost, the development of "designer" products, and the introduction of more
sophisticated marketing techniques. On the negative side has been the regional saturation of
markets that seems to have occurred in connection with Philadelphia's products, and the 10 to
30 percent cost uplift that the installation of BACT air pollution control equipment can have
on the total project cost.
Incineration will continue to be a mainstay process for larger POTWs in the 1990s, but
with some important new developments. Improved energy recovery will be realized through
integrated steam and electricity production, and the use of steam for the drying of sludge prior
to incineration as well as for digester and space heating. APC efficiencies will be improved
through the incorporation of devices like the wet electrostatic precipitator and the regenerative
afterburner. Also plume suppression and less-than-GEP stack heights will become more
common as POTWs seek a "lower" and less visible profile. Lastly, ash management will become
more of a reality, with recovery and reuse a slow-to-develop but vital prospect.
^ As far as technology, I look to the integrated technologies that will use sludge and coal
as fuel to produce steam and electrical energy as the next major development to be
implemented by the end of the decade. Examples of such technologies are the variations of the
slagging gasification systems that Texaco and British Gas have developed. These processes use
sludge as a small (say 10 percent) fuel component with coal or oil as the mainstay. The feed
mixture is gasified in an environment that slags the ash while yielding a low BTU gas. The gas
is then used in a combined turbine to produce electricity, and waste heat is recovered as steam.
This technology is most suited to metropolitan areas where the electrical power utilities already
have the large sites, coal handling equipment, and power transforming, switching and
distribution equipment that are needed.
-14-
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The next 5 years. To conclude, a comment about the next 5 years is appropriate. I look to
sludge haul and disposal costs of $150 per wet ton from the New York-New Jersey
metropolitan area, with hauls being up to 200 miles by truck and 1,000 miles by rail. Around
the nation, there will be huge investments in new incinerators and in upgrades of existing units.
Ash recovery and reuse will become a fledgling industry, and the diversification of sludge
management programs will become commonplace. There will be substantial outlays for APC
equipment to control emissions of odors, criteria pollutants, and toxic pollutants, as sludge
managers anticipate and respond to the demands of the public. In summary, the agenda is full
and the expenditures required are great as we approach this new decade. Thank you for this
opportunity to offer my views.
For more information about these trends, contact Tim Shea (see Appendix A). See
Appendix E for a summary of EPA's innovative/alternative (I/A) technology projects.
-15-
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ORGANIC CONTAMINANTS AND LAND APPLICATION
OF MUNICIPAL SLUDGE IN CANADA
Melvin Webber, Wastewater Technology Centre, Environment Canada
Burlington, Ontario
Applying municipal sludge on agricultural land is a cost-effective method of sludge use
that recycles essential nutrients into the soil. It is practiced widely in Europe and the United
States and accounts for one-third of Canadian sludge production. Organic contaminants (OCs)
can enter sewerage systems through industrial and domestic effluents and remain in municipal
sludge. OCs in sludges that are applied to agricultural land have the potential to enter the
food chain and affect human and animal health. Sludge managers must, therefore, understand
the persistence of OCs, their fate in soils, and how to apply sludges that contain OCs on
agricultural lands.
Studies of volatile organics in soils. The Wastewater Technology Centre (WTC) of
Environment Canada conducted several laboratory studies to determine the persistence of
volatile organic contaminants (VOC) in soils containing varying amounts of organic matter and
clay. The first was a soil incubation study that measured the persistence of 1,1-dichloroethane
(DCE), trichloroethylene (TCE), toluene (TOL), and ethylbenzene (ETB) in sludge-treated
softs. The sludge was 3 percent dry weight (dw) in the soil. The concentration of each VOC
was 50 mg/kg, except TCE, which was 2.5 mg/kg. The tests were conducted at 22°C (room
temperature) and then heated to 95°C to determine total residual VOC levels in the soil. The
test systems were aerated at varying intervals. Gas chromatography and flame ionization
detectors were used to analyze samples.
The results of the studies are presented in Figure 1. Hatched sections of the bars
represent VOC volatilized at 22°C, and the open sections represent residual VOC in the soil
(i.e., the amounts volatilized at 95°C). At 22°C, the VOC recoveries increased continuously
from about 15 minutes to 2 days. There was almost no residual DCE and TCE in the soil
(95°C test) within 24 to 48 hours and almost no residual TOL and ETB in the soils within 144
-16-
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to 288 hours. The authors have no satisfactory explanation for the low recoveries of
chlorinated compounds (DCE and TCE), as indicated on Figure 1.
A second study considered a larger number of compounds and soil types. Figures 2 and
3 show the results of these tests for periods of 24 hours and 12 days. Patterns are similar for
the 24-hour and 12-day study periods. On average, the total amounts recovered after 24 hours
are closer to 100 percent than the total recoveries for the 12-day period. It appears that with
time, there is some degradation and/or irreversible sorption of compounds in the soils. These
effects are largest for muck soil with the highest organic matter.
Plant uptake studies. In another study, microcosms in which ryegrass was grown in sludge-
treated soils were used to study plant uptake of OCs. Figure 4 is a schematic of the
experimental system. "Carbon was used to label and then measure OCs in the system. Air was
drawn through the system continuously, to be able to recover 14C as either carbon dioxide or as
a volatile organic. Researchers also determined 14C levels in the plants after they were
harvested.
Some preliminary results of these studies are shown on Table 1. 14C recoveries in
ryegrass were small and indicated no appreciable uptake of the OCs. Recoveries of 14CO2
indicate considerable degradation of pentachlorophenol, and recoveries of "C-labeled volatile
organics indicate complete volatilization of 1,2,4-trichlorobenzene. Another study conducted
over a 19-week period showed a similar recovery pattern for anthracene.
Bioconcentration factors. The bioconcentration factor (BCF) is the concentration of 14C in the
plant material compared to the initial concentration of 14C added to the soil. A BCF of 1,
indicates that MC is not accumulating or being excluded from the plants. If the BCF is greater
than 1, there is some accumulation; if it is much less than 1, the material is not entering the
plants through the roots. In a study with 14C-labeled anthracene, the BCFs for ryegrass were
extremely low, suggesting that anthracene was not taken up by ryegrass.
-18-
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Organic Contaminants
-------
TABLE 1
PERCENT RECOVERIES OF MC IN PLANT UPTAKE STUDIES
COMPOUND
1 ,2,4-Trichlorobenzene
Anthracene
Benzo(a)pyrene
2,2',5,5'-Tetrachlorobiphenyl
Pentachlorophenol
CO2
3.7
8.2
1.0
1.2
67
Volatile
Organic
144a
0.01
0.02
0.02
0.08
Rye-
Grass
0.13
0.05
0.08
0.14
0.14
Total
147
8.3
1.1
1.4
67
"A high percentage was recovered for an unknown reason.
-22-
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Summary. This information indicates that VOCs escape relatively rapidly from mineral soils
and less so from soils with high concentrations of organic matter. It does not appear that
VOCs would cause a significant problem for agriculture. Additional information is needed
however, on persistence and plant uptake for other organic contaminants that may occur in
sludge.
The WTC plans to expand plant uptake and persistence studies in soils of representative
organic contaminants; study the fate of detergent builders, which according to European
information, can be present in sludge at concentrations greater than 1 percent by dry
weight; and conduct a survey of organic contaminants in Canadian sludges.
For more information, contact Melvin Webber (see Appendix A).
-23-
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ALKALINE PASTEURIZATION OF MUNICIPAL SLUDGES FOR BENEFICIAL
UTILIZATION
David S. Sloan, N-Viro Energy Systems
Coral Spring, Florida
The N-Viro "AASSAD" process is an advanced alkaline sludge stabilization process with
subsequent accelerated drying. The process stabilizes and pasteurizes wastewater sludges with
the use of alkaline materials and is EPA certified as a Process to Further Reduce Pathogens
(PFRP).
The objective of N-Viro Energy Systems (NES) is to create a product that requires
little control and that can be placed back in the community for beneficial use. Through its
Agency network, the company has projects on-line in Portland, Maine; Boston, Massachusetts;
Syracuse, New York; Bristol, Connecticut; Wilmington, Delaware; Toledo, Ohio; Lexington,
Kentucky; Des Moines, Iowa; Jupiter, Florida; and other locations. The product has been used
as an organic soil amendment, a liming material, as landfill cover, and other applications. N-
Viro soil has demonstrated community acceptability, numerous product markets, and low capital
and life-cycle costs. It also is a simple reliable operation that uses standard equipment.
*\
The alkaline admixture (AA), often a by-product kiln dust, has a pH that varies from 8
(if the dust is nonreactive and hasn't been calcified in the kiln) to slightly over 12, depending
on the amount of carbonate that has been driven off and calcium oxide that has been created.
The kiln dust contains a variety of oxides, primarily calcium in the form of calcium oxide (see
Table 2). It contains almost 6 percent potassium, which is what is missing from most sludge
fertilizers. With the high amount of acid rain that falls in Florida (in this State, the average
rainfall pH is 4.5), the calcium and potassium in the N-Viro soil both help increase the natural
soil pH and provide optimum release of plant nutrients. Kiln dust alone is very valuable,
especially to agriculture, but because it is so dusty, it is difficult for farmers to incorporate into
-24-
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TABLE 2
OXIDE ANALYSIS OF CEMENT KILN DUST
(% by weight)
SiO2 13.80
A12O 3.80
FeA 4.50
CaO 43.90"
MgO 0.59
SO 7.80-10.33
PO 0.12
KA 5.80
NaO 0.87
Ti'O, 0.15
Mn2O 0.27
"Total calcium-free lime = 6.9 percent.
-25-
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the soil. When the N-Viro process wets the dust with sewage sludge, it becomes a controllable
substance enhanced by the nitrogen, phosphorous, and organics found in sludge.
N-Viro process alternatives. There are two N-Viro processes. The first process involves raising
the pH of the mixture to 12 for at least 7 days, drying it until the solids exceed 60 percent
while the pH remains above 12, and holding the mixture on site for the balance of the 30 days.
Many facilities choose not to hold sludges on site, even though the odor of the treated end
material is minimal.
The second process combines pH, heat, and drying, to speed up the process. In the
second process, the pH is held at 12 for at least 72 hours and until a minimum of 50 percent
solids is obtained. Calcium oxide contained in the AA raises the temperature of the sludge to
52°C and holds it there for at least 12 hours. This alternative has the three disinfectant killing
mechanisms-high pH, high temperature, and drying. (A forth mechanism is the liberation of the
ammonias, as the pH is raised to 12.)
N-Viro PFRP process steps. The N-Viro process steps are shown in Figure 5. The AA is
delivered to the treatment plant facilities in 24-ton pneumatic conveying vehicles, much the
same as those used to deliver hydrate lime and quick lime. Facilities usually have a standard
lime silo.
\
In the N-Viro process train, the sludge cake is loaded into a hopper by a conveyor or a
front end loader. The AA (cement and/or lime kiln dust and/or lime) are added from the silo.
The sludge and AA are mixed in a pug mill mixer and then held in a heat pulse container for
12 hours to bring the temperature to 52°C. At the end of the heat pulse phase (12 hours), the
mixture is laid out in windrows and air dried. The end product is then stored until use.
Dewatering. The dewatering phase is upstream from the N-Viro process and controls how
efficient the process will be. The typical sludge feed has a solids content of from .5 to 5
percent. The discharge solids content ranges from 12 to 30 percent, with the optimum content
being at least 18 percents solids. The two main process considerations for dewatering are that
-26-
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N-Viro PFRP Process Steps
ALKALINE
ADMIXTURE
SOURCE
N-VIRO
SOIL
MIXING/ ACCELERATED BENEFICIAL
DEWATERING GRANULATION HEAT PULSE DRYING REUSE
Figure 5. N-Viro PFRP Process Steps
-27-
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the higher the percentage of cake solids, the lower the AA dose will be. Also, the polymer
must be alkaline compatible.
Mixing/granulation. The N-Viro process begins with the mixing granulation phase. The
objective is to obtain a complete and uniform mix with a granular discharge. Typical
parameters are an AA dose range of from 25 to 50 percent of the wet weight and a solids
content of the discharge from the mixer of 40 percent or more. For 1000 pounds of sludge
cake, 250 to 500 pounds of AA will be added to the mixture to provide a satisfactory mix and
begin the drying action. Process considerations are a uniform pH and temperature attained by
complete mixing and a good granulation for enhanced drying.
Heat pulse phase. The heat pulse phase reduces pathogens to pasteurization levels. The
temperature must be held at 52°C for 12 hours. The optimal temperature range is from 52 to
65°C. A temperature of over 65°C will begin to create a sterile end product, not a soil, that is
open for reinfestation and will not have nearly as good odor control. Process considerations for
the heat pulse phase are that the alkaline materials are proportioned to provide optimum
heating, storage is designed to minimize heat loss, and odor/ammonia must be controlled.
Accelerated drying. Facilities use accelerated drying to complete the pasteurization process and
reduce the volume and the weight of the material. The windrow facility and equipment should
be well thought out, and dust emissions and odors must be controlled.
*X
Presently, the most difficult aspects of the process are the drying and windrowing
operations. The company is presently investigating different methods of drying, including rotary
kilns, heated surface paddle dryers, and other methods of drying. NES recommends windrowing
undercover for up to 5 days, so that the process does not require an extensive windrow area.
End product. Typically, after one day of windrowing, the end material contains 50 percent
solids, meeting EPA requirements. This product can be used as landfill cover. If the material
is going to be recycled as a soil amendment or liming "product", the final mixture must be in a
form familiar to the user and have a uniform particle size. Therefore, the mixture is windrowed
-28-
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until it contains at least 65 percent solids and produces a granular, more uniform-sized end
material.
The end product looks much like a sandy, loamy soil. N-Viro soils can be stored to
meet distribution schedules, typically for 30 to 90 days. The product stores well without a cover
and stacking conveyors can be used to reduce space requirements. The odor is one that does
not attract flies. The pH can be lowered and nutrients added to enhance the product.
Product uses. N-Viro soil is used as a soil amendment product, sold retail. It is also directly
land applied, used on land reclamation sites, and used as landfill cover material. A
nonagricultural application is its use for turf. It is also used as a topsoil and fertilizer filler.
Many field tests have shown that N-Viro has enhanced the growth of a variety of plant species.
The total beneficial reuse value of N-Viro soil is shown in Table 3. The total reuse
benefit is about $33/ton. The product is not selling for this amount, but the company is
satisfied if the soil sells for $5/ton (as it is in Florida) and the customers are convinced they are
getting $33/ton worth of benefit.
For more information, contact David Sloan (see Appendix A).
-29-
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TABLE 3
N-VIRO SOIL (PFRP) BENEFICIAL REUSE VALUE PER TON
(Assume 50% Sludge Solids; 50% Alkaline Admixture)
Nitrogen at 1.5% $4.50
Phosphorous at 1.5% $6.00
Potassium at 1.5% $3.60
Organics at 25% $10.00
Calcium Carbonate at 30% $6.00
Trace Minerals (S, Mg, etc.) $ 3.00
TOTAL REUSE BENEFIT $33.10
-30-
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ODOR CONTROL FOR COMPOSTING
Terry Crabtree, Smith Environmental Engineering
Broomall, Pennsylvania
Odor is the number-one problem facing the composting industry today, and facilities are
being shut down due to odor complaints from neighborhoods surrounding offensive operations.
Because the components of composting odor problems are similar to many industrial
applications, composting system designs can borrow a solution to this problem from other
industries that have long dealt with volatile organic compounds (VOC). One such technological
solution uses thermal afterburners, which can convert organics to water and CO^ and which
represents the Best Available Control Technology (BACT) for odor control.
Figure 6 is a schematic of an early afterburner system. In the original system, 12,000
scfm of air at 200°F was created by the industrial process. The air entered the burner, which
raised the temperature of the air to over 1,100°F. The solvent from the organics then raised
the temperature further to about 1,400°F. The air was then released into the atmosphere.
One objection to this type of thermal odor control is high operating cost. Raising the
temperature of process exhaust air from typically 100°F to 1,200°F requires significant amounts
of 7uel. Despite this high operation cost, however, plants in the pulp and paper industry and
some other unique industries (such as those making fishmeal) have been using afterburners for
20 years, as this is the only method that removes exhaust odors.
Historical use of afterburners. Figure 1 shows schematics of three basic technologies applied
from the 1960s through the 1980s. The use of afterburners began in the 1960s, when major
odor and VOC offenders used the technology to comply with air quality regulations. The high
VOC content generated by the industrial processed provided significant fuel (BTU) contribution
to the afterburner process.
-31-
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PROCESS
I^OOO SCFM
»
FUEL INPUT TO BURNER
1.400*5
TO ATM.
OJ
FUME INCINERATOR
HEAT ADDED BY BURNER:
HEAT EXHAUSTED TO ATMOSPHERE;
12,700,000 BTU/H
18,800,000 BTU/H
Figure 6. Schematic of an Early Afterburner System
-------
1960's
100°F high solvent
*1,200°F
1970's
750°F
inO°P rnliiY-rit - . . ^
HX
50%
t
v
£ 1,4(OT
1980's
100°F low solvent
170°F
t
»-
HX
95%
t
^
g
J 1,500°F
Figure 7. Schematics of Three Basic Afterburner Technologies (1960s to 1980s)
-33-
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The regulations promulgated in the 1970s restricted emission levels further, requiring 90
percent destruction of VOCs. Additionally, fuel costs became higher, so it was not cost
effective for industries to discharge 1,200°F air. Industries then began to apply heat recovery
methods to remove the odor-causing organics and more economically met air quality
requirements.
In the 1980s, only very low levels of VOCs from process exhausts could legally be
emitted and the issue of odor control became more of a process exhaust concern. For one
polystyrene manufacturing plant, the level of solvent that can be released is only 200 ppm,
which is very low. At peak value, 95 percent of VOCs must be controlled. The process
involves incinerating at 1,000°F, recovering 95 percent of the heat, and emitting 170°F air.
Some facilities are even using the 170°F air to perform drying operations.
New technologies. Some new technologies are regenerative thermal oxidation systems,
recuperative type oxidizers, and thermal oxidizers. Figure 8 is a diagram of the Smith
Regenerative Thermal Oxidation System. In this system, a regenerative heat exchange cycle is
used to alternately heat and cool relatively shallow beds of special ceramic media.
The process begins when VOC-containing process exhausts enter the system and pass
vertically through a heated ceramic bed (the heat exchanger) which preheats the exhausts to
almost final oxidation temperature. These preheated exhausts then enter a combustion chamber
x
where they are further heated and retained at final oxidation temperature to achieve high
destruction efficiency. The hot clean gases exiting this chamber pass through a second ceramic
bed cooled in an earlier cycle. This bed absorbs most of the heat from the gases, cooling them
before discharge to the atmosphere. A third ceramic bed/heat exchanger vessel is
simultaneously being purged of any exhaust still contaminated with inlet VOC emissions to
insure high overall VOC destruction efficiencies for the system. The cycle is repeated,
alternating between the three ceramic beds for heating, cooling, and purging operations. The
quantity and configuration of the bed media are varied to provide for thermal efficiencies of up
to 95 percent. Additional heat exchanger vessels can be used to handle very high exhaust flow
rates.
-34-
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Ceramic Bed/Heat Exchangers
Odorous Air
Retention Chambers
Exhaust Stack
Figure 8. Smith Regenerative Thermal Oxidation System
-35-
-------
Benefits Tor wastewater treatment. One of the benefits of the new technologies is that all the
VOCs are removed, as opposed to just being moved to another media, like that which occurs
with air scrubbers. The equipment also is very fuel and cost efficient and requires little
attention during operation because it is run by programmable controllers.
Table 4 lists average operating costs for the Regenerative Thermal Ondative System,
where the heat recovery value is 95 percent and the amount of fuel consumed is about 1.3
million BTUs per hour. The blowers consume about 120 hp. Operating costs for natural gas
systems would be about $5.00/million BTUs per hour, depending on regional location. Typical
electrical costs are $.06/KWh. Operating the Smith Regenerative Oxidizer 365 days a year, 24
hours a day, will cost about $131,150.
A thermal oxidizer will treat any type of organic material at any level of concentration.
At a sewage composting plant, the level of pinines and turpines (odor-causing byproducts of
wood) vary with the type of wood chips selected. This offers potential cost savings by allowing
selection from a wider variety of woods.
Concerns. Capture of the organics is one critical concern. To remove odors, they must be
captured and sent through the oxidizer. Another concern is that there may be instances when
the air stream from a wastewater treatment plant will require conditioning prior to or after the
\
thermal odor treatment process. For example, if halogenated solvents are present in the
process exhaust, a caustic scrubber may be required after the thermal oxidizer. In another
example, high levels of ammonia in the process would require a water scrubber prior to the
oxidizer.
Initial equipment costs are high and costs will escalate significantly with the air flow
levels. Equipment for a system that exhausts 50,000 to 60,000 scfm could cost $1 million.
For more information about these systems, contact Terry Crabtree (see Appendix A).
-36-
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TABLE 4
AVERAGE OPERATION COSTS
FOR THE REGENERATIVE THERMAL OXIDATION SYSTEM
Process Flow
Process Temperature
Operation Temperature
Retention Time
Normal Heat Recovery
Burner Contribution
Electrical Load (Total)
Typical Natural Gas Cost
Typical Electricity Cost
Annual Operating Cost
(365 days/year; 24 hours/day)
20,000 scfm
100°F
1,500°F
1.0 second
95%
1.92 MM BTU/Hour
120 BHP
S5.00/MM BTU/Hour
$0.06/KW-Hour
$131,150
-37-
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SECONDARY TREATMENT TECHNOLOGIES
-------
AUTOMATED THERMOPHILIC AEROBIC DIGESTION
Kevin Deeny, Junkins Engineering
Morgantown, Pennsylvania
Historically, POTWs have treated sludges using digestion or composting processes that
stabilize the sludge under controlled conditions. Conventional stabilization processes can be
aerobic or anaerobic and destroy about 40 percent of the organic solids with a significant
decrease in the number of attendant pathogens. Conventional systems typically accomplish this
level of treatment within 20 to 60 days, depending on the specific method of treatment used.
Liquid composting. Autoheated thermophilic aerobic digestion (ATAD) is a sludge digestion
process that operates under thermophilic temperature conditions without introducing
supplemental heat. The system relies on the heat released during the digestion process itself to
attain and sustain the desired operating temperatures. Perhaps because of its thermophilic
operating temperature and self sustaining nature, the process was referred to as "liquid
composting" during the early stages of its development.
The ATAD process was the subject of intensive research in the sixties and seventies in
both the United States and Europe. The technology has been widely implemented in Europe,
primarily in the Federal Republic of Germany (FR.G), where approximately 43 full-scale
facilities are in operation. Three installations are known to exist in Canada, two of which are
similar to the FRG version and one of which is a unique system. In the United States
(Connecticut), one full-scale application is being planned.
Technology assessment In 1989, the U.S. EPA Risk Reduction Engineering Laboratory
(RREL) initiated a technology assessment of the alternative ATAD systems implemented in the
FRG. The assessment included visiting a number of facilities to evaluate operator satisfaction
and overall system performance, and interviewing design engineers, system manufacturers, and
the research community.
-39-
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The assessment showed that the most widely used ATAD configuration uses covered insulated
reactors that are normally installed above ground (see Figure 9) and an efficient atmospheric air
aeration system that is considered to be essential for attaining the desired operating conditions.
Typically, facilities use two-stage systems to insure that pathogen reduction meets regulatory
requirements. Reactor temperatures in the second stage are normally in the range of 50°C to 60°C,
and the total hydraulic detention time at design loadings is about 6 days. Volatile suspended solids
reductions ranged from 30 to 50 percent in the facilities evaluated.
The application capacities of the FRG installations range from 3,500 to 80,000 population
equivalents (PE), with more than 70 percent smaller than 15,000 PE. Most facilities are located in
central and southern Germany, in agricultural areas that closely link the technology with the
agricultural use of sludge. A number of studies determined that the system produces an "hygienically
safe" sludge, a criteria category that is required in the FRG for using sewage sludge on agriculture (se
Table 5).
For the 22 facilities studied, installation cost data indicated that the process was generally mor<
cost effective than operating conventional alternatives, even without considering enhanced pathogen
reduction. Operating personnel reported minimal maintenance requirements and noted the simplicity
process operation.
Odors were a particular focus during the site visits due to the increased public sensitivity relat<
\
to locating wastewater and sludge treatment systems in nonrural areas. Typical soil and humus-like
odors were noted in most facilities that were not equipped with odor control systems. One facility w£
noted as odorous during a 30 percent overload condition brought about when grapes were being
processed at a local winery. A present odor control practice for nonrural applications is to use a
compact upflow scrubber (see Figure 10).
EPA prepared a detailed technical report that summarizes the pathogen reduction studies,
operating experiences, design criteria, and costs associated with Autoheated Thermophilic Aerobic
Digestion. Copies of the report can be obtained by contacting Kevin Deeny (see Appendix A).
-40-
-------
Thickener
Supernatant
Reactors
Heat Sludge Sludge
Exchanger Storage Disposal
Supernatant
Figure 9. Flow Diagram of a Two-Stage ATAI) Facility with Heat Recovery
-------
TABLES
PROPOSED CRITERIA AND CONDITIONS
FOR HYGIENICALLY SAFE SLUDGE
IN THE FEDERAL REPUBLIC OF GERMANY
The sludge treatment technology must be proven to:
reduce the number of indigenous or intentionally
seeded Salmonella by at least 10*
render indigenous or seeded eggs oiAscaris
noninfectious.
Sludge sampled directly after treatment must contain:
no salmonella
less than 100 enterobacteriaceae/gm
The sludge treatment technology must be operated within guidelines developed
specifically for the technology. For ATAD these include:
minimum 2-stage configuration
undisturbed (i.e., no feeding) reaction time as
below:
Time >. 23 hours, Temp. > 50°C
Time >. 10 hours, Temp. > 55°C
Time >. 4 hours, Temp. > 60°C
total detention time > 5 days
pH .> 8
-42-
-------
EXHAUST
AIR IN
iitii ii
J i n 11 11
EXHAUST AIR OUT
-» \ p
w-
XX X XXX X A /- X A ^
X X X X FILTERBED < * A A A >
x ^ x x x x XA\
t^X J^ V > LATTICE GRATING/XX**/
PRE-WASHING DEVICE
FAN
t t f t t t t t t t t t t t t t t « t t t
CONDENSATE
Figure 10. Schematic of a Compact Upflow Scrubber (Fuchs Biofilter)
-43-
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CAPTOR STUDY OF MOUNDSVILLE/GLENDALE MUNICIPAL WASTEWATER TREATMENT WORKS
Elbert Morton, West Virginia Department of Natural Resources
Charleston, West Virginia
The "Captor" process is a high biomass biological treatment process for municipal
wastewater, originally developed and widely used in England. In effect, this process transforms
a suspended growth system into an attached growth system through the use of large quantities
of polyester foam pads in the aeration tanks. The pads, 1 inch by 1 inch by 1/2 inch in size,
encourage the growth and adherence of the biomass onto the surface and reticulated
infrastructure of the foam pads. In the Captor basins, primary effluent comes in contact with
the fixed film of biological organisms growing on the pads, which provides organic material food
for the organisms. Based on general food to biomass loading considerations, the volume
requirements of the aeration basin decreases in proportion to an increase in biomass
concentration. In the Captor basins, both biological oxygen demand (BOD5 or BOD) and part
of the secondary treatment process oxygen demand are reduced.
The pads can be adequately mixed with a fine bubble diffuser at 1,100 pads/cu.ft. The
higher oxygen transfer capacity of the fine bubble aeration technology applied to the Captor
process maximizes the potential to substantially increase the biomass concentration. The high
density of pads also allows the system to obtain higher biomass concentrations than those
typically encountered in municipal activated sludge processes.
Another aspect of the Captor process is a unique wasting technique that removes excess
sludge by extracting a certain percentage of the pads from the reactor and passing them
through rollers that squeeze out the waste sludge. Compared to conventional biological
processes, substantially higher dry solids concentrations can be obtained with the wasting
process, thereby eliminating the need for separate sludge thickening.
-44-
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Project history. From 1984 to 1989, the West Virginia Department of Natural Resources
(DNR) studied the Captor process at a 2.35 MOD regional wastewater treatment plant
servicing the cities of Moundsville and Glen Dale, West Virginia, and the surrounding areas.
The U.S. EPA awarded the project with a Step Il/m grant requiring DNR to conduct a field
test before EPA would issue final approval to begin the design.
The project team tested a Captor pilot unit to determine if the Captor process could
meet secondary treatment standards and decrease the required aeration zones. The pilot unit
consisted of a 10 ft. high by 10 ft. wide by 45 ft. long steel tank that included four separate
aeration zones equipped with fine bubble diffusers, an effluent channel, a clarifier with a
hopper bottom, an air lift sludge return, and a scum skimmer. The first aeration zone was
equipped with a pad cleaner and an effluent screen. The pilot plant operated with the Captor
and activated sludge basins in series, and the effluent from the activated sludge compartment
directed to the clarifier. When the process stabilized, flow rates, detention times, pad cleaning,
and other test parameters were varied to determine their effect on plant performance.
Design. Consistent with the findings from the pilot study, the final plant design consists of a
Captor aeration area, followed by activated sludge and secondary clarifiers. Hydraulic detention
time for the Captor area is 1 hour at the average design flow of 2.35 MOD and 2 hours in the
activated sludge area. The system consists of a mechanically cleaned bar screen, an aerated grit
chamber, 2 primary clarifiers, the Captor aeration basin, an activated sludge area, 2 secondary
\
clarifiers, and an open channel ultraviolet (UV) disinfection unit. The sludge is treated by
single primary and secondary anaerobic digesters and two belt filter presses. This system has
two parallel aeration units, and the Captor pad basins make up the first stage of the 2-stage
secondary treatment process.
Plant start-up. The system began operating in June 1989. During its initial phases, several
problems occurred with the influent and effluent screens and the approach to sludge
management. About 2 weeks after start-up, the stainless steel screen separating the Captor
process from the activated sludge unit became clogged and bent, allowing about 4 million pads
to escape into one of the secondary clarifiers. The clogging was attributed to biological growth
-45-
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binding to the screen, which occurred during a peak hydraulic loading after a storm. The
clarifier was shut down, and the pads were removed using a sewer/vacuum truck. A few days
later, the additional flow added to the one operating unit caused the effluent to build-up
enough to bend the screen in this unit, too, although the effluent did not flow over the screen
in significant quantities as a result. The screens from both units subsequently were redesigned
by the manufacturer, Ashbrook Simon-Hartley, and were put back into service by September,
1989. The new screens have additional structural bracing against the concrete tankage.
In mid-September, 1989, the influent Captor screens in one of the units failed,
apparently due to backflow from the effluent screen, the build up of biological mass on the
screens, and inadequate bracing. In October, the influent screens from both units were
removed and not replaced. To limit the amount of biomass on the effluent screens, the State,
engineer, and manufacturer agreed to increase the mixing and aeration in the system to help
the pads act as a scouring agent against the effluent screens. The group also decided that the
effluent screens needed to be mechanically cleaned to remove the biomass build-up, so air knife
scouring devices were added to both units.
After the major repairs were completed in October, the air knives were properly
aligned, the aeration diffusers were repaired, and additional sections of screening were added to
the top of the effluent screen to prevent overflow of the pads. The biological system stabilized
by November, and the UV system was placed into operation December 1. (Prior to this time,
the effluent was chlorinated using the effluent line as the contact chamber.)
The complete sludge handling equipment was not fully operational until November 1989.
The facility experienced problems with the start up of the belt filter presses, preventing sludge
stabilization within a reasonable start-up time. This problem was attributed to operator
inexperience. The operator was also carrying a significant sludge blanket into the primary
clarifier, contributing to the delay in the acceptable operation of the Captor process.
Operation. Table 6 shows BOD5, total suspended solids (TSS), total keldjian nitrogen (TKN),
and fecal coliform count for the plant from December 1989 through February 1990. Based
-46-
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TABLE 6
PLANT EFFLUENT RESULTS FOR THE MOUNDSVILLE/GLENDALE
MUNICIPAL WASTEWATER TREATMENT PLANT
(November 1989 to February 1990)
SUSPENDED TKN
MONTH SOLIDS BOD5 Mg/L FECAL
Avg. 22 31 19 5
Nov. Max. 27 32 18 20
Min. 18 28 19
Avg. 24 27 16 16
Dec. Max. 29 30 17 10
Min. 19 21 14 165
Avg. 21 41 16.8 108
Jan. Max. 27 65 15 319
Min. 17 20 19 11
Avg. 14 30 81
Feb. Max. 20 26 256
Min. 7 34 28
-47-
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solely on the operation data, the system shows the potential to meet secondary wastewater
treatment requirements.
One factor affecting these results is that solids accumulated in the system because the
sludge handling system was not stabilized. Since January 1990, excess amounts of solids have
been removed from the plant via the belt filter presses and disposed of in a landfill. The
average suspended solids and BOD5 loading rate to the primary clarifiers is shown in Table 7.
Excess solids still must be removed from the system due to the amount of loading from the
digester.
Another operational problem is due to the biological makeup of the system. Because
the mixed liquid suspended solid (MLSS) of the activated sludge zone has varied from 2,000 to
5,000 mg/1, system operators have found it difficult to obtain and maintain a steady biological
growth or establish a standard return activated sludge or a waste sludge. The operator has
found that the most effective operation rate for the plant is between 3,000 and 3,500 mg/L.
A third operational problem was the excessive growth of carchesium protozoan in
December 1989, which appeared as a gray slime on the exterior of the sponges. To eliminate
the overgrowth of this organism, the dissolved oxygen has been lowered enough to cause them
to die off, and aeration and mixing was enhanced to scour the organism off the pads. These
methods appear to be working, but it is still not known which method contributes more to the
*\
die off.
The Captor sludge vortex pumps also have been problematic. The pads become
squeezed between the impeller and the wall of the pumps, binding the impeller and preventing
the pads from being cleaned. To solve this problem, the system engineer is considering either
changing the pump or the present operational mode to provide a backflush of the pump or an
alternate method of removing the pads.
Conclusions. At this time, the success or failure of the Captor system cannot be judged.
Based on the monitoring results, the system should be able to function as a secondary process if
-48-
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TABLE?
AVERAGE SUSPENDED SOLIDS LOADING RATES TO THE PRIMARY CLARIFDZR
OF THE MOUNDSVILLE/GLENDALE WASTEWATER TREATMENT PLANT
(November 1989 to February 1990)
BOD5
SS Mg/L Mg/L
November 1989 477 355
December 1989 476 341
January 1990 544 419
February 1990 400 345
-49-
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system designers can address the problems encountered. A detailed analysis of the site
specifications criteria must be considered.
Based on the limited data available, the Captor process may not be cost effective for a
new secondary plant, but it may be suitable for upgrading an existing plant where space for
expansion is limited. Detailed operation and maintenance costs have not yet been examined.
To obtain a more complete description of the system and project, contact Elbert Morton
(see Appendix A).
-50-
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PHYSICAL-CHEMICAL PROCESS PROVIDES
COST-EFFECTIVE SECONDARY WASTEWATER TREATMENT
Robert D. Sparling, City of Tacoma Sewer Authority
Tacoma, Washington
In September 1986, the City of Tacoma, Washington, began an extensive investigation
on the benefits of using a physical-chemical process to achieve secondary treatment at its North
End Wastewater Treatment Plant. This investigation was prompted by the results of previous
engineering studies that indicated that the existing plant would need to be demolished and a
new plant would need to be rebuilt to achieve secondary treatment with a conventional
biological process. Before choosing this extreme option, the city wanted to investigate
alternative secondary treatment processes that would require less construction.
Pilot test. The city and the State of Washington Department of Ecology conducted full-scale
pilot tests at the North End Plant from January 1987 to July 1989 to collect comprehensive
operational data on a physical-chemical process under actual conditions. Prior to this time, the
plant had been only a primary treatment facility. Wastewater flows at the plant averaged 4.5
MOD, providing wastewater treatment for an estimated sewer population of 43,750. A
schematic flow diagram of the pilot plant is shown in Figure 11. Table 8 is a summary of
existing plant waste loads.
For the pilot tests, temporary chemical storage containers, piping, and chemical feed
equipment were installed at the plant. Alum and various polymers were then added to the
existing primary treatment processes at locations as shown in Figure 11. The plant was
operated without making any other modifications to the physical structures. Throughout the
test period, daily component samples were analyzed for BOD, soluble BOD (SBOD), and
suspended solids (SS). The average 30-day concentration and removal efficiencies are shown in
Table 9.
-51-
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MANUAL
BYPASS
SCREEN
the Tacoma, Washington,
-52-
-------
TABLE 8
SUMMARY OF EXISTING PLANT WASTE LOADS AND STATISTICAL ANALYSIS
BOD
Annual Average (AA)
Average Dry Weather (ADW)
Average Wet Weather (AWW)
Maximum 30-day
Maximum 7-day
SBOD2
Annual Average
Average Dry Weather
Average Wet Weather
Maximum 30-day
Maximum 7-day
Suspended Solids
X
Annual Average
Average Dry Weather
Average Wet Weather
Maximum 30-day
Maximum 7-day
Calculated
Concentration
(mg/L)
163
161
166
185
152
47
46
49
54
81
166
167
165
234
259
Observed
Plant Flow
(MGD)
4.5
4.2
4.9
5.1
9.2
4.5
4.2
4.9
5.8
4.5
4.5
4.2
4.9
4.9
7.2
Observed
Loading
(#/dayl)
6,100
5,540
6,780
7,850
11,700
1,770
1,610
2,000
2,600
3,070
6,230
5,850
6,730
9,550
15,540
'Observed loadings of plant influent.
Defined as passing 0.54 micron filter.
-53-
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TABLE 9
PILOT TEST EFFLUENT BOD, SBOD1, AND EFFLUENT SS
Annual Average
Dry Weather
Wet Weather
Maximum Month
Effluent
mg/L
28
27
29
30
BOD
Percent
Removal
82
83
82
80
Effluent
mg/L
22
10
24
27
SBOD1
Percent
Removal
53
59
51
50
Effluent
mg/L
12
11
13
16
SS
Percent
Removal
93
94
92
89
1 Defined as passing a 0.54 micron filter
-54-
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The toricity of the physical-chemical process effluent was also compared to that of a
conventional biological secondary process. Both trout and Daphnia bioassays were performed
using effluents from both the North End Plant and a nearby secondary plant that uses a
biological treatment process. These tests indicated that there was no significant difference in
trout or Daphnia mortality between the two plants.
The results of the pilot test demonstrated that a physical-chemical process could
sufficiently remove organic material and suspended solids equivalent to secondary treatment. In
terms of efficiency, the physical-chemical process reduces suspended solids well below the
regulatory limit of 30 mg/L or 85 percent removal. On an annual average, the process removed
92 percent of the suspended solids, which is about one-half of the total secondary discharge
allowed. The reduced solids discharge is significant in terms of total potential for solids
deposition and toxicant removal. This conclusion was reached without the full benefit of
accurate chemical dosages and optimum coagulation and flocculation because these data were
not possible to collect using the temporary equipment installed for the test period.
The physical-chemical process removed an average of 73 percent of priority pollutant
metals compared to 55 percent for the activated sludge process. The total mass emission of
toxicants by a physical-chemical process would be approximately 50 percent of that expected
from secondary permit limits.
New plant construction. Based on the data, in 1989 the City of Tacoma began building a
permanent physical-chemical treatment plant at the North End site that includes a new chemical
feed building. Only relatively minor modifications were necessary. The new facility allows for
maintaining accurate chemical dosages during the process regardless of wastewater flow.
Since completion of the new chemical feed building, Tacoma's North End Plant has
achieved secondary treatment using a physical-chemical process. The city has demonstrated that
they saved significant capital, operation, and maintenance costs by using this process compared
to conventional biological secondary processes.
To obtain a complete report with extensive application and operational data on using a
physical-chemical process, contact Robert Sparling (see Appendix A).
-55-
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BIOLAC TECHNOLOGY EVALUATION
Karl Scheible, HydroQual
Mahwah, New Jersey
Biological Aeration Chains (Biolac) constitute an extended aeration system first used in
Europe. The technology was introduced into the United States in 1986, and since that time, a
significant number of Biolac plants have been installed in this country. The U.S. EPA Office of
Municipal Pollution Control (OMPC) sponsored a study to assess this technology and problems
that may have been encountered at several Biolac facilities.
The Biolac system is an innovative technology for extended aeration. It uses high
efficiency fine bubble aeration and accomplishes mixing with relatively low horsepower (HP)
requirements. Most Biolac systems use integral clarifiers and are generally designed for low
loadings. As a result, the systems have high process stability and BOD, TSS, and NH3-N
removals. In general, Biolac systems have lower capital costs and potentially lower O&M costs
compared to conventional extended aeration systems.
For the EPA study, OMPC surveyed and evaluated Biolac system configurations, plant
operations, operating levels compared to design capacities, problems encountered, and how the
problems were resolved. The study team collected data on system performance (relative to
design specifications) and capital costs. OMPC contacted facilities by telephone or through
direct visits.
System description. Survey results indicate that as of September 1989, 59 Biolac plants are
located in 20 States, and 12 more are being planned. Forty of the operating facilities are
municipal installations, with design flows ranging from less than 0.1 MGD to 54 MGD.
Twenty-five of the municipal plants use clarification and solids recycle (designated as the Biolac-
R), while the rest use flow-through lagoons with no solids return (Biolac-L).
-56-
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The basic Biolac configuration consists of a basin or lagoon equipped with floating
aeration chains (see Figure 12). The chains are made of Wyss fine-bubble diffusers attached to
flexible headers. The diffusers are weighted and hang from a float assembly. Several of these
diffuser/float assemblies are connected and form a chain across the basin, which is anchored to
the basin sidewall. These floating aeration chains oscillate across the basin surface, propelled by
the rising bubbles from the diffusers; this moves the diffuser assembly through the liquid,
thereby mixing and aerating the wastewater simultaneously. When a chain moves to full tension
in one direction, the diffuser assemblies swing slightly and cause the chain to move in the
opposite direction, repeating the oscillation cycle. Some aeration chain systems had been
retrofitted onto existing basins, replacing conventional mechanical or diffused air systems.
The typical Biolac-R system (see Figure 13) uses extended aeration/activated sludge
equipment with integral clarifiers, although retrofits have used existing external clarifiers. The
systems have waste sludge holding basins and often a polishing basin that can be divided by a
floating curtain wall, with the first section aerated and the second section used for additional
settling. The polishing basin is optional but generally recommended for new facilities to assure
effluent quality. The integral clarifier (see Figure 14) has two concrete walls extending from
the basin and a floating partition wall that separates the clarification zone from the aeration
zone. A rake moves back and forth across the clarifier to concentrate the sludge, which is then
removed with an airlift pump. Overflow weirs are generally designed at an average loading of
10,000 gpd/ft.
*\
The Biolac-R systems are often conservatively designed for a hydraulic residence time
(HRT) of 2 to 4 days and a solids residence time (SRT) of 30 to 70 days. BOD loadings range
from 0.03 to 0.1 pounds per pound of mixed liquor suspended solids (MLSS) per day (Ibs
BOD/lbs-d). The design loading rate for the aeration basin is typically 975 Ibs BOD/MG-d.
The diffusers are installed at an average rate of 385/MG. This is equivalent to an air flow of
1,350 scfm/MG, at the typical air flow of approximately 3.5 scfm per diffuser. From a survey of
25 operating Biolac-R plants, the average operating HP is 45 HP/MG, with the plants typically
operating at 40 to 60 percent capacity. Most plants are equipped with 3 blowers ~ one is used
-57-
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Float Assembly
Flemble Hose
00
Down Coming
Flexible
Air Hose
Wyss Diffusers
W&-
Counterweight
pvc
Dilluser Assembly
Concrete skirt/apron'
Figure 12. Biolac Aeration Chnin
-------
Ul
Grit
Chamber
(Optional)
Influent
Screen
Flow
lleaaurlnj
Device
RAS
WAS
Integral 1
CUr liter A
mm** I <
Sludge
Pond
Polishing
Haain (Optional)
I
Effluent
Aerated Unaerated
Figure 13. Flow Diagram of a Typical Hiolac-K System
-------
Waste
Activated <^|
Sludge
Effluent ^
Return Activated
\
~\^~- f
^Tt
XX>
X
Rear Wall of
Aeration Basin
Sludge
^
^
tAAAy^l /«
» v v vv i \;
b_J
k
Float
/O- Coble
ST - - -O- ^
~S
x\ J
V0 III!
Floatlna Partition Wall
for Aeration Batln/Clarifi
Zone Separation
Sludge Distribution and Cone
yj *~-?y
X" ^/^' '^
X^A J-'>T
cation
for
enlration
- Sludge Hopper
Sludge Suction Pipe- PVC pip* located along the length
of the Clanfier Hopper Bottom
Figure 14. Schematic of Integral Biolac-R System Clarifier
-------
full-time, a second is used intermittently on demand, and a third is on standby. The power
usage is about half that required for conventional systems.
The Biolac-L configuration is an aerated flow-through lagoon that eliminates the use of
solids recycle. The Biolac-L systems are generally designed for HRTs of 6 to 15 days, which
are higher than the HRTs of conventional aerated lagoon systems. Polishing basins are used
primarily for solids settling; these have an HRT of 2 to 4 days, with long-term storage capacity
for sludge.
A modified Biolac-R system, known as the Wave Oxidation System, is relatively new
and is operating at one plant in Arkansas to remove nitrogen, as well as BOD and TSS. The
modified system controls and throttles air flow to each chain in progressively alternating groups
of chains, which creates several oxic and anoxic zones. To maintain mixing, after about 15
minutes, the air flow is redistributed and the low air chains receive high air flow and vice versa.
This process forms a dynamic moving "wave" of alternating oxic and anoxic zones.
Table 10 is a summary of performance data from several plants, most of which are new
and operating with BOD removal ranging from 95 to 98 percent and TSS removal ranging from
85 to 95 percent Effluent ammonia concentrations are typically less than 7 mg/L. Excellent
removals were accomplished overall by each of the plants for which performance data were
available.
X
Problems encountered. Many of the problems reported by the surveyed facilities related to the
construction materials used. Various hardware elements corroded and restraining cables showed
excessive wear. The facilities now use stainless steel hardware and 3/16 inch chrome-plated
steel chain cables.
Some of the older Biolac plants experienced problems with the diffusers, which loosened
and filled with sludge, probably due to poor installation and loosening of the attachment clips.
Improper maintenance of diffuser "flexing" also caused the diffuser to clog. This problem can
-61-
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TABLE 10
SUMMARY PERFORMANCE OF BIOLAC PLANTS
% of Design
Plant Flow
Morgantown, KY
Greenville, KY
New Brockton, AL
Edmonton, KY
Fincastle, VA
Lowell, OH
Hanceville, AL
Livingston Manor
Fluent BOD mg/L
TSS mg/L
NH3-N mg/L
58
53
25
39
67
203
88
63
5.1 to
6.7 to
0.1 to
Start
Up
1989
1988
1989
1989
1988
1989
1989
1986
20.8a
34.8a
30.9a
% BOD
Removal
92.3
96.5
95.5
91.1
91.2
91.8
92.0
97.9
% TSS
Removal
85.7
94.7
94.4
89.5
89.7
86.3
92.0
95.3
Effluent
NH3-N
mg/L
0.1
0.5
1.9
3.2
-
6.7
0.8
1.9
a Five plants with no influent data included
-62-
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be resolved through weekly air flow cycling to each chain to effectively exercise the diffuser
membrane.
Some facilities experienced a problem with inadequate mixing and air distribution,
primarily in corner areas, which they resolved by using corner diffusers and cycling the blowers
to increase mixing periodically. The integral clarifier rake switch targets needed to be fine-
tuned, based on problems encountered at the earlier plants. Another problem has been
clogging of the sludge withdrawal line, which may have been due to either insufficient pipe size
or the lack of preliminary screening. Smaller-sized debris (particularly after comminution)
tended to aggregate in the aeration basin and cause clogging in the air lift line.
System costs. The average capital cost for 10 Biolac-R plants installed from 1986 to 1989 was
$1,260,00 per MOD of design flow. These plants are greater than 0.5 MOD in capacity and
treat typical municipal wastewater.
Summary. The Biolac process is a viable, cost-effective system. The existing municipal Biolac-
R systems, operating at about 40 to 60 percent of design flow and loads, are producing
effluents with qualities that are consistent with other extended aeration technologies. Plants are
attaining greater than 90 percent BOD and TSS removals on a consistent basis. Problems with
the equipment related to the materials used for construction, corrosion failure, excess wear,
diffuser clogging and failure, and sludge pump clogging. These problems appear to have been
adequately resolved at the plants that reported problems, and have been accounted for in the
newer plant designs.
The Biolac systems appear to have lower operating costs and less labor requirements,
based on reported average operating horsepowers of only 40 to 50 HP/MG, as compared to
fixed systems that require up to 100 HP/MG.
For more information about EPA's evaluation of Biolac systems, contact Karl Scheible
(see Appendix A).
-63-
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O&M ISSUES FOR POTWS
Hitesh Nigam, EPA Office of Municipal Pollution Control
Washington, D.C.
The National Operations and Maintenance (O&M) Program is a team effort of Federal,
State, and local governments, national organizations, and the general public that provides a
support system for municipal wastewater system operations. The program has assisted many
local governments in their efforts to efficiently operate their wastewater facilities to meet permit
requirements. These programs must be strengthened, however, to respond to current needs and
new challenges facing the wastewater treatment industry.
The main challenges facing the O&M program are a shortage of trained operators in
several areas of the country; control of toxics in wastewater; operation of unconventional
technologies such as natural treatment systems (constructed wetlands, and land treatment
projects); and the competing demand for support for wastewater treatment by other
environmental concerns and public programs.
Goals of the O&M program. The broad goals of the O&M program are to attain and maintain
environmental and safety standards; prevent pollution; protect the wastewater infrastructure
(EPA has spent over $50 billion over the last 15 to 20 years to build systems); promote cost-
X
effective operations; assure an adequate supply of trained personnel; and increase public
support for wastewater treatment.
New program strategy and initiatives. To address the goals and objectives of the O&M
program, the representatives of OMPC, EPA Regional offices, State regulatory agencies, and
State environmental training centers met in Washington D.C. early in 1989 to draft a national
program strategy. The purpose of this strategy is to provide a 3-year framework within which
the EPA and the State O&M support groups can strengthen their activities, coordinate with
other programs, and grow to meet new opportunities and new challenges. After 2 days of
intense discussion, the group recommended that the program implement several initiatives
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within the next 3 years, including wastewater management training, public awareness, program
management, onsite technical assistance, and State training centers
Management training. The wastewater management training initiative will support and develop
training and certification programs for the effective management of wastewater facilities. It also
will help establish and maintain an adequate supply of qualified wastewater personnel. These
goals can be achieved by supporting the development of training curriculum for the operation
and maintenance of conventional technologies and developing a network of expertise through
training center programs. The O&M program will soon begin to train wastewater operators and
provide technical assistance for overland flow projects.
These goals also can be achieved by implementing Youth and the Environment programs
to introduce urban youths to the wastewater treatment field through summer employment at
treatment plants, and developing a partnership with the Department of Labor to incorporate
wastewater training into the Job Corps program. OMPC plans to implement Youth and the
Environment programs in the summer of 1990 in Boston, Atlanta, Washington D.C., Denver,
and Kansas City.
OMPC will continue to hold annual or semi-annual National/Regional meetings with the
States.
X
Public awareness. The initiative on public awareness will inform local government officials and
the general public of wastewater facility O&M issues. It also will inform communities of the
services available through the program and help raise the public image of wastewater
management personnel. One step recommended to achieve these goals is to prepare a
pamphlet targeted to local officials that discusses the importance of operations maintenance and
describes the services available under the program. Another step is to produce public service
announcements for radio and television that urge support for wastewater treatment. Earth Day
and Arbor Day are excellent opportunities for OMPC to promote the O&M program. A third
step is to solicit support through Indian health service and the O&M awards program for the
Indian tribes.
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One additional promotion of the O&M program is the idea of collecting household
hazardous waste at wastewater treatment plants. This activity can provide a useful service to
the community, and make people more aware of where their wastewater treatment plant is.
Program management. The program management initiative will enlist support for strategy
implementation; improve O&M program communication and coordination, internally and with
others; and assure the availability of adequate personnel, financial, and material resources for
program maintenance and growth. The actions necessary to meet these objectives will be to
coordinate representatives from Federal agencies and appropriate national organizations, and
form environmental training centers to coordinate O&M activities among programs.
The program plans to expand the Onsite I Oversight newsletter by broadening the mailing
list, encouraging the contribution of articles, and publishing it quarterly. The office also will
support the electronic bulletin board that links EPA State agencies and State training entities,
and meet with representatives of State and other Federal agencies to develop plans to better
coordinate technical assistance activities. The electronic bulletin board has already proven to be
beneficial to the O&M program.
Onsite technical assistance. The objective of the onsite technical assistance initiative is to
continue to expand the onsite technical assistance program, including the 104(g) program that
assists small communities and Indian tribes in operating their wastewater facilities and achieving
and maintaining permit compliance. The 104(g) program, which has contributed about $1.8
million annually, has been extremely helpful. This effort may be difficult due to declining grant
funds.
To increase publicity and the base of support for onsite technical assistance and foster
coordination of technical assistance programs at Federal and State levels, the O&M program
plans to investigate other potential sources of funding, including other municipalities, States, and
Federal agencies.
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The program also plans to promote onsite assistance as a tool to maintain compliance
and prevent pollution and expand technical assistance services to include financial management,
plant startup, and maintenance management. If possible, the program will expand technical
assistance services to include Indian tribes and other Federal facilities. The Department of
Energy already has shown an interest in obtaining technical assistance.
The onsite technical assistance program will be publicized through the O&M awards
program. A new awards category is The Most Improved Treatment Plant," which will
recognize an outstanding trainer and facility that has received onsite assistance. The awards are
acknowledged at the WPCF conference each year.
State training centers. To expand State training centers, the O&M program will complete,
update, and expand the environmental center directory to include every State and special areas
of wastewater expertise. There are 39 State training centers at this time. The electronic
bulletin board system will be used to facilitate communication and networking among the
training centers.
This initiative will also promote, where appropriate, multi-disciplinary environmental
training at the State centers and the participation in special sessions at the Rural Water 2000
Conference to publicize State training centers and form linkages with the Rural Community
Assistance Program (RCAP) and other programs.
»\
OMPC sent the draft O&M strategy to EPA Regional offices, State regulatory agencies,
and State environmental training centers for comment. The strategy will be finalized in mid-
1990. For more information, contact Hitesh Nigam (see Appendix A). See Appendix B for a
list of National O&M contacts, and Appendix C for a list of Regional and State O&M
Coordinators.
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DENTTRIFICATION USING SUBMERGED ROTATING BIOLOGICAL CONTACTORS
A CASE STUDY
Phillip K. Feeney and Charles E. Bucks, Post, Buckley, Schuh, & Jernigan, Inc.
Orlando, Florida
In February 1982, the City of Orlando, Florida dedicated the Iron Bridge Road Regional
Water Pollution Control Facility, a 24-MGD advanced wastewater treatment plant. The facility
was designed to produce an effluent quality of 5 mg/L BOD, 5 mg/L TSS, 3 mg/L TN, and 1
mg/L TP (5/5/3/1) using rotating biological contactors (RBC), alum precipitation, and tertiary
filtration. Figure 15 is a flow diagram of the facility as designed. In this system, the
denitrification process follows the secondary clarifiers (where alum is added for phosphorus
removal) and precedes the Automatic Backwash (ABW) Filters''.
At the time the facility was dedicated, it was the largest in the country using RBC
technology, with 171 shafts for carbonaceous removal and nitrification and an additional 42
shafts for denitrification. Each shaft is about 15 ft in diameter. The carbonaceous/nitrification
shafts are 25 ft long and contain from 100,000 to 150,000 ft2 of effective surface area. The
denitrification shafts (SRBC), which operate completely submerged, are 35 ft long and contain
about 100,000 ft2 of surface area.
\
During the first year of operation, when the denitrification units were operated, there
was a rapid loss in denitrification and a rapid clogging of the tertiary filters, resulting in a
steady increase in backwashing times. In February 1983, the denitrification unit was shut down
until pilot studies could be performed. The city hired the consulting engineering company of
Post, Buckley, Schuh, and Jernigan, Inc. to assist in optimizing the plant's performance.
Although the plant experienced several problems with additional unit processes in both
the liquid and solids processing trains, this paper summarizes the problems the plant
experienced with the denitrification unit process.
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v£>
Figure 15. Original Iron Bridge Wastewater Treatment Plant Process Flow Diagram
-------
Early pilot tests. In March 1983, the RBC manufacturer, Envirex, Inc., began a series of
onsite pilot tests to identify why the attempts to achieve satisfactory denitrification failed.
Envirex ran two treatment units, one to receive effluent directly from the
carbonaceous/nitrification RBCs, and the second to receive clarifier effluent. A methanol
carbon source was added to both units. Within 2 to 4 weeks, denitrification was established in
the first unit, while the other produced only minimal results. Envirex concluded that the
denitrification was inhibited by a lack of phosphorus. When phosphorus was added to the
second unit, satisfactory denitrification was accomplished. This study was able to establish that
the rate of denitrification, sludge production, and the required methanol dosage were dependent
on phosphorus addition.
Initial plant modifications. In December 1983, after the city added a phosphoric acid feed
system and increased the shaft speed in all the basins from 1.6 rpm to 5 rpm to improve mixing,
the denitrification process was restarted. Several weeks later, total nitrogen was reduced to 6.0
mg/L, although system operators experienced problems with the final filters (backwashing times
approached 24 hours/day and some filter bypassing was required). The filters were dismantled
and cleaned, the underdrain system reinstalled, and new filter media added, and the
denitrification process was restarted in June 1984. One month later, the plant met its effluent
requirements of 5/5/3/1, but this only occurred one time, again due to final Filter malfunctions.
The plant discontinued using the denitrification process in September 1984.
X
Environmental Elements Corp., the filter manufacturer, determined that the nitrogen gas
was affecting filter operation and that stripping the fine gas bubbles from the waste stream
would improve filter operation. To overcome the problems associated with the nitrogen gas
and/or denite solids, the seventh SRBC shaft was removed and converted into an aeration bay
with the installation of an air diffusion system. This modification allowed the "degasified" SRBC
effluent to be fed directly to the final filters. A second more comprehensive process flow
modification, called the "Denite Pumpback" system, was also developed through pilot tests,
whereby, in addition to the degas aeration bay, the SRBC was hydraulically placed between the
RBCs and the clarifiers (see Figure 16). This arrangement allows for the removal of minute
nitrogen gas bubbles, preventing discharge to the final filters; clarification of the denite solids
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MMIVJUOM
-» re at uD*4 4«eo*«*r »r*raA4
MUM* MUOW aimno
rrnux jnottuit HMD,** roux
Z-t M6D HOV-OtJCtO
TlteaTMCUT FflCILIlY
Figure 16. Iron Bridge Denite Pumpback Process Flow Diagram
-------
before discharge to the final filters; and elimination of the need to add supplemental
phosphorus.
Denite pumpback pilot test The denite pumpback pilot tests were conducted as a result of a
U.S. EPA Consent Decree requiring Orlando to conduct a 4-MGD pilot test program,
determine if reconfiguration of the plant flow would allow the existing facilities to achieve
permit limits, and construct the modifications indicated as necessary by the testing program.
Specific objectives included determining the required methanol addition and nitrate removal that
might be expected from the denite process; allowing long-term operations of the denite process
under controlled conditions for full development of process biology; examining clarifier
performance and chemical requirements for phosphorus removal and solids settling; evaluating
filter performance when operated in conjunction with the denite process; and evaluating overall
system performance, flexibility, and reliability.
Testing the denite pumpback configuration consisted of pumping RBC effluent directly
to one of the denite RBC trains, pumping the denite effluent back to one of the secondary
clarifiers, and then pumping the clarifier effluent to one of the plant filters. The system was
operated with full-scale equipment for about 6 months beginning in January 1985. The tests
indicated that the system would work at optimum performance if more methanol was added
than the amount stoichiometrically required (1-1/2 to 2-1/2 the theoretical range).
X
Pilot test operators slowly increased the methanol feed rate until the beginning of
February 1985, when the feed rate was set at 57 mg/L. Because BOD limits were being met
for the plant effluent, the methanol feed rate remained at this level to observe the performance
of the denite system. The plant achieved complete denitrification in mid-February 1985, at
which time operators initiated 24-hr composite sampling.
Denitrification biology versus process efficiency. Operation and the efficiency of the
submerged RBC denite process was complicated by the growth of nondenitrifying filamentous
organisms in the denite tank and on the denite media. These organisms, the growth of which
can be stimulated by short chain organic compounds such as methanol, are successful
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competitors for organic substrates in low dissolved oxygen environments. Excessive growths in
the Iron Bridge nitrifying RBC system are routinely handled by using air to purge the shafts.
Air headers were placed under each shaft and connected to a central air distribution system.
The solids are captured in the plant clarifiers and air flow is returned to normal levels. Shifting
the methanol feed point shifts the position of both effective denitrification and filament growth
in the train.
Pilot test results and conclusions. Effective operation of the system for evaluation purposes
was not considered to have begun until early April 1985. Operating averages for the system are
summarized in Table 11.
The RBC process functioned efficiently, producing average effluent NH3-N levels ranging
from 1.0 to 2.0 mg/L. By eliminating the need to add phosphorus and allowing high methanol
feed rates without increasing BOD, the system continued to reduce ammonia and produce
sufficiently low levels of effluent NOX-N to achieve permit limits for total nitrogen (TN). The
filter was biologically active, removing nitrates, TKN, BOD, and TSS. Data for August 1985,
which include results for increased flow, also indicated an improvement in the removal of NOX-
N and a reduction in ammonia. Operating with a repaired filter in May, the pumpback
treatment configuration allowed the 4-MGD process to achieve simultaneous compliance with
discharge limits for effluent BOD, TSS, TN, and total phosphorus (TP).
X
The results indicate that the pumpback treatment configuration was a viable alternative
to the original plant flow scheme. The system allowed the denite process to be operated
without fouling the ABW filters, which remained in continuous service without bypassing or
cleaning for over 3 months and met TSS permit limits for 5-1/2 months. The study also
confirmed the results of other testing in determining that the Iron Bridge WPCF must function
as a unified system with each process performing effectively to achieve permit compliance.
Full-scale operation. Based on the pilot test results and pursuant to the Consent Decree, full-
scale modifications were designed, constructed, and placed into operation in late November
1986. Within 10 days of methanol addition, sufficient denitrification was established to achieve
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; TABLE 11
IRON BRIDGE WWTP DENITE PUMPBACK PILOT STUDY
MONTHLY AVERAGES AND RANGES
PMMCTER
FUM,NH>
MERMX
ME
no,^/i
MME
MME
IN,.,/!
MME
WENME
MME
MME
MME
ND2-N,*/!
MME
HETWML FEED
mn
IfTft *WC
MME 1
1
FEMUMY
RK OENITE aMIFIER FILTER
EFFLUENT EFFIUENT EFFIUENT EFFLUENT
3.7 17 3.7 17
3.5-4.1 3.3-4.1 3.5-4.1 3.5-4.1
SI 144 12 9
38-48 13-424 4-28 3-14
87 298 21 II
*8-lt* 18-28*1 7-44 3-34
19.3 15.4 11.5 11.8
18.8-22.4 18.4-17.8 9.4-112 8.5-119
4.4 7.7 8.5 8.3
5.5-8.5 5.8-18.8 8.4-8.7 8.2-8.5
3.2 3.2 4.7 4.4
3.8-4.5 3.7-8.2 17-5.7 3.3-5.4
9.2 3.4 5.4 5.8
8.3-9.9 1.2-7.8 2.7-4.9 2.*-«.7
8.9 8.4 8.3 8.2
8.4-1.6 8.2-8.6 8.4-8.6 8.2-8.2
41.9 --
33.4-43.1
NMO4
MC DENITE OMIFIER FILTER
EFFIUENT EFFIUENT EFFLUENT EFFLUENT
19 19 19 3.9
2.5-4.7 2.5-4.7 2.5-4.7 2.5-4.7
78 64 14 9
28-198 28-128 1-42 2-25
134 129 24 9
45-341 44-233 6 52 2-22
23.5 13.9 4.5 4.3
18.1-35.4 14-24.5 2.8-12.3 18-14.8
5.8 4.8 8.9 8.8
1.6-18.8 1.9-8.1 8.8-3.2 8.8-11
6.4 3.8 19 *.«
1.4-14.6 8.6-18.1 8.1-8.9 8. 1-11.3
4.9 8.7 8.6 8.8
1.8-14.7 8.1-3.9 8.1-1.8 8.8-4.9
I.I 8.3 8.3 8.1
8.2-3.2 8.4-1.8 8.8-1.2 8.8-4.9
42.3
8.8-43.5 1
1
RK DENITE aMIFIER FILTER
EFFIUENT EFFIUENT EFFLUENT EFFIUENT
19 19 3.9 19
71 72 II 4
32-184 42-124 4-27 1-13
128 113 28 4
21-257 75-191 18-39 2-9
21.5 II. 1 4.1 18
I4.4-JI.8 4.4-15.* 1.8-4.7 8.9-4.3
3.4 3.2 1.9 1.6
*.8-4.* 4.1-4.3 8.2-3.3 8.2-5.3
1.4 8.9 8.7 8.9
8.2-2.4 8.5-1. 5 8.1-1.5 8.2-2.1
18.2 8.9 8.7 8.5
7.4-12.3 8.2-1.4 8.1-1.2 8.8-1.2
8.7 8.7 8.6 8.4
8.2-1.3 8.4-8.9 8.3-1.8 8.1-1.1
28.1-44.8 1
1
mi
MX OENITE OMIFIFR FILTER
EFFIUENT EFFIUENT EFFLUENT EFFLUENT
4.4 4.8 4.8 «.8
~ 9 4
2-18 1-4
149 98 27 5
78-298 38-242 13-64 2-18
4.3 14
2.4-4.5 1.8-4.3
4.7 4.5 8.4 8.6
8.2-2.1 8.3-1.5
2.1 I.I 4.6 1.8
1.2-4.4 8.3-13 8.1-1.9 8.2-2.2
8.8 8.7 1.8 8.9
4.4-18.3 8.8-1.3 8.8-2.7 8.1-1.7
4.3 8.5 8.7 4.3
8.5-1.3 8.1-4.8 4.3-1.3 8.1-4.9
42.8
44.2-57.2
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TABLE 11 (cont.)
MMNETER
ROU,N0D
MERME
WE
MERRK
ME
MERRK
ME
MERRK
TP.BJ/I
MERRJE
ME
MERRK
ND3-N,*/!
WE
WE
urnwa. FED
lav
ME I
JUNE
RJC KNITE OMIFtER FILTER
EFRUENT EFRUENT EFRUENT EFRUENT
4.* 4.» 4.» 4.*
XM.9 X9-4.9 X9-4.9 X9-4.9
19 1
HT7 2-U
129 71 23 4
39-492 29-123 9-123 1-19
4.4 X2
. 14
9.I-X4 9.1-9.1
1.9 1.2 l.l l.l
.7-4.6 9.2-2.3 9.1-1.9 9.2-3.4
9.9 1.3 1.2 9.t
7.9-19.8 9.t-4.l 9.2-3.7 «.2-l.4
.3 9.5 9.4 9.3
.9-9.1 9.1-1.2 9.1-1. J 9.1-1.4
S7.«
37.2-7t.«
JULY
RK KNITE CLMtFTER FRIER
EFFLUENT EFRUENT EFRUENT EFRUENT
4.M.9 4.M.I 4.*4.9 4.M.9
7 3
1-19 1-12
III 73 21 2
31-217 1-171 3-73 1-4
4.3 2.1
2. MM 1.9-3.9
1.2 9.3
9.3-1.9 M-9.4
1.4 t.t 9.3 9.3
«.4-2.t 9.1-1.9 i. 1-1.2 M-1.9
9.3 17 «.1 t.*
7. MM M-l. 4 .J-I.7 «, |-|.f
.t (.4 t.4 9.1
9.4-9.7 M-«.9 i.Z-9.7 9.1-9.9
57.2
1
1
BIT
RJC KNITE CLMIFIER FILTER
EFRUENT EFRUENT EFRUENT EFRUENT
4.1 4.1 4.1 4.1
4.9-4.9 4.9-4.3 4.9-4.3 4.9-4.3
9 4
3-17 1-9
139 K 23 3
17-W lt-«9l 9-192 1-9
4.4 2.1
2.7-i.S 1.4-3.3
I.I 9.4
ilt-2.3 9.2-9.1
2.3 1.9 l.t I.I
1.4-3.9 9.2-S.t 9.3-C.9 «.3-«.4
.( 9.9 9.1 9.4
19-19.1 9.3-9.1 9.1-2.9 9.1-9.1
9.7 9.3 9.4 9.2
9.9-1.9 9.l-9.t 9.1-9.1 9.l-«.t
3C.I
39.t-37.t 1
1
RJC KNITE ORRIFIER FILTER
EFFLUENT EFRUENT EFRUENT EFRUENT
4.4 4.4 4.4 4.4
4.9-t.9 4.9-t.t 4.9-4V9 4.9-4.9
19 4.9
139 n 29 3
191-234 39-134 14-33 2-4
4.4 2.1
2.9-4.4 2.9-X9
* 1.2 9.t
9.9-1.7 9,2-1.1
2.» I.I 1.9 1.2
9.9-X9 9.1-^.1 9.2-1.9 lLt-2.4
7.4 9.7 9.1 9.3
5.5-45 9.4-1.1 9.2-1.3 9.2-9.7
9.1 9.3 9.3 9.1
9.t-l.( «. 1-9.1 9.1-1.9 9.1-9.2
3B.2
-------
the desired effluent total nitrogen limit of 3 mg/L. Effluent BOD was also brought under
control, and by mid-December, the plant was meeting its four primary effluent parameters.
Table 12 is a summary of operating performance of the facility for January to July 1987.
Discounting the impacts of a toxic industrial discharge in February and a record flow in March,
the plant achieved its effluent requirements. Breakpoint chlorination was used to help trim
effluent ammonia and has contributed greatly to the consistent quality of the effluent.
To obtain more details on the pilot test, operational data, problems encountered, and
costs of this project, contact Phillip Feeney (see Appendix A).
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} TABLE 12
IRON BRIDGE WPCF 1987 OPERATING RESULTS
-4
-4
January
February
March
April
May
June
July
Average
Flow
(MGD)
21.6
22.9
23.9
28.6
24.0
22.6
21.1
23.5
BOD
(mg/L)
3.6
6.6
4.7
5.1
3.8
3.6
3.0
4.3
TSS
(mg/L)
2.6
5.4
3.3
3.2
4.0
2.1
2.0
3.3
NH3-N
(mg/L)
0.5
0.5
0.6
2.1
0.8
0.7
0.5
0.8
TKN
(mg/L)
1.1
1.1
1.2
2.6
1.2
1.2
1.1
\A
TN
(mg/L)
2.8
2.7
2.8
4.3
1.9
1.8
2.0
2.6
TP
(mg/L)
0.2
0.4
0.2
0.2
0.2
0.3
0.2
0.2
Limit
24
2.5
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OVERVIEW OF THE NATIONAL CSO STRATEGY
Harry Thron, EPA Office of Water Enforcement and Permits
Washington, D.C.
Combined sewer overflows (CSO) are flows that do not reach POTWs for treatment.
Under conditions of heavy rainfall, CSOs discharge sewerage, industrial waste (in industrial
areas), and rainwater directly into surface waters without any treatment. CSOs may create
serious violations of water quality standards, can close beaches and shellfish beds, and create
navigational hazards.
There are approximately 20,000 combined sewer overflows in the country, originating
from about 1,150 systems. The total number of NPDES permits in existence now for major and
minor industrial and municipal dischargers is 62,000. Thus, CSOs potentially represent one-third
of the permitting workload in the NPDES program.
Due to other priorities, such as dealing with industrial dischargers and POTWs in
attaining secondary treatment levels, EPA's Office of Water Enforcement and Permits (OWEP)
has recently begun to address the problem of combined sewer overflows. Based on the level of
technology that will be needed to deal with CSOs, the Agency, Regions, States, and consultants
wil^need a significant amount of resources to deal with this problem. Even though finances are
limited and diminishing, compliance with CSO permits will be required. Unpermitted CSOs are
illegal discharges and must be permitted expeditiously or eliminated.
National CSO strategy and permits. OWEP has initiated a national CSO permitting strategy
as part of the NPDES permit program, to minimize the impacts of CSOs on water quality and
human health. The strategy insures that CSOs occur only as a result of wet weather (dry
weather overflows are prohibited). The purpose of the strategy is to bring all CSOs into
compliance with the applicable State water quality standards and technology-based requirements
of the Clean Water Act, including best practicable, control, and available technologies (BPT,
BCT, and BAT). CSOs are not subject to secondary treatment.
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CSO permits apply to either the collection system (the POTW permit), or individual
CSO dischargers (individual permits). Since EPA has not developed any effluent guidelines for
CSOs, best professional judgement (BPJ) should be used to establish permit limits. This means
that the CSO permits will be complex, difficult, costly, and controversial.
State CSO strategies. By January 15, 1990, States needed to develop and submit to EPA CSO
strategies. For this process, the States were supposed to identify their CSOs, determine the
permit status of each one, and set up programs to establish priorities for CSOs that are
inadequately permitted (most CSOs are unpermitted or inadequately permitted). Most States
have complied and have submitted CSO strategies. However, some strategies were deficient
and some States do not know where their CSOs are. March 15 was the deadline for approving
the State strategies. Without the basic inventory of CSOs, it is impossible to proceed with a
meaningful program to permit CSOs.
State CSO strategies must include an adequate O&M program, a plan for maximizing
the collection system for storage, a schedule for activities such as periodic sewer flushing, a
prohibition of dry weather overflows, and the like. The strategies should also include provisions
for upgrading pretreatment programs. Control measures include sewer rehabilitation, best
management practices (BMPs) (qualitative O&M-type controls), construction, and sewer
separation in areas of urban development or redevelopment.
X
EPA is presently writing a guidance manual that will help States understand CSO permit
requirements. The document relies heavily on the WPCF manual of practice issued in October
1989.
CSO Costs. CSO controls are costly and funding is limited. There are a few mechanisms
available, however, to fund CSO improvements, including the 20 percent governor's
discretionary set-aside and the State Revolving Fund (SRF). In many cities, stormwater
management utilities have been developed to address stormwater problems, including CSOs.
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To date, 21 judicial actions have been taken against CSOs, a figure that will likely
increase in the 1990s due to the implementation of EPA's CSO strategy. Developing a viable,
flexible program to solve the problem requires the collaboration of OWEP, OMPC, R&D,
Regions, States, and those in private industry, academia, and professional organizations. If EPA
effectively implements the CSO strategy, after 20 years of benign neglect, CSO discharges can
be controlled and water quality benefits should be realized.
For more information on the National CSO Strategy, contact James Taft, U.S. EPA,
OWEP, (202) 475-9536.
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COMBINED SEWER OVERFLOW (CSO) MANAGEMENT IN EPA REGION I
Richard Kotelly, U.S. EPA, Region I
Boston, Massachusetts
The first serious attempt the U.S. Congress undertook to clean up our nation's waters
occurred with the enactment of the Clean Water Act Amendments in 1972. Since that time,
the Federal government has appropriated and expended billions of dollars for the construction
of publicly-owned treatment plants to treat sanitary and industrial wastes. Direct industrial
dischargers have also spent significant amounts of monies to comply with the effluent guidelines
enacted by the 1972 Act.
Noticeable improvements in the quality of our rivers and streams have taken place. Fish
kills caused by the discharges of inadequately treated sewage in urban and industrialized areas
are less frequent. Yet, despite some obvious gains in the abatement of water pollution, other
visible problems have surfaced to challenge the environmental regulators. In many parts of the
country, the desired or mandated improvements in water quality have not been attained.
National attention is currently focusing on storm-related pollution in the form of storm sewer
discharges and especially combined sewer overflows (CSOs).
Combined sewer overflows. Combined sewer overflows are one of the oldest sources of water
pollution that affects the intended use of our waters. Combined sewers are collection systems
r -\
that convey both sanitary sewage and stormwater, typically found in older cities, especially in the
northeast, the upper midwest, and in the Northern Pacific States. Typically, WWTP systems
collect and carry dry weather flows, primarily sanitary and industrial waste, to the treatment
plant. During storms, however, the combined flows may exceed the sewer and/or the treatment
plant capacity. When this occurs, the systems discharge excess flows directly to surface waters
at one or more overflow points in the system. Figure 17 shows a combined sewer system.
Overflows can contribute a significant amount of organic material, nutrients,
microorganisms, oil and grease, metals and other toxic substances into the receiving water.
Depending on the nature of the receiving waters, overflows can have a variety of effects, from
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Excess Wet Wealhcr Flow
lo Overflow Plan!
Dry Weather Flow
lo Interceptor
Domatitlcahd Industrial Waste
StorRlwater
Interceptor to Deer Island
Waslewater Treatment Plant
Figure 17. llustration of u Combined Sewer System
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serious to very minor. The strategy to control these overflows and the cost of complying with
such controls represent a major challenge to the regulatory agencies and to the affected
communities, respectively.
Region I approach. Region I (the New England States) began to deal in earnest with the
combined sewer overflow issue in the early to mid-1980s. A number of major permittees in the
Region, such as Boston, Lynn, and New Bedford, Massachusetts; Providence, Rhode Island; and
Portland, Maine, all had NPDES permits that needed to be reissued. In addition, there were
150 other communities in New England that were identified with CSO systems. When the
permits were reissued, EPA made clear that all CSOs are point discharges subject to the
requirements of the CWA This means that each discharger must meet technology-based
requirements and water quality standards.
The difficulty hi dealing with CSO regulations is not in knowing what the requirements
are, but how they should be interpreted by the consultants hired by the communities to design
treatment systems. It became clear to us in the Region that we had no clear guidance to offer
communities on how to deal with CSOs. Because there was only a limited amount of money
available for the correction of CSO problems, a national policy had not yet been formulated.
The closing of beaches along the East Coast due to the discharge of medical debris might have
been the drastic signal that finally galvanized the public to demand that the government (EPA)
"do something" and create a sorely needed national policy on CSOs.
>
Because EPA headquarters had no policy, the Region formed a task group made up of
permit writers, water quality standards experts, lawyers from our Regional Counsel's Office, and
others to develop a Regional policy. After countless internal meetings and meetings with the
six New England States, the Region finalized its policy in October 1987. Nothing in Region I's
policy was contradicted by the National Policy which was issued 2 years later. Some highlights
of Region I's CSO policy are as follows.
All dry weather overflows must be eliminated. CSOs are point sources subject to
both the technology-based and water quality-based requirements of the CWA
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Every effort must be made to eliminate CSO discharges from critical use areas
such as drinking water sources, beaches, and shellfishing areas.
It must be recognized that it may not always be possible to achieve total
compliance with water quality standards.
Region I asked each discharger to prepare a facilities plan that assessed a range of
alternatives that would result in complete elimination of discharges or compliance with water
quality standards. This requirement elicited the most heated discussions with the States and
permittees. In effect, what the policy says is that a CSO community must examine all
alternatives, from hydraulic elimination of all overflows, to satellite treatment, to the so-called
"no action" alternative. They should develop a matrix arraying the economic, environmental,
technical, and institutional costs and benefits of each alternative. Region I suggests developing
alternatives with flexibility, so that a creative mix of options can be used to reach maximum
protection in the critical resource areas. The preferred alternative will be selected through
agency review coupled with public participation.
If a proponent projects that a water quality criterion or water use will be impaired even
after all proposed controls are implemented, the proponent must show that attaining the
designated use is not possible because controlling the discharge would result in "substantial and
widespread economic and social impact." (It would be too costly to fix.) In the simplest terms,
a community has two choices. It can select an alternative that fully complies with its State's
current water quality standards, or it can request that the State adjust the standards downward.
These water quality standards redesignations will be granted only on a case-by-case,
water-segment-specific basis after the facts have been established and with the full spectrum of
public participation. It is important to emphasize that it is not the Region's intention to
encourage the States to change existing water quality standards classification to allow the
continued operation of CSOs. To the contrary, the Region supports the current water quality
standards and there is a difficult burden to be met if a revision to standards is to be sought.
However, since it may not always be practicable to construct CSO facilities to meet current
water quality standards due to the high costs, the Region's policy suggests an approach for
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addressing CSO discharges that is consistent with the law, regulations, and sound engineering
economics.
National CSO policy. When the National Strategy was adopted in 1988, it did not negate any
aspect of Region I's policy. However, one provision that the Region may ask headquarters to
reevaluate is the provision that all flows reaching the POTW must meet secondary treatment
regulations. Region I has several situations where a POTW has more hydraulic capacity in
their primary systems than the secondary ones. Before the National Policy was adopted, mostly
all of the wet weather reaching the POTW received primary treatment as a minimum and
secondary treatment for the flow that could be handled by the secondary unit processes. The
combined flows, however, would not meet the NPDES maximum weekly effluent limitations.
Because of the National Policy, the POTWs have no option now but to reduce wet
weather flows or else violate their permits. Region I is encouraging POTWs to treat the
overflows where they occur, but this action may take years to come about.
Massachusetts Water Resources Authority's approach. Region I recently received the
Massachusetts Water Resources Authority (MWRA) Facility Plan for the cleanup of Boston
Harbor. It is an example of how complex and costly CSO treatment can be.
Boston Harbor encompasses 50 square miles with many swimming beaches and salt water
X
marshes and 1,200 acres of shellfish beds. It also serves commercial interests with oil tanker
and cargo transport. The area is presently treated with two primary WWTPs, which have gone
into disrepair. They will be replaced with one treatment plant (on Deer Island), which will be
one of the largest WWTP in the United States, with a capacity to treat 1.2 BGD. It will use
"stacked clarifier" technology, widely used in Japan, but not yet in this country.
The population affected by the CSOs is 300,000 (total population served in Boston
Harbor is 2.5 million). The CSO area consists of 12,500 acres with 400 miles of combined
sewers. About 5,000 industries are connected to the system. There are 87 points of overflow
in the service area and 10 billion gallons per year that flow directly into the Harbor. Beaches
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are closed one-third of the time. Shellfish beds are closed one-half of the time, and for those
that are opened, shellfish that are commercially harvested must be depurated at a State-
approved facility.
The MWRA has recently updated their CSO plan. In the plan, about 5 billion gallons
of CSO wastewater will be sent directly to the Deer Island WWTP. Of the remaining 5 billion
gallons per year that will need treatment, about 95 percent will be first captured and stored,
and then pumped to Deer Island. Figures 18 and 19 are diagrams of typical near surface
storage and storage tunnel systems. The system will capture 5 million gallons per year and is
estimated to remove 85 to 95 percent BOD, TSS, and fecal coliforms. The system will contain
a 300-foot deep shaft and 16 miles of 25-foot diameter tunnels below the Harbor. One of the
existing primary WWTPs will be replaced with a pumping station and a 12-foot diameter tunnel,
with outfall flowing through a 24-foot diameter tunnel. After treatment at Deer Island,
secondary effluent will be pumped and discharged 9.5 miles out into Massachusetts Bay. The
system will cost about $1.2 billion with limited Federal assistance.
For more information about the CSO policy, contact Richard Kotelly (see Appendix A).
To obtain a copy of MWRA's plan, contact MWRA, 100 First Ave., Boston, MA 02109.
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Combiied Sewer
Overflow Conduit
svSotf'1 I
Wel Weather
Overflew
Figure 18. Typical CSO Near-Surface Storage System
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OS
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p
O
c t- ^ "JeT e e
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COMBINED SEWER OVERFLOW PLAN FOR EAST LANSING, MICHIGAN
Charles Pycha, EPA Region V, Water Management Division
Chicago, Illinois
Many communities find it difficult to control combined sewer overflows (CSOs) because
of the large costs associated with separating stormwater from municipal sewer systems or
providing conveyance, storage, and treatment for CSOs. EPA Region V contains over 500
communities with combined sewers. To help them deal with typical CSO problems, in 1986, the
Region developed an official CSO policy and published a Technical Guidance Document for the
Development of a Combined Sewer Operational Plan (CSOP). The primary objectives of a
CSOP are to determine the status of an existing CSO collection and treatment facility and
identify alternate ways to operate the facility to reduce the volume and occurrence of CSOs
with minimal costs.
Preparing a CSOP has two phases. In Phase 1, municipalities examine their existing
combined sewer system and determine potential capabilities to improve system operations, such
as providing additional treatment or constructing new facilities. Phase 2 involves implementing
the recommendations generated during Phase 1. A CSOP should either precede or be a
component of a wastewater facilities plan.
\
Region V requires all communities in its jurisdiction to prepare a CSOP. In the plans
that have thus far been submitted to EPA, many municipalities concluded that they do not need
to make major changes to their CSO systems or that they can not afford to implement the
necessary changes identified.
To provide a model for other municipalities on how to prepare a CSOP, EPA and the
City of East Lansing, Michigan, worked together to prepare the city's CSOP. The plan is
described in the document, Combined Sewer Operational Plan for East Lansing, Michigan. The
plan consists of five major elements, including an inventory of the physical characteristics,
limitations, and hydraulics of the combined sewers, interceptors, overflow structures, and
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treatment facilities; an examination of the permits, ordinances, and other administrative controls
implemented by system users; a review of maintenance practices; the development of a control
strategy; and a schedule for implementing the recommended actions. The hydraulics analysis,
rainfall analysis, modeling of system flow, and consideration of industrial inputs were four
specific areas of focus of the East Lansing CSOP.
In evaluating system hydraulics, storage capacities present in the different areas of the
city were identified and used to estimate total flow requirements for the system. The more
overflow that can be stored in any one area may mean that much less overflow will need to be
controlled in another area either through end-of-pipe treatment or treatment at the POTWs, or
that fewer supplemental storage basins will need to be built.
The rainfall analysis determined that with a minimal increase in capital or O&M costs,
the city could partially or completely control 65 to 70 percent of the overflow caused by storms
of up to about .5 inches of rainfall, an event that is exceeded only 12 times per year. In
addition to determining the amount of control that is needed to control average yearly rainfall,
the rainfall analysis also helped the city determine the degree of treatment that will be needed
to control peak rainfalls that are predicted to occur every 5 to 10 years.
Using computer models and accurate historical records, EPA and the city generated flow
diagrams of the existing CSO and treatment plant systems and collection capacities. They also
created diagrams of the major interceptors used that included the sizes of the sewer and pipe
interfaces. The diagrams were used to identify areas where there may be flow restrictions or
capacity problems.
Because industries contribute to the volume of CSO in East Lansing, the project team
evaluated industrial CSO storage capacity and the options for flow attenuation, the possibility of
eliminating the discharge of cooling water or nonprocess waters into combined sewers, and
interceptor and bypass capacities.
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The CSOP identified several actions that East Lansing could take to better use existing
facilities to reduce CSOs, including:
Administratively changing how the city deals with the users served by contract.
Alternating the use of CSO storage with the storage available at the treatment
plant to increase the amount of wet weather flow treated.
Diverting some CSO to an alternate interceptor, increasing the wet weather flow
that can be conveyed to receive treatment.
Providing dedicated control structures to allow for for in-line storage in major
combined sewer collectors that could store CSO during rainfall events.
Providing off-line storage in drainage basins where in-line storage does not exist.
Implementation of the plan is expected to take about 5 years. EPA and East Lansing
estimate that over two-thirds of the CSOs from the city's system can be reduced or eliminated
by the plan. Because much information is readily available today on CSO controls, EPA
expects that the CSOP will be less expensive to implement than it would have been 5 to 10
years ago.
The operational plan for East Lansing is particularly useful as an example because of
the extent of variations encountered in this combined sewer system. For copies of the CSO
documents or additional information on CSOPs, contact Charles Pycha (see Appendix A).
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CONSTRUCTED WETLANDS FOR
WASTEWATER MANAGEMENT
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OVERVIEW OF WETLANDS TREATMENT IN THE UNITED STATES
Robert Kadlec, University of Michigan
Ann Arbor, Michigan
About 450 types of wetlands systems exist for treating a variety of wastes, including
municipal wastes, mine water waste, stormwater, and various industrial wastewaters. Wetlands
treatment can take place in natural or constructed wetlands sites. Principal categories of
constructed wetlands systems include densely vegetated overland flows, underground systems,
pond and island systems, and channels with floating plants. The forested wetland is a natural
treatment system.
The largest existing wetlands treatment system is Iron Bridge (see p. 109), which
currently treats about 13 MOD. Columbia, Missouri, is designing a system to treat 19-1/2
MGD. Most wetlands systems could serve populations of up to 10,000. Single family systems
are being promoted in Louisiana.
Natural wetlands. One way in which natural wetlands differ from constructed wetlands is that
the original plant species found in natural wetlands are almost always replaced or modified
when extra water or nutrients are added to the system. The natural species sometimes do well
in spite of this replacement For example, in Drummond, Wisconsin (population 700 to 800),
instead of discharging lagoon water into a Qass A trout stream, the town pumps the water into
a spruce sphagnum bog. The water progresses through the upper layer of the peat, then to a
small stream, and finally to the trout stream. In this system, some original sedge was taken
over by jewel weed and impatiens, and the cattails replaced some spruce and other species.
New growth for larch, however, was greater in the wetlands than other natural areas.
Densely vegetated overland flow. Densely vegetated overland flow channels are much like
trickling filters. The main purpose of the vegetation in this system is to create sites for the
bacteria to live. These systems provide effective treatment, although the plants in the system
do not provide good habitat for other animal species.
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One example of an overland flow system is in Incline Village near Lake Tahoe, Nevada,
where wastewater is first treated by a conventional aeration/clarification treatment plant and is
then piped 20 miles to a wetlands complex that previously was a desert ecosystem. The system
is operated only during the winter months because during the summer, evaporative processes
and irrigation of ranch land dry up the system. The level of nitrate in the effluent that enters
the wetland is about 40 mg/L, while at the far cells in the system, the level is only 1 to 2 mg/L.
Another overland flow system is in Gustine, California. In addition to treating
municipal wastewater, the WWTP must also process significant quantities of waste from a dairy
plant. After treatment in lagoons, the water is distributed to a set of parallel constructed
wetland cells and then to collection devices. After treatment in the wetlands, the water is
chlorinated and discharged into the receiving stream.
The town of Listowel, Ontario, and the Ontario Ministry of the Environment in Canada
conducted a 4-year landmark project that investigated five parallel wetland systems and ran
extensive monitoring program. In essence, they created the first data base on constructed
wetlands. The facility was fully operational within 4 weeks, because they did an intensive
planting with the help of local school children. In one experiment, cattails were clipped to try
to remove nutrients by harvesting. About 10 percent of the phosphorus was removed by this
method, but due to problems with the harvesting equipment, this method was abandoned.
The Des Plains River is a typical muddy midwestern river located in northern Illinois.
During the summer, suspended solids rise to a level of about 150 mg/L and there is a
substantial nitrogen and phosphorous load from surrounding agricultural areas. In this system,
land that was previously a natural wetland area, an agricultural and Christmas tree farm, and
then a gravel pit was converted to a series of constructed wetlands. The water is pumped from
the river into 4 cells of the complex and then back into the river. The water quality improved
to a suspended solids level of about 10 mg/L.
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Underground systems. Another type of system is called underground, gravel bed, or rock bed
wetlands, or rock reed filters. The distinguishing feature of this system is that the water is
maintained underground. The wetland plants that grow in the substrate pump oxygen into the
water below ground, thus treating the wastewater. Typical vegetation for this system is reeds.
A lagoon system in Benton, Kentucky (population about 4,500), was modified by the
TVA to provide a gravel bed system. Perforation in the piping system allows the lagoon water
to seep through the rocks and then down to the wetlands cell. During the winter, the
vegetation usually dies and stops nutrient uptake, but because microorganisms provide much of
the treatment, system efficiency can slow down but does not stop completely.
Also, Weyerhauser Paper Company ran a gravel bed test facility in Columbus,
Mississippi. The wastewater treatment system discharges secondary water into the wetlands
system; the treated water is then cascaded for oxygenation and discharged to surface waters.
One of the problems with this type of system is that the water does not always enter the
wetlands beneath the gravel, although it will eventually flow down into it. System designers
tried a variety of planting schemes to correct the problem, but additional research on the
hydraulics of these systems is needed. Overall, the system provides effective treatment (60/60
BOD/TSS entering the system; 10/10 leaving the system).
Pond and island systems. A third wetlands treatment type is the pond and island system.
*\
These wetlands are not always designed solely for water treatment because the partially treated
water from these systems is used to maximize wildlife benefits. These wetlands contain some
open water and some vegetation to the extent that the "edge effect" is maximized for birds and
other animals.
A typical pond and island arrangement in southern Mississippi, provides habitat for
endangered species. Another pond and island treatment system in Northern California is a
marsh and wildlife sanctuary that treats secondary water. Several hundred thousand visitors per
year visit the facility to hike, walk their dogs, and jog. The layout of the system contains twists
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and curves, as opposed to the typical rectangular cells. A similar type of facility in Lakeland,
Florida, is about 1,150 acres with no public access allowed.
The AMOCO refinery in Mandan, North Dakota, built a pond and island wetland
complex for treating refinery wastewater instead of dumping it straight into the nearby river.
Conjecture was that if the system didn't improve water quality, it would at least provide habitat
for water fowl. The refinery also placed trout in the last pond of the system and won an award
from the National Wildlife Federation for this project.
Channels with floating plants. Channels with floating, emergent plants are a fourth category
of constructed wetlands. Water hyacinths and duck weeds are two common plants used in this
treatment system. An example of this type of system is the lemma lagoon.
Stormwater wetlands treatment. Many stormwater wetlands treatment systems, both
constructed and natural, are located along the eastern seaboard. In an Andover, Massachusetts,
system, runoff from a 7,000-car parking lot that surrounds a 7-acre computer manufacturing
facility is channelled into a wetlands complex that blends with the natural landscape. Another
system adapted a natural red maple swamp for stormwater treatment. The Orlando Urban
Wetland Project, located on property that used to be a dump, is now a park, planted and
constructed for stormwater detention and treatment.
\
Infiltration. A few systems infiltrate into the ground water, but most systems do not. Where
natural soils do not provide a seal, liners such as those made of compacted clay (bentonite) are
used. In most natural systems, the wetlands formed because there is a natural seal.
Seasonal operations. Although some systems in northern climates slow down or stop operating
during the winter months, some processes continue. This can occur because microbial action
continues and filtration, removal of suspended solids, and denitrification can proceed. Also, in
an average winter, a northern wetland may not freeze at all. The vegetation holds up the ice,
which in turn supports a blanket of snow that insulates the system from the extreme weather.
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For more information on wetlands treatment, contact Bob Kadlec (see Appendix A).
(Also see Appendix E for a list of EPA Alternative Technology projects and Appendix F for
the current status of Modification/Replacement (M/R) Grant candidates by state.)
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DESIGN OF CONSTRUCTED WETLANDS/
STATUS OF CONSTRUCTED WETLANDS IN MISSOURI
Robert Kadlec, University of Michigan, Ann Arbor, Michigan
Randy Clarkson, State of Missouri, Jefferson City, Missouri
ROBERT KADLEC - Design of Constructed Wetlands
Based on 10 years of experience, environmental engineers have defined several
parameters and fundamental ecological processes that must be considered when designing
constructed wetlands. The main objective of these factors is to create resilient systems that can
tolerate wide natural and manmade upsets and still meet water quality limitations.
Design considerations. One basic consideration in designing constructed wetlands systems is to
plan ample time for meeting the treatment objectives. Some early constructed wetlands treated
water with extremely high hydraulic loading rates, which did not work efficiently. These systems
gained a poor reputation as a result. Other major considerations are to accurately calculate the
required water depth and flow regime of the system to properly foster the growth of the
selected plant species and protect ground water.
Wetlands systems must also be easy to operate and maintain. Gates, which often
require a lot of maintenance, should be carefully designed so that they function well. Operators
*\
should be able to recognize potential problems in advance and be ready to handle unforeseen
circumstances such as dike failures and the plugging of structures with detritus.
Natural factors. Another major design consideration is that constructed wetlands are subject to
strong environmental forces beyond human control. System operators must be able to manage
the flow of water under all probable and extreme hydrological and climatological scenarios. For
example, the rainfall and evaporative conditions in Michigan for the last few years have varied
dramatically. It rained 12 inches in September 1986, while it did not rain at all during the
summer of 1988. In 1986, there was 30 percent added flow, while in 1988 there was a -80
percent flow (80 percent of the water evaporated). For this reason, constructed wetlands might
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never operate at steady state conditions, and they may be difficult to evaluate from a regulatory
standpoint
Another ecological factor to consider is that plant growth in constructed wetlands can be
faster than in a natural setting because seedlings can take up considerable amounts of nitrogen,
phosphorous, and other constituents. The biological processes of system operations also can be
affected by the accumulation of detritus. Data collected from newly built systems may therefore
represent the building up of vegetative crops, whereas data for older systems may represent the
decomposition of dead plant matter as well as the wastewater.
Calculating design parameters. System designers have been successful using dyes to study
fundamental wetlands processes, such as surface flow and transition flow regimes. The standard
hydrological "Manning's equation" that describes water flow through vegetated channels does not
seem to apply to constructed wetlands, however, where there are dramatic changes in water
depths, although other empirical hydrological formulas have been found to be useful. Design
equations available for estimating water quality considerations (i.e., BOD) are included in an
EPA design manual and other references (see below).
Other standard water quality parameters that must be calculated for designing
constructed wetlands are temperature coefficients, where the decay constant decreases as the
temperature decreases. For estimating contact time, system designers must consider blockage of
flow due to clumps of vegetation and channelization factors.
Instead of presuming first-order kinetics, system designers can use a mechanistic
approach to describe predicted performance of a wetlands system. For doing so, design factors
such as the hydraulic loading rate and influent concentration would be entered into a computer
program to generate reasonable performance of a system. A third approach is to evaluate data
using graphical means, such as plotting average annual BOD for an existing system.
Case study. Columbia, Missouri, intends to upgrade its wastewater treatment by building a
wetlands system that treated wastewater before discharging it into the Missouri River. The
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important considerations in designing this system were space limitations, land acquisition and
ownership, preservation of a wildlife area, and flood protection. The project will cost about $17
million, which included several million dollars for treatment plant upgrades; $4-1/2 million for
earth moving activities (which often can be the most expensive part of a project); $1 million for
a pumping station; and $4 million for the connecting plumbing.
Reference sources. Even though constructed wetlands is an innovative technology, numerous
sources of information are available on designing these systems. EPA headquarters and
Regions IV and V, and the Tennessee Valley Authority (TVA) wrote several manuals and
proceedings documents. These sources contain thousands of references on wetlands and
wastewater, ecological effects, and over 50 specific systems. Some of the sources are difficult to
obtain, however; about 80 percent of the material is not available through standard "searchable"
literature.
Contact Bob Kadlec (see Appendix A) for more information about the design of
constructed wetlands and the sources of additional information.
HOWARD MARKUS and RANDY CLARKSON - Status of Constructed Wetlands in Missouri
-v The use of constructed wetlands for water quality improvements is growing rapidly in
the United States. They are low cost, low maintenance systems that are the appropriate choice
of water treatment in many settings. The Missouri Department of Natural Resources (MDNR)
has limited experience with constructed wetlands. There are two facilities in operation in the
State at the present time and several more are planned. For these efforts, the MDNR also
evaluated three other facilities in a neighboring State.
Wetlands process. Wetlands remove pollutants through a complex series of physical, chemical,
and biological processes, especially adsorption, precipitation, sedimentation, and bacterial
transformations. In wetlands, oxygen is transferred down to the roots and rhizomes in the
rhizosphere, which is the major zone of activity for the aerobic bacteria. The oxygen that leaks
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out of the plants is used by the bacteria during respiration. Important reactions are
nitrification, the oxidation of complex organics to CO^ and the transformation of reduced iron
to oxidized iron.
The two most common types of constructed wetlands are subsurface flow systems and
open water systems (see p. 93). As a very general rule, after primary treatment, subsurface
systems require a surface area of 20 acres for each MOD of effluent Surface water systems
require a slightly larger capacity, although each system must be designed individually.
Case studies. In Shelbyville, Missouri, the treatment system consists of primary and secondary
lagoon cells, followed by a 4-cell open water and submerged bed constructed wetlands system.
The wetlands area is about 0.4 acres and consists of duckweed, pennywort, cattail, and reed
canary grass. The system operates at approximately 90 percent of design capacity. About one
year after the system was started, operators dredged the sludge and drained the initial treatment
cells. This wetland has not operated consistently well. MDNR identified unusual loading to
the system, slow plant growth, or extreme cold weather in winter as potential causes of this
problem.
Bethel, Missouri, is presently a small unsewered community. The proposed system for
this town is a 0.75-acre primary lagoon cell, followed by a 0.83-acre open water marsh wetlands
cell. The design P.E. is 150. Despite budgetary constraints, planners are optimistic that the
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system will provide the needed effluent quality. One concern is the potential for mosquitos to
breed, as the site is adjacent to homes.
Philadelphia, Missouri, another small unsewered town, is building a 1.34-acre primary
lagoon cell followed by a 0.63-acre 3-cell open water wetlands system. The design P.E. is 270.
Sturgeon, Missouri, is a low income farming community. It currently has three
overloaded 1-cell lagoons. The proposed system contains a 2-cell lagoon (6.36 acres and 1.91
acres), a 3.2-acre overland flow system, and a 0.88-acre 4-cell constructed wetlands (2 open
water cells and 2 submerged flow cells). The pipe valving of this system will allow for
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maximum flexibility. For example, over 60 flow combinations will be available throughout the
system. The design P.E. is 1,272.
The Sturgeon project is funded by the town and through grants. Officials are trying to
obtain additional funding for the University of Missouri to conduct research, collect significant
amounts of data, and demonstrate system performance.
Columbia, Missouri, currently operates a mechanical plant that discharges to Perche
Creek. The proposed system consists of a hydraulic expansion of the mechanical plant and the
addition of 4 open water constructed wetland plots totalling 135 acres. The design P.E. is
137,000.
One major consideration in building this facility is the flooding conditions of Perche
Creek and potential damage that can occur to the constructed wetlands due to high currents of
natural floods.
For more information about constructed wetlands in Missouri, contact Howard Markus
or Randy Clarkson (see Appendix A).
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OPERATIONAL PERFORMANCE OF REEDY CREEK
WETLANDS TREATMENT SYSTEM AND OTHER
SOUTHERN WETLANDS
Robert L. Knight, CH2M Hill
Gainsville, Florida
In the southern coastal plain states, wetlands make up a significant percentage of the
landscape. Florida has 11 million acres of natural wetlands, which cover nearly 30 percent of
the State. These natural wetlands, as well as constructed wetlands, play an important role in
the environmentally safe management and treatment of domestic wastewaters.
Overview of Florida wetlands treatment systems. Much of the original research on the water
quality treatment potential of wetlands is taking place in Florida. The State currently has 12
permitted active wetlands treatment systems including 2 constructed wetlands, 9 natural
wetlands, and 1 hybrid system.
The central Florida area contains examples of both constructed and natural wetlands
treatment systems. This presentation will contrast five different operational systems and focus
on the performance of the Reedy Creek system, which has the longest monitoring record of the
wetland systems in Florida. The main goal of this comparison is to demonstrate which
treatment processes are effective and which approaches may not be appropriate for wetlands
treatment. Table 13 is a summary of these five central Florida Wetlands Treatment Systems.
Poinciana Boot Wetland. The Poinciana Boot system was built in 1985 as a cypress dome
treatment system. It has the lowest flow of any of the central Florida wetlands, currently
permitted for 0.35 MGD with a proposed expansion to 0.85 MGD. After 5 years of operation,
the Boot system continues to consistently remove total nitrogen and total phosphorus. These
removals are partially the result of a long hydraulic residence time.
Orange County Eastern Service Area. The Orange County Eastern Service Area is a hybrid
system that combines overland flow, constructed wetlands, and natural wetlands components.
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TABLE 13
CENTRAL FLORIDA WETLANDS
TREATMENT SYSTEMS SUMMARY
g
Average Concentration (mg/L)
System
Name
Boot Wetland
Eastern Service Area
Lakeland
Iron Bridge
Reedy Creek WTS1
Reedy Creek WTS2
Area
(AC.)
115
220
1,230
1,220
85
88
Start
Date
1985
1988
1987
1987
1978
1988
Average
Flow
(MGD)
0.32
0.70
8.0
12.0
3.1
3.1
BOD5
In
3.5
1.5
3.0
6.0
5.8
2.5
Out
3.8
1.3
2.5
2.6
1.8
6.1
TN
In
7.1
3.4
7.0
4.8
8.0
6.0
Out
2.6
1.7
2.0
0.9
1.8
5.3
TP
In
3.7
0.5
9.3
0.6
1.4
0.5
Out
1.1
0.05
4.3
0.08
1.7
0.5
Permit
Limits
(mg/L)
TN TP
2.2 0.2
4.0 _
2.3 0.2
2.0 0.50
2.0 0.50
-------
Row into this system has been relatively low during its first 2 years of operation (1988 through
1989), and nutrient removals have been excellent. Suspended solids increase significantly in the
system.
Lakeland Constructed Wetlands. The Lakeland system was built in an abandoned phosphate
mining area and has been operating since 1987. An excellent network of monitoring stations
and a high level of interest by the operations personnel have resulted in the collection of some
useful information in a relatively short time for evaluating system performance. Phosphorus
levels are high in this system due to high influent concentrations and existing sediment
phosphorus load. Nitrogen removal has been excellent and clearly illustrates the dependence of
nitrogen removal efficiency on influent nitrogen concentrations. Nitrogen removal efficiency is
typically over 70 percent at inflow nitrogen concentrations above 8 mg/L, and declines to zero
at a nitrogen inflow concentration of about 2 mg/L.
Iron Bridge Constructed Wetlands. As with the Lakeland Wetlands, the Iron Bridge
Constructed Wetlands Treatment System (see p. 109) provides a high level of habitat value in
addition to its value for final effluent polishing. This habitat value results from a diversity of
wetland and open-water aquatic areas as well as the nutritive value of the highly treated
influent wastewater. Treatment performance at the Iron Bridge system to date also has been
excellent; however, the very low effluent goal for phosphorus may present problems in the
future.
X
Reedy Creek Wetlands. At Reedy Creek, one treatment area (WTS1) has been in operation
since 1978 at higher hydraulic loading rates (HLR) than any other permitted system in the
country. Monthly average flows have varied from about 1.5 to 6.0 MGD for a HLR range of 4
to 18 inches per week. A very healthy wetland ecosystem coexists with this HLR.
Influent water quality at Reedy Creek has varied significantly during the system's 13-year
operational history, although wetland outflow quality has been very stable. This system has
consistently reduced BODS and TN to less than 2.0 mg/L. Phosphorus removal does not occur
in this forested cypress wetland, apparently due to very low hydraulic residence times and
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phosphorus-saturated sediments. Table 14 is a performance summary of Reedy Creek's WTS1
from 1988 to 1989.
A second wetland (WTS2) was modeled after the success of WTS1. This system was
brought online in June 1988. Increases of BOD5, TN, and TP occurred as water moved
through WTS2. This resulted from solubilization of minerals left from peat oxidation in this
system after it was drained in 1969. While these outflow concentrations were declining over
time, this flushing effect was too gradual to allow continued operation without some other
treatment of these constituents prior to final discharge to Reedy Creek. WTS2 was abandoned
in September 1989. A performance summary of WTS2 is shown in Table 15.
Summary. Florida continues to be a major proving ground for the use of natural and
constructed wetlands for water quality management. Florida's innovative Wastewater to
Wetlands Rule provides biological criteria for assessing the success of these projects and may
serve as an example for other areas. Biological criteria such as allowable changes in plant
importance values, macroinvertebrate diversity, fish populations, and populations of threatened
or endangered species provide a more meaningful indication of environmental protection in
wetlands than traditional water quality criteria such as dissolved oxygen. Also, Florida's
Wetlands Rule recognizes the important treatment role of wetlands receiving wastewaters and
permits this treatment to occur in State waters as long as the biological criteria are met.
Reariewers of permit applications for new wetland discharges should be cognizant of the natural
factors at work in these systems and of realistic performance expectations. Research in
Florida's wetlands has contributed greatly to our understanding of these factors and how they
contribute to final effluent water quality. Wetlands treatment system permit language should be
flexible to allow for successful operation of these large, natural systems.
For more detailed information about the performance of each wetland system, contact
Robert Knight (see Appendix A).
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TABLE 14
REEDY CREEK NATURAL WETLANDS TREATMENT
SYSTEM NO. 1
PERFORMANCE SUMMARY8
Year
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
»\
1989
In
7.3
10.4
10.8
4.2
7.3
10.0
3.1
2.5
3.5
5.6
3.0
2.0
BOD5
Out
1.4
1.5
1.5
1.7
1.3
1.3
2.0
1.8
2.0
3.7
1.4
2.5
RR
1.1
1.6
2.2
0.9
1.2
3.4
0.4
0.3
0.7
0.8
0.4
-0.2
In
8.9
10.3
9.8
8.5
8.8
6.2
5.0
5.4
7.3
12.8
6.2
7.1
TN
Out
0.8
1.6
1.0
0.8
1.2
1.1
1.1
1.2
2.1
7.2
1.6
2.1
RR
1.4
1.5
2.1
2.1
1.9
2.0
1.6
1.7
2.6
2.3
1.2
2.2
In
1.4
2.5
2.7
2.4
2.4
0.7
0.6
0.5
0.6
1.4
0.6
0.4
TP
Out
1.9
3.0
3.2
3.0
3.5
1.3
0.7
0.7
0.7
1.5
1.0
0.4
RR
-0.01
-0.53
-0.53
0.16
-0.32
-0.47
-0.07
-0.06
-0.05
-0.04
-0.01
0.00
* In = Inflow Concentration (mg/L)
Out = Outflow Concentration (mg/L)
RR = Mass Removal Rate (kg/ha/d)
Area = 35 ha (85 ac)
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TABLE 15
REEDY CREEK NATURAL WETLANDS
TREATMENT SYSTEM NO. 2'
PERFORMANCE SUMMARY
Concentration (mg/L)
BOD5 NO3-N TN TP
Period In Out In Out In Out In Out
Jun-Dec 2.6 6.8 3.0 0.04 5.2 5.7 0.46 0.77
1988
Jan-Sep 2.4 5.5 3.0 0.05 6.9 4.8 0.44 0.49
1989
3 Area = 88 Acres
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CONSTRUCTED WETLANDS AT IRON BRIDGE TREATMENT PLANT:
ORLANDO EASTERLY WETLANDS RECLAMATION PROJECT
JA. Jackson, P.E., Post, Buckley, Schuh & Jernigan, Inc.
Orlando, Florida
In 1987, the City of Orlando, Florida, constructed a 1,220-acre wetland to remove
additional nutrients from treated municipal wastewater from the Iron Bridge Regional Water
Pollution Control Facility (WPCF) prior to being discharged to the St. John's River. The city
deemed the additional level of advanced treatment necessary because of the sensitivity of the
rivers and lakes in Florida to even small increases in nutrient concentrations. The system has a
20 MGD design capacity.
The wetland was constructed on low-lying land that previously had been heavily ditched
and drained to provide cattle pasture. To maximize operational control, over 15 miles of
earthen berms were constructed on the site in a segmented design. Water passes between the
cells through pipes located in the berms. Control structures, made up of box culverts and
flashboards, are on the upstream end of each pipe. System designers took advantage of the
natural grading at the site, which is approximately 0.2 percent from the influent to the effluent
discharge structure.
To enhance the use of the area by wildlife, the Orlando wetland is a surface flow system
X
with four ecological communities ~ a wet prairie, a shallow mixed marsh, a hardwood swamp,
and a lake. Depths range from 1 foot in the hardwood swamp, to 1.5 feet in the shallow mixed
marsh, 3 feet in the wet prairie, and 30 feet in the lake. The substrate consists of mineral soil
with 2 to 15 percent organic matter, primarily from the former cattle ranching activities. The
wet prairie is planted with Typha spp. and Scirpus spp., the mixed marsh with about 30
indigenous herbaceous species, and the hardwood swamp with nearly 160,000 seedlings of a
variety of tree species, primarily Taxodium distichum.
The wetland began receiving flow from the Iron Bridge WPCF in July 1987. Initial flow
was 8 MGD, which was increased to 13 MGD in August 1988. System operators anticipate
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that flows will increase to the full 20 MOD capacity by 1991. At the design flow, the detention
time through the wetland is estimated to be about 30 days. Water leaving the constructed
wetland flows across an 'adjacent natural marsh to the St. John's River.
Monitoring results and discussion. System operators monitor the water quality of the wetland
using a series of sampling stations located throughout the system, from the influent to the
discharge structures. Data are obtained monthly from three consecutive daily grab samples
taken from each monitoring station, except the influent and effluent stations, which are sampled
daily. Annual average total nitrogen and total phosphorus concentrations for 1988 and 1989 are
summarized in Table 16. Maximum effluent concentrations permitted by State and Federal
regulatory agencies are 2.31 mg/L for total nitrogen and 0.20 mg/L for total phosphorus.
Both required effluent limits were achieved in 1988 and 1989 in the first portion of the
wet prairie, which represents 11 percent (130 acres) of the system. Over 78 percent of the
nitrogen removal occurred in this section of the system, whereas no other cell indicated
significant decreases in nitrogen concentration. The influent nitrogen concentration increased
by 32 percent in 1989, yet the system removed similar amounts of nitrogen during both years,
80 percent in 1988 and 83 percent in 1989.
In 1988 and 1989, over 98 percent of the phosphorus removal occurred in the first 11
percent of the system, which is a more significant percentage compared to the nitrogen data.
*\
Phosphorus removal was less significant in the remaining cells, and some cells indicated an
increase in phosphorus concentration. The overall percent removal of phosphorus through the
wetland system was 83 percent in 1988 and 89 percent in 1989.
Operation and design considerations. The ability of the Orlando wetland system to provide
greater than anticipated levels of treatment may be due to the operational ability to control and
manage system flows. System operators have been able to prevent adverse effects due to
extreme flushing events and short-term winter conditions by storing water in the various wetland
cells and gradually drawing the water down. The system was designed with 3 feet of freeboard
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TABLE 16
WETLANDS NUTRIENT CONCENTRATIONS
AT IRON BRIDGE WWTP, 1988 AND 1989
Nitrogen1
Monitoring
Station
Wet Prairie
(WP)1 (influent)
WPS
WP4,5
WP6
Mixed Marsh
(MM)8
Hardwood Swamp
(HS)10 (effluent)
1988
4.18
1.53
1.51
1.27
0.96
0.84
1989
5.52
1.92
1.74
1.59
1.22
0.92
Phosphorus1
1988
0.572
0.103
0.102
0.106
0.091
0.095
1989
0.72
0.08
0.15
0.07
0.05
0.076
Percent
Area
Up-
stream2
0
11
16
32
67
100
Detention
Time3
1988 1989
0 0
6 5
9 7
18 14
31 24
57 45
"-\
'Figures are mg/L.
2Percent upstream area equals percent of the wetland area upstream of the sample station.
3Detention time in days approximated based on volume.
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above the normal high water line, allowing an additional 58 days of storage capacity at design
flows.
Another beneficial operational feature is the ability to isolate individual cells from
receiving flows. This control mechanism allows for draining individual cells and oxidizing and
compacting the sediments. System operators can then reflood a cell and allow it to stabilize
before it is brought back on-line.
Conclusions and recommendations. The 2 years of operating data from the Orlando wetland
provides evidence that it is possible to achieve nutrient concentrations lower than those
normally attained by conventional advanced waste treatment processes. The system was well
within compliance of permitted effluent limits, although the limits are among the most stringent
imposed in Florida. Design features that allow for controlling water depths and isolating
portions of the system are important factors in providing consistent and reliable nutrient
removal. Orlando system designers recommend that other systems build in this operational
flexibility.
From the data presented, it appears that the system was underloaded. Since only 11
percent of the wetland is providing treatment at a level greater than anticipated, system
managers expect that the system will continue to meet permitted effluent limits as the flows
approach design conditions.
*\
For more information on the Iron Bridge constructed wetlands, contact J.A. Jackson
(see Appendix A).
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COMPLIANCE WITH PERMITS FOR NATURAL SYSTEMS
Robert Freeman, U.S. EPA, Region IV
Atlanta, Georgia
Treating wastewater though natural systems is an innovative technology that has proven
to be a viable wastewater treatment alternative for many small and large municipalities.
Because natural systems are much less predictable than standard wastewater treatment
technologies, municipalities have raised several unique issues concerning how EPA is developing
NPDES permits for these systems. EPA enforcement personnel are presently investigating how
to deal with these issues so that this promising technology can be encouraged at the same time
the waters are protected.
EPA Region IV is an 8-state primarily agricultural area with an agrarian-based economy.
The Region contains numerous constructed wetlands and overland flow systems that treat a
variety of wastes including wastes generated from milk, beef, and pork production; livestock
excrement; and municipal waste. Although constructed wetlands show much potential for
treating a greater amount of these wastes, the Region has faced some difficulties in issuing
permits for these systems.
Permitting problems. One of the major difficulties in permitting natural systems is determining
an adequate length of time for a start-up period and the date when compliance should begin.
Natural systems do not operate like activated sludge plants or oxidation ditches that are
functional as soon as they are put into operation. Constructed wetlands might take two or
three growing seasons to reach steady-state conditions and provide efficient treatment, and an
exact length of time is difficult to predict. Also, unforeseen circumstances can arise in natural
systems, such as the presence of soils with high organic content that can affect initial
performance when subject to innundation.
As the permitting process is currently structured, permittees must submit Discharge
Monitoring Reports (DMR) every month that state if the system is in compliance. Permittees
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must meet specific effluent and flow limits and monitor the system at predetermined intervals.
The permits often provide no flexibility in dealing with widely varying growing seasons, weather
conditions, plant growth rate, and other ecological and meteorological factors, but when
compliance limits are included in a permit, they are very difficult to change administratively.
A Walt Disney World constructed wetlands, Reedy Creek (see p. 103), is one example
of a system that must pay a fine of nearly $400,000 because of permit noncompliance. Instead
of being allowed to continue to work with the wetlands, Disney World must construct a land
treatment system to replace the wetland that is in noncompliance.
Recommendations. It is important for permit writers to be aware that natural systems are not
as predictable as other wastewater treatment technologies. EPA must work with the States,
municipalities, industries, engineers, and biologists to develop a sensible compliance approach
for natural wastewater treatment systems that considers the viability of each natural system to
meet its intended application.
If EPA permit writers can tolerate multi-year start-up periods, constructed wetlands can
be a viable option for many municipalities. If not, then another means of wastewater treatment
should be seriously considered. The permit writer also may request that a system conduct more
intensive planting so that the system is closer to being fully operational when it starts up. This
is a more costly option then allowing the plants to grow naturally to fill out the natural system,
*\
but may be an appropriate compromise. The facility and the enforcement agency also may
need to develop a reasonable compliance schedule.
Permit writers must ask what level of water quality can be achieved by a stringent versus
a more lenient approach. As natural systems attain steady-state conditions, they may result in
short-term adverse impacts on water quality, but the long-term benefits may be greater overall.
If EPA wants to continue to encourage the application of natural treatment systems, it must be
flexible in its approach to permitting these systems.
For more information on permitting Natural Systems, contact Robert Freeman (See
Appendix A).
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INVENTORY OF CONSTRUCTED WETLANDS SYSTEMS IN THE UNITED STATES
AND WPCF MANUAL OF PRACTICE ON NATURAL SYSTEMS
Sherwood Reed, Environmental Engineering Consultants
Norwich, Vermont
EPA's Risk Reduction Engineering Laboratory (RREL) is compiling an inventory of
wetlands systems in the United States that are being used to treat municipal wastewater. The
inventory contains information on system location and design parameters. This information will
be used to compare and assess the different systems in operation, focusing on the common
factors found throughout. The universe for this inventory is relatively small and only includes
constructed wetlands with emergent vegetation for treating wastewater.
About 300 questionnaires were sent to EPA Regional offices and State agencies. Data
for over 102 systems have been returned and logged into a computer data base that will be
used to summarize and analyze the data.
System types in operation. Of the systems for which data has been collected, two basic types
are presently in operation in about equal trequency-free-water surface and subsurface flow
systems. Although at least one wetlands system is located in each EPA Region, over 50 percent
of the systems are found in EPA Regions IV and VI. This may be due in part to the active
*\
encouragement of the Regional office staffs. (See Appendix E for a list of EPA's Alternative
Technology projects.)
In free-water surface wetlands systems, the water surface is exposed to emergent
vegetation. The system contains some type of substrate to support that vegetation and a liner
to protect the ground water. From an engineering perspective, the plants in this system are an
attached root substrate. The microbial life that provides the majority of the treatment attaches
to the plant surfaces, the detritus, and other materials in the water column.
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The plants in a free-water surface system transmit oxygen to their root zone for survival.
The primary oxygen used to treat the wastewater, however, is based on surface reaeration. If
the plant canopy of a free-water system becomes too dense, the system may experience a very
low dissolved oxygen level at certain times of the year.
Subsurface flow wetlands are also called gravel bed wetlands, rock reed wetlands, and
other names. These systems have permeable media of up to 2 to 3 ft deep that support the
same emergent aquatic vegetation as the free water systems. These systems also contain a liner,
and a way to maintain the water level at a predetermined depth below the media surface.
Typical media are natural gravel or rock, but plastic media is also used. In subsurface flow
wetlands, significant treatment is provided by the plants, which pump oxygen into the effluent
being treated. If there is enough oxygen, the system will support nitrification and denitrification
as well.
Hydraulic loading rates. Preliminary findings show that most hydraulic loading rates are
expressed in terms of gallons per acre per day, or number of acres per MGD of system
capacity. Other important parameters, particularly for subsurface flow systems are surface area
loading and cross-sectional loading rates. In subsurface flow systems, accurately calculating
these parameters will help optimize the use of the gravel or rock surface.
^ Of the data thus far tabulated for the inventory, the mean value for the hydraulic
loading rate for free-water systems is about 8 acres per MGD. The loading rate for a system
designed for Columbia, Missouri, is about 5 to 6 acres per MGD. Earlier free-water surface
systems are larger by design then newer systems. As system designers began to recognize the
capabilities and limitations of these systems in terms of BOD and suspended solids removal,
they designed systems with less acreage.
The average capacity of subsurface or gravel bed systems is about 6 acres per MGD.
These systems can theoretically be smaller by design than free-water systems because the gravel
provides additional surface area for bacterial growth and wastewater treatment, similar to the
treatment provided by trickling filters or rotating biological contactors (RBC). As a result,
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reaction rates should be higher and performance should be better than with free-water systems
in equal periods of time.
Comparison of subsurface designs. There are two main approaches to designing subsurface
flow systems in terms of system configuration, preferred media, and optimal flow rates. One
design is configured in long narrow trenches layered with about 18 inches of 2- to 4-inch rock,
6 inches of pea gravel, and some kind of emergent plant at the interface of the pea gravel and
coarse rock. Detention time for this type of system is designed to be about 1/2 to 2 days.
Because these systems are not designed to oxidize ammonia, and are only concerned with
meeting BOD and suspended solid limits, the penetration of the root system into the full bed is
not extremely important; BOD and suspended solids can be removed in an anaerobic reaction.
The second type of subsurface flow system is designed to oxidize ammonia. This type of
system is configured with a wider entry zone bed and a smaller diameter stone, and the plants
are expected to eventually penetrate the full depth of the bed. The detention time is designed
to be 5 to 7 days. Several reports from operators of systems that have been on-line for several
years have indicated, however, that the roots of the plants have not yet penetrated below the
pea gravel coarse rock interface, but are spreading out at the interface instead. Because the
plants in these systems are the only source of oxygen, it seems that for these systems to
successfully nitrify, designers must either determine a way for the roots to penetrate or
economically provide an additional source of oxygen. If either of these measures is taken,
nitrogen should by effectively removed.
Comparison to lagoon system hydraulics. Both types of subsurface systems are experiencing
clogging and accumulation of detritus, perhaps due to hydraulic loading rates that are too high
(800 to 3,000 gallons per sq. ft per day) and bed configurations that are too long and narrow.
This conclusion can be made by comparing these systems to rock filters in wastewater treatment
lagoon systems built in the 1970s that are still operating today without clogging. These systems
were designed to strip algae from the lagoons to improve BOD using rock filters. They contain
very course rock (3- to 4-inch diameter) across the entire width of the lagoon cell. The
effluent of these systems must pass through the rock bed and then the collection pipe before
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being discharged,, which is a relatively small cross-section. Overall, the lagoons have a long wide
entry zone and a relatively short distance where the treatment take place. Hydraulic loading
rates are from 2 to 6 gallons per day per cu. ft. of rock, or 100 gallons per sq. ft. per day.
Rectangular or square beds may now be preferred over the long narrow cross-sections of
subsurface wetlands systems. As long as there is adequate entry and withdrawal distribution
piping, like that of lagoon systems, plug flow should not be a major concern and detention
times should be less than 2 days to meet BOD limits.
Other observations. In terms of removing algae, gravel bed systems seem to work more
effectively and consistently than free-water surface wetlands. Gravel systems also seem to work
better for smaller systems and can be located nearby to developments, schools, public places,
and the like because treatment occurs below the water surface and odors and mosquitoes do
not cause any major problems.
Water Pollution Control Federation (WPCF) Manual. Encouraged by EPA's Innovative/
Alternative program, the WPCF wrote a Manual of Practice (WPCFMOP) on Natural Systems.
The document took 2 years to complete and includes the input of many experts in this field,
including people from EPA Headquarters and the Regions and States. The manual contains
information on aquaculture, land treatment, lagoons, wetlands systems, large-scale onsite systems,
other technologies. To obtain a copy of this manual, contact the WPCF.
For information about the wetlands inventory, contact Woody Reed (see Appendix A).
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DISINFECTION
-------
ULTRAVIOLET DISINFECTION STUDIES AT REHOBOTH BEACH, DELAWARE
Karl Scheible, HydroQual, Inc.
Mahway, New Jersey
In July through August 1989, a large-scale field study was conducted at the Rehoboth
Beach Water Pollution Control Plant in Rehoboth Beach, Delaware, to investigate the
ultraviolet (UV) light disinfection process. The U.S. EPA (OMPC and RREL) and the City of
Rehoboth Beach sponsored the project. The study had several objectives. First, EPA wanted
to develop UV design information for Enterococcus and E. coll, which may be used to establish
permit requirements in lieu of fecal or total coliform. Second, the study would demonstrate the
UV process design protocol described by the EPA design manual, Municipal Wastewater
Disinfection. Third, the project would assess the capacity and sizing of the existing UV system
at Rehoboth Beach using the design model approach, and determine the corrective action
needed to bring the system into full compliance. The experimental design, data collection
program, and analysis of data were based on the format and protocols presented in the design
manual.
Facilities. The treatment plant operations (Figure 20) include screening, oxidation ditches,
secondary clarification, microsceening, UV disinfection, post aeration, and final discharge into
the Lewes Canal. The system is designed for BOD and nitrogen removal. It is constructed as
two parallel trains, both of which are utilized during the summer beach season, while only one
is needed during the "off-season." Sludge is aerobically digested and land applied.
The average design flow of the plant is 3.4 MGD. The design maximum daily flow is
5.1 MGD. The average BOD and TSS limits are 19 and 15 mg/L, respectively. Nitrogen
removal is required from April through September, with an average limit of 3 mg/L.
Disinfection limits are an average fecal coliform (col) density of 200 col/100 mL, and a total
coliform density not to exceed 1000 col/100 mL. The total coliform requirement is the limiting
factor when considering the capacity of the UV process.
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0,1
Conlrvl
Bu>Min«
Poll At'OliOn
M
^- Si*p gait a* tcrttn (
CtM*f Pitr
^ $ie» »on
N- 0«trlle>
Clo..l.t.t
MiC'OHfOKit'l
f ! Mtltf ln«
Slfutlur*
C*Ml
Figure 20. Schematic of the Rehoboth Beach, Delaware, Wastewater Treatment Plant
Operations
-120-
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The UV system is comprised of two bays, each capable of receiving the peak total plant
flow and each with two channels fitted with UV equipment. Each channel has six modules
placed in series and divided into three banks (two modules per bank). Each module contains
28 lamps sheathed in quartz sleeves, yielding a total of 168 lamps per channel and 336 lamps
per bay. The lamps are placed vertically into the channel, with the flow direction perpendicular
to the lamp axis. The lamps have an effective arc length of 0.75 m. The liquid level is set by
a fixed downstream weir in each bay.
New UV equipment was installed in the second bay to accommodate the experimental
studies (see Figure 21). Four new vertical lamp modules were installed in the first channel,
differing from the existing vertical lamp modules by their lamp arrangement and by their head
loss. Each module contained 28 lamps and had the same UV density as the existing modules.
The four modules were operated as two banks in series. Horizontal lamps were installed in the
second channel, arranged as two banks in series. There were seven modules per bank, each
with four lamps. The direction of flow in this system was parallel to the axis of the lamps.
Process design. The study focused on generating data to calibrate the UV disinfection design
model (primarily set by the inactivation rate and the water quality characteristics of the plant
effluent), and verifying the calibration by comparing its predicted performance to that actually
observed over a range of operating conditions. The UV process design model estimates the
effluent density as a function of the wastewater quality (paniculate density, suspended solids,
UV transmittance, and initial density), reactor intensity, pathlength through the reactor, and the
hydraulic dispersion within the reactor.
The experimental protocol addressed specific data needs for the process design,
including direct testing for system hydraulic characteristics (dispersion), paniculate bacterial
density as a function of suspended solids, and the inactivation rate as a function of the average
reactor UV intensity. Reactor intensities were estimated by the point source summation
method as a function of the wastewater UV transmittance (at 253.7 nm). The study team used
wastewater data to estimate the design conditions for sizing and the calibrated design model to
estimate the lamp requirements for the plant at these design conditions. Performance data
-121-
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U I
Figure 21. Schematic of the Rehoboth Beach, Delaware, WWTP with
Ultraviolet Disinfection Equipment
-122-
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were collected over a range of operating conditions. The variables that could be controlled
were the flow rate and the number of banks in operation during a specific sampling. Each
sampling consisted of an influent and effluent sample, both of which were analyzed for total
and fecal coliforms, Enterococcus and E. coli. The influents were also analyzed for total
suspended solids and UV transmittance at 253.7 nm.
Wastewater characteristics. Overall, the quality of the Rehoboth Beach effluent was very high
during the term of the study. Table 17 summarizes average conditions for the plant. The flow
to the plant averaged 1.7 MOD, approximately one-half the design average flow. Because the
plant was operating at significantly less than capacity, the effluent may have been a higher
quality than what might have been produced if the plant approached design capacity.
Therefore, it may not be appropriate to test a UV system simply at its hydraulic design loadings
because possible undersizing problems may be masked by the wastewater quality. This points to
the utility of the analysis approach that calibrates the process equation, and then projects the
alternate water quality conditions that are reflective of design loadings.
Table 18 is a summary of the bacterial characteristics and degree of photorepair
observed at Rehoboth Beach. Particulate bacterial densities (not shown) estimated for
Rehoboth Beach were approximately one-third the levels previously shown for other plants and
reported in the Design Manual. Inactivation rates for total and fecal coliforms, Enterococcus
and E. coli, all were high relative to those estimated in a similar fashion at other plants. These
are summarized on Table 19. The rates for Enterococcus and E. coli both were somewhat
lower than observed for fecal coliforms. Table 20 summarizes the fecal coliform inactivation
rates of Rehoboth Beach and 6 other facilities. As shown, sensitivity to UV exposure is higher
at Rehoboth Beach. This, in turn, would result in a lower lamp requirement for equivalent
disinfection performance.
Process model calibration. After the study team defined the coefficients and system
characteristics, they calibrated the process model to the site application, and used the model to
develop design curves. To test the calibration, the team compared final effluent densities
predicted by the process equation to the effluent densities measured under specific operating
-123-
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TABLE 17
WASTEWATER CHARACTERISTICS AT REHOBOTH BEACH WWTP
July and August, 1989
(Beach Season)
Row (MGD)
Effluent
BOD5 (mg/L)
TSS (mg/L)
%T(T)
%T(F)
Total Coliform (100 mL'1)
Fecal Coliform (100 mL'1)
Enterococcus (100 mL'1)
E. coli (100 mL'1)
Average
1.74
5.2
6.1
69.8
71.7
182,400
28,200
1,140
3,600
95%
2.56
21.6
10.2
74.1 (10%
77.7 (10%
700,000
200,000
13,700
73,200
= 68%)
= 68%)
-124-
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TABLE 18
BACTERIAL CHARACTERISTICS AND
DEGREE OF PHOTOREPAIR AT REHOBOTH BEACH
July and August, 1989
Influent Effluent Photoreactivation
(Mean Ratio to FC) (Mean Ratio to FC) (Mean Log Increase)
Fecal Coliforms 1.0 1.0 1.56
Total Coliforms 6.5 5.4 1.96
Enterococcus 0.04 1.3 0
E- coli 0.13 0.7 0.84
-125-
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TABLE 19
BACTERIAL INACITVATION RATES ESTIMATED FOR REHOBOTH BEACH
Coefficients'
Total Coliforms
Fecal Coliforms
Enterococcus
E. Coli
a(x!05)
0.0037
0.0075
0.058
0.043
b
2.19
2.09
1.82
1.86
K at !>
3,000
1.52
1.39
1.23
1.26
6,000
6.95
5.91
4.36
4.58
"Inactivation Rate, K(second'') at Avg. Adj. Intensity, 1^ (uW/cm2).
-126-
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TABLE 20
COMPARISON OF REHOBOTH BEACH WWTP FECAL COLIFORM
INACTIVATION RATES WITH OTHER PLANTS
Fecal Coliform
Rehoboth Beach, DE
Bristol, CN
Newburgh, NY
New Windsor, NY
Suffern, NY
Monticello, NY
Port Richmond, NY
Coefficients'
a(xlO'5) b
0.0075 2.09
2.44 1.18
1.08 1.29
0.00061 2.2
0.004 1.92
0.69 1.4
1.45 1.3
Kat
3000
1.39
0.31
0.33
0.27
0.19
0.51
0.48
V
6000
5.91
0.70
0.81
1.23
0.72
1.34
1.18
K = almgb
"Inactivation Rate, K(second"1) at Avg. Adj. Intensity, Iavg (uW/cm2).
-127-
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conditions. The process model was shown to respond correctly to site conditions and was then
used to predict system performance at varying design conditions.
Summary. The following general observations were made, based on the results of the
Rehoboth Beach analysis.
Conventional UV systems effectively inactivate Enterococcus and E. coli; their
rates of inactivation were lower than observed for either total or fecal coliform.
System sizing on the basis of fecal coliform inactivation will be sufficient for
subsequent consideration for E. coli or Enterococcus.
Collection of relevant data at existing plants would benefit the assessment of any
changes in criteria. Data should include initial and final densities of the target
bacteria over an extended period of time.
When a new UV disinfection facility is being considered, piloting would be useful
for developing rate and performance data necessary for design sizing. If piloting
is not possible, it would be appropriate to use conservative estimates of the rate
coefficients and anticipated wastewater characteristics.
The process model approach is an effective way to size UV systems and evaluate
alternate configurations at projected design wastewater conditions.
For more details about this project, including the equations used, data collected, data
analysis, and a design example, contact Karl Scheible (see Appendix A).
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EPA REGION V SPECIAL EVALUATION PROJECT
OF CHLORINATION-DECHLORINATION
Charles Pycha, EPA Region V, Water Management Division
Chicago, Illinois
For several decades, municipal wastewater treatment plants (WWTP) have preferred
using chlorination to disinfect water and wastewater because this methodology is easy to use,
efficient, and less expensive than other technologies. Despite these advantages, disinfecting
water and wastewater through chlorination can result in several adverse environmental impacts
because toxic levels of total residual chlorine can be discharged into the receiving waters and
toxic halogenated organic compounds can be formed. Dechlorination is one of the alternatives
used to reduce the impacts and concerns associated with chlorine residuals.
Many wastewater treatment plant operators have expressed concerns about chlorination.
Other municipalities operate rudimentary systems or systems that do not operate properly. To
address these concerns, EPA is in the process of issuing a new policy on chlorination that
emphasizes the concern for aquatic toxicity due to the discharge of excessive levels of chlorine
into receiving waters. To provide additional guidance to utility operators and managers and
State personal, in March 1990, EPA Region V published a special evaluation report on
chlorination-dechlorination of municipal wastewater. The report examines various methods that
minimize the use of chlorine for disinfection, as well as the control systems available for
chlorination-dechlorination. Data for the report was assembled from the EPA Design Manual
on Municipal Wastewater Disinfection, a draft Municipal Wastewater Disinfection Policy
Development Document, various Water Pollution Control Federation (WPCF) Journal articles,
reports on improving chlorine disinfection efficiency and chlorine mitigation studies from the
Vermont Agency of Natural Resources and the Connecticut Department of Environmental
Protection, and information collected from Region V States.
Conclusions. The report includes several conclusions about chlorination-dechlorination. First,
the most practical and cost-effective solution for facilities that currently disinfect wastewater
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with chlorine appears to be optimizing the existing chlorination system, which will minimize the
amount of chlorine residual that reaches the waterways and aquatic life. Although optimization
procedures will vary from system to system, the principles are applicable to all WWTPs.
Another conclusion of the report is that the degree and efficiency of treatment that
precedes the chlorine disinfection process has a direct impact on the effectiveness of the
process. Effluent from a tertiary WWTP requires less chlorine than effluent from a secondary
WWTP. The same holds true for a well-operated secondary treatment plant, compared to a
similar facility operating with less efficiency. An exception to this occurs when low levels of
ammonia-nitrogen are present, forming monochloramine, which is a more potent disinfectant
than free chlorine. The interaction of the free chlorine and nitrified effluents is not totally
understood at this time.
A third conclusion of the report is that a well-designed chlorine disinfection process
includes rapid and thorough initial mixing to enable the more lethal free chlorine to work as a
disinfectant. A contact time of at least 30 minutes at peak flow in a plug flow contact chamber
that has a length to width (L/W) ratio of 70 to 1 maximizes the use of the applied chlorine
dose. Data collected over the course of a disinfection season will enable a WWTP operator to
correlate flows and residual amounts to required coliform limits and to add only the necessary
amount of chlorine to the system.
\
** The fourth conclusion is that applying automatic chlorine residual control increases the
opportunities for minimizing the use of chlorine. Automatic controls include simple flow
proportional controls, feedback residual controls, and compound loop controls.
The final conclusion is that plants must dechlorinate if they discharge chlorinated
wastewater into sensitive streams that require very low or zero chlorine residual permit limits to
be met. Sulfur dioxide is the commonly chosen agent to eliminate chlorine residuals.
Turbulent mixing at the point of sulfur dioxide application and a contact time of at least 60
seconds is usually adequate for residual control. Since no control system specific to sulfur
dioxide exists, the feed rate is controlled by measuring the chlorine residual. Two chlorine
-130-
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residual analyzers are often used, one to control the chlorine dosage and one to regulate the
sulfur dioxide dose rate. Continuous feedback control of chlorine residuals and on-line
monitoring to levels as low as 0.001 mg/L is now possible.
Recommendations. The report made several specific recommendations to wastewater treatment
facilities that chlorinate to minimize the impacts of chlorination on receiving waters and aquatic
life:
Ensure that the processes preceding chlorination are optimized to reduce the
organic and pathogenic load to the chlorination process.
Optimize the chlorination process by ensuring that rapid chlorination/wastewater
mixing takes place prior to when the wastewater is in the chlorine contact tank.
Make sure the chlorine contact tank has no short-circuiting or turbulence and
that the tank resembles a plug flow reactor.
Practice some form of chlorine feed rate control to prevent over- and under-
dosing. A properly sized feed rate control is necessary, and automatic flow
proportional control is recommended, as a minimum, to vary the chlorine dose in
relation to the wastewater flow rate. Also recommended is the use of feedback
residual and compound loop controls, which vary chlorine dose based on
wastewater flow rate and effluent chlorine residual, if economically feasible.
Chlorine feed rate controls and residual analyzers range in price from $1,000 to
$2,000, a cost that EPA feels is necessary and will save money in the long run.
Dechlorination facilities should follow the same recommendations for feed rate
control as chlorination systems.
The cost of implementing these recommendations and new controls, especially for plants
that must dechlorinate, can be offset in many cases by a short payback period.
Contact Charles Pycha (see Appendix A) to obtain a copy of this report.
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SMALL FLOWS CLEARINGHOUSE
-------
NATIONAL SMALL FLOWS CLEARINGHOUSE COMPUTER BULLETIN BOARD
Anish Jantrania, University of West Virginia
Morgantown, West Virginia
The National Small Flows Clearinghouse operates the Wastewater Treatment
Information Exchange (WTTE), a computer bulletin board system (BBS) that provides the
facility to exchange information on current research, news, available publications, and issues that
affect small community wastewater systems. The service is available free-of-charge nationwide,
24 hours per day. Some functions of the system include sending and receiving electronic mail;
advertising conferences; posting calendars of events and bulletins on environmental news;
accessing files on newsletter stories and research papers (without mailing diskettes); and
conducting surveys.
To access Wilt, the user needs a personal computer, a modem, and communications
software. The communications package must emulate an ASCII terminal with the following
setup:
Baud Rate: 1200 or 2400
Data Bits: 8
Parity: None
<*
Stop Bits: 1
BBS Number: l-(800)-544-1936
The logon procedure for WTIE is listed on Figure 22.
If you have questions about accessing the bulletin board, call the Clearinghouse voice
number at (800) 624-8301. Also refer to Appendix B for how to contact the National Small
Flows Clearinghouse Manager.
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ATDT 1-800-544-1936
CONNECT 1200
w w TTTTTTTTTTTTT
WWW T
W WWW T
W W W W T
W W W W T
W W W W T
W W T
mil
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I
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inn
EEEEEEEEE
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EEEEEEEEE
WELCOME
to the
Wastwater Treatment and Information Exchange Bulletin Board System
Press Any Key to continue
What is your FIRST name? /be
What is your LAST name? blow
Checking Users...
User not found
Are you 'JOE BLOW ([Y],N)? Y
What is your CITY and STATE? Orlando. FL
^
Welcome message
JOE BLOW from Orlando, FL
C)hange FIRST name/LAST name/CITY and STATE, Disconnect, [Rjegister? _r
Enter PASSWORD you'll use to logon again (dots echo)? password .
Re-Enter PASSWORD for Verification (dots echo)? password
Please REMEMBER your password
CAN YOUR TERMINAL DISPLAY LOWER CASE ([YJ/N)? y
UPPER CASE and lower
GRAPHICS for text files and menus
Change from N to N)one, A)scii-IBM, C)olor-IBM, H)elp ([ENTER] quits)? n
Text GRAPHICS: None
Figure 22. Log* On Procedures for the Wastewater Treatment Information Exchange (WTIE)
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Do you want COLORIZED prompts ([Y],N)7 n
Default Protocol
AJscii.Xjmodem.CJrcXmodem.YJmodem.NJone? n
Protocol: None
TurboKey: act on 1 char command without waiting for [ENTER]
Want TurboKeys (Y/[N])7 n
TurboKey Off
Small Flows Clearinghouse
- New User Questionnaire
Please enter your phone number
999-99-9999
Enter first affiliation (or private citizen if not a member of
any organization)
environmental consulting firm
Please enter your address below...
999 East Washington Street
Orlando. FL. 99999
Logging JOE BLOW
RBBS-PC CPC17.3 NODE 2, OPERATING AT 1200 BAUD,N,8,1
Bulletin Menu
1 - 01/02/90 Calendar of Events (February through December 1990)
7 - 01/24/90 WVU's demo project helps southern communities
8 - 01/26/90 MCLs for 38 organic and inorganic chemicals
Caller* f224 # active msgs: 99 Next msg #383
40 min left
MAIN MENU
PERSONAL MAIL SYSTEM COMMANDS UTILITIES
ELSEWHERE
E)nter a Message
K)ill a Message
R)ead Messages
S)can Messages
TJopic of Msgs
Bulletins
C)omment
l)initial Welcome
P)ersonal Mail
H)elp | F)iles Menu
J)oin Conference j Utilities Menu
X)Expert/Novice j G)oodbye
toggle |
MAIN command ?
Figure 22. (Continued)
-135-
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TOXICITY MANAGEMENT AT POTWS
-------
TECHNOLOGIES FOR TOXICITY REMOVAL AT POTWS
Perry W. Lankford, Eckenfelder Incorporated
Nashville, Tennessee
In general, there are three types of procedures for reducing toxicity from wastewater
treatment systems, regardless of the nature of the influent feed. The alternative approaches are
the causative agent approach, the source treatment approach, and the treatment approach.
The causative agent approach identifies and eliminates one (or more) chemical, which is
either the sole or predominant cause of the toxicity. This approach relies on conducting a
toxicity identification evaluation (TIE) to produce sound data on the chemical "culprits." If the
culprits identified by the TIE are not present in a form that can be eliminated, they must be
addressed through another approach.
The source treatment approach is where one or more source streams (as opposed to a
few compounds) is found to cause most of the problem. Although precise causative agents may
not be known, plant investigators can identify the segment of the collection system, plant, or
plants that may be causing the problem, and then treat the source. This approach appears to
be practical with at least a reasonable success rate. Experience suggests, however, that when
dealing with complex systems, large POTWs, industrial inputs, and sensitive aquatic organisms,
multiple sources, rather than a single chemical or source, are responsible for the toxicity.
«\
The treatment approach identifies weak areas in the treatment system and implements
improvements to the system to resolve the toxicity problems. In the majority of cases studied,
the treatment approach has been shown to be most effective.
Causative agent approach. An essential part of the causative agent approach is a fractionation
procedure, which involves making a series of decisions (see Figure 23) on what laboratory tests
to conduct, based on the extent of the toxicity and the results of tests conducted early in the
procedure. The goal of fractionation is to chemically eliminate a fraction of the contaminants
and thereby determine the amount of toxicity that is removed. This approach can identify the
-137-
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TOXIC
EFFLUENT
SAMPLE
SET ASIDE
'UNADJUSTED-
SAMPLE IF
APPLICABLE
SET TEMPERATURE;
CHECK pH, D.O.;
REMOVE LARGE
DEBRIS
SET ASIDE
SAMPLE FOR
PERSISTANCE
EVALUATIONS
ADJUST
pH AND D.O.
IF NECESSARY
ONE MICRON
FILTRATION
(MAY PRECEEO
OTHER STEPS IF
TSS HIGH)
TOXIC
souos
-ASSOCIATED
TOXICITY
ANION
EXCHANGE
CATION
EXCHANGE
EGION TOXICITY ATOXIC ^ /-/TOXIC)
i cr . No3 " i V_-_, s / ^~-, '
POSION TOXICITY _
( NH4* . Mg
ANION
EXCHANGE
SALINITY -(TOXIC)
TOXICITY V_____X
TOXICITY
MATCH LINE
(jroxicT)-*
AMMONIA,
CATIONS
OXIOANT HEAVY
TOXICITY METAL
(C«2,Br.D TOXiaTY
(Cd.Cu.Znl
AIR STRIP
pH 1
1
AIR STRIP
ORIGINAL pM
AIR STRIP
pH II
|
"%"£"
1
fH 3*
C II C it
TREATMENT, TREATMENT
ORIGINAL pH pH
|
1 MATCH LINE
Figure 23. Cuusutive Agent Approach Flow Diagi urn
-------
MATCH LINE
TOXIC V> ( TOXIC V-+ ( TOXIC V-4-
VOLATILE
ADDS
(H 2S, PHENOL)
VOLATILE
ORGANICS
VOLATILE
BASES
. ANILINB
VO
MORE TOXIC (POSSIBLE TDS
TOXICITY ADDED!
METALS
UK ELY.
I
MATCH LINE
(^Toxicf)+ (ATOXIC
READILY
SORBABLE
ORGANICS.
HQH M.W.
ORGANICS.
SOME METALS
SOPTWE
ORGANIC
ACIDS
SORPTIVE
NEUTRAL
ORGANICS
SORPTIVE
ORGANIC
BASES
GRADUATED pH TESTING
pH «
pH 7
pH t
ATOXIC ^ CTOXICO CTOXI(O
f
LESS MORE
TOXIC TOXIC
(AMMONIA) (METALS)
REFERENCE FOR LESS
pH 8 AND pH 8 TOXIC
TESTS, (METALS)
4-
MORE
TOXIC
(AMMONIA)
ALTERNATIVE PROCEDURES
CHEMICAL
OXIDATION
ATOXIC
OXIOIZABLE
ORGANICS
READILY
DEGRADABLE
ORGANICS
Figure 23. Causative Agent Approach Flow Diagram (continued)
-------
specific component that is toxic or a method to reduce the toxicity. However, the majority of
cases where the results of fractionation procedure tests lead to identifying a single contaminant
are in POTWs that have effluents with low to moderate toxicity. More often than not, the
results are ambiguous and identify several series of test procedures that can be conducted to
reduce the toxicity to simpler levels.
Source treatment approach. The source treatment approach identifies a greater number of
possible causes and solutions due to the broader nature of the approach (i.e., it deals with
source streams and not single chemicals). This approach is more cumbersome, however,
because the focus is not on the source of the toxicity per se before it reaches the treatment
system, but the toxicity that passes through the treatment system. For this approach,
investigators must follow a specific technique or series of analyses (see Figure 24) to identify
the toxic source or sources. To further screen out potential causative agents, provide definitive
answers, and identify treated samples that need further evaluation, biodegradability analyses
have been used. These analyses include BOD/chemical oxygen demand (COD) tests, glucose
inhibition tests, continuously fed batch reactor tests, biotreatability tests, and others.
Experience with character, toxicity, and screening tests has shown that successful source
treatment technologies can be applied to remove heavy metals, volatiles, organic chemicals, and
ammonia, as shown in Figure 25. Removal of heavy metals is well-established using metals
precipitation. Volatiles are rarely found to be a problem in POTWs because they are not very
toxic to aquatic organisms and are removed through standard procedures. Organics are,
therefore, the target of most toxicty reduction evaluation projects.
Organics removal technologies. One promising new technology to remove organics is peroxide
oxidation of source streams using ultraviolet (UV) disinfection light catalyses. Chemicals such
as tri- and tetrachloroethylene, 2-butanol chloroform, methyl ketones, carbon tetrachloride, and
tetrachloroethane have been effectively removed using this technique.
Researchers have also demonstrated ozonation to be an effective pretreatment for
removing many of the same organic chemicals, whereas anaerobic treatment can completely
-140-
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NO
STEP j
BIODEGRADABILITY
INHIOITION On
TOXICITY?
YES
STEP 2
SOURCE TREATMENT
REMOVAL OF IHIIIOITEn
OR TOXICANT?
I.E. METAL'S REMOVAL
STEP 5
SOURCE TREATMENT
IMPROVE
BIOOEGRADAOILITY?
I.E. CHEMICAL OXIDATION
AIR STRIPPING
STEP 8
SOURCE TREATMENT
REMOVE CONTAMINANTS?
I.E OXIDATION
ADSORPTION
STEP 3
BIODEGRADABILITY
ADEQUATE RATE
AND AMOUNT?
YES
STEP 4
EFFLUENT TOXICITY
ACUTE OR CHRONIC
TOXICITY?
NO
TOXIC
TOXIC
STEP 6
BIODEGRADABILITY
IMPROVED RATE
AND AMOUNT?
YES
NON-
TOXIC
DISCHARGE TO
EFFLUENT
TREATMENT SYSTEM
STEP 7
EFFLUENT TOXICITY
ACUTE OR CHRONIC
TOXICITY7
NON-TOXIC
NO
TOXIC
YES
STEP 9
EFFLUENT TOXICITY
ACUTE OR CHRONIC
TOXICITY?
NON-TOXIC
NO
RECOVERY. RECYCLE
SUBSTITUTION
OR ELIMINATION
Figure 24. Source Testing and Treatment Mow Diagram
-------
TO DISCHARC
RECYCLE
OR TREATMEF
FILTRATION
GRANULAR
CARBON
ADSORPTION
PRECIPITATION
ANAEROBIC
TREATMENT
OXIDATION
REDUCTION
PROCESS
WASTEWATER
HEAVY
METALS
WET AIR
OXIDATION
AIR OR STEAM
STRIPPING
CHEMICAL
OXIDATION
ORGANIC
CHEMICALS
VOLATILE
ORGANIC
AMMONIA
Figure 25. Soorce Treatment Technologies for Toridty Rednction
-142-
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degrade or chemically alter the chemicals. In complex systems, aerobic biological treatment is
the most often used end-of-pipe toxicity reduction treatment, which can be accomplished by
optimizing or upgrading the existing system.
Powdered Activated Carbon Treatment (PACT) is another end-of-pipe treatment used
more frequently today to enhance the performance of activated sludge systems and remove
organics. As shown in Figure 26, an increase in PAC results in a logarithmic decay of most of
the residual contaminants, including total organic carbon (TOC), metals, color, and toxic units.
Different carbon supplies have shown different results, some being up to 10 times more
effective than others. The significance of these differences is that carbons that can function
effectively at low dosages can be more readily used in systems where the WWTP is physically
limited.
Researchers have found solids retention time (SRT) or sludge age to be a principle
design criteria for biologically removing specific organics as opposed to organics in mass (like
TOC). In some instances, an adjustment of SRT alone can solve toxicity reduction issues.
Figure 27 shows the effect of SRT on reducing the toxicity of nonyl phenolics at one WWTP.
What occured at this site was that initially there was improved biodegradation, but toxicity
worsened as more BOD and TOC were removed. The investigators determined that as the
long chain nonyl phenolic surfactants biodegraded, which readily occurs, more toxic short chain
surfactants were created. The plant was, therefore, producing a more toxic effluent through the
^i
implementation of so-called improvements. Extending the SRT from the initial 4.5 days to
about 20 days eventually improved the removal of the nonyl phenolics and the toxicity problem.
This is an economically favorable solution.
When using granular activated carbon columns to remove TOC and other organics,
columns can reach exhaustion sooner if toxicity were the breakthrough parameter. Either
biological regeneration and/or substitution adsorption is the probable cause of this phenomenon.
Substitution adsorption is a speculative theory that assumes that higher molecular weight long
chain organics are more toxic and adsorptive, and shorter-chain materials that had previously
been adsorbed can be displaced by the longer chain materials. In one investigation, the
-143-
-------
ioor
80
o>
~ 60
O
O
a 4°
20
100
200 300
PAC Dosage (mg/l)
400
- 4,000
0.4
0.3
0.2
UJ
0.1
0
500
Figure 26. Contaminant Removal Trends in PACT Systems
-144-
-------
100
«
u
I
o
in
O
h»
00
SRT - 21 Days
50
SRT - 4.5 Days
Influent
1 2 3
Nonphenyl - Mono and Diethoxylate - mg/l
Figure 27. Effect of Solids Retention Time (SKT) on Toxicity Reduction for Nonyl
Phenolics
-------
breakthrough for toxic units did not occur until day 60 on the test columns, whereas the
breakthrough for TOC occurred by day 10.
Ammonia removal. The toxic form of ammonia is free ammonia, not total ammonia. The
amount of the total ammonia in the free form varies according to the pH and to a lesser
extent, temperature. At a pH of less than 7, ammonia levels below 100 mg/L would not be a
toxicity issue; this is the case in most POTWs. An ammonia level above 100 mg/L would be a
compliance problem for other reasons. At elevated pH levels (above 7.5), ammonia levels as
low as 20 mg/L can result in effluent toxicity. Nitrification is one of many established control
technologies available to deal with this problem.
For more information on toxicity reduction at POTWs, contact Perry Lankford (see
Appendix A).
-146-
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DEVELOPMENT OF COMPUTER-BASED MODEL AND DATA BASE
FOR PREDICTING THE FATE OF HAZARDOUS WASTE AT POTWS
John Bell, Enviromega Ltd.
Campbellville, Ontario, Canada
Environment Canada's Wastewater Technology Centre (WTC) is sponsoring a project to
develop a computer-based model and data base for predicting the fate of hazardous compounds
in wastewater treatment plants. A preliminary model is near completion and the data base will
soon be used to calibrate the model. The model is designed for microcomputer application
(IBM PC) and is user-friendly through the use of menus. It has the capability to simulate both
steady-state and dynamic systems and conduct sensitivity analyses. The model is designed to be
used by regulatory agencies as well as designers and operators of wastewater treatment plants.
The dynamic model allows the user to enter various kinds of input concentrations of a
compound or data on a spike or step input, and features built-in diurnal flow variations. The
built-in sensitivity analysis allows the user to vary one parameter, such as a compound's
biodegradation rate constant or Henry's Law Coefficient or a plant's recycle or flow rate, to
determine how plant performance might change as a function of the particular parameter. The
model also has one internal chemical data base, which a user can access but not change, and a
data base the user can change by inputting new data.
o
Unit processes and removal mechanisms. The model can simulate four unit processes,
including grit removal in aerated or nonaerated grit chambers; primary settling; aeration tanks,
which can be modeled as a series of 1 to 10 complete mix tanks; and secondary settling. The
four removal mechanisms modeled are volatilization (i.e., evaporation from the surface of
clarifiers), stripping (that occurs in aerated process vessels), sorption, and biodegradation.
The model takes into account the volatilization that takes place at air/water interfaces
and the prevailing conditions at these interfaces. Surface volatilization, from the surface of
tanks, is a function of the contaminant properties (i.e., Henry's Law Coefficient and diffusion
-147-
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coefficients), wind speed, and the tank surface area. Volatilization at clarifier weirs is a
function of the contaminant properties as well as the weir loading and dimensions.
The model allows input of subsurface or diffused aeration and surface aeration to
account for the two ways contaminants can be stripped in aerated process vessels. For diffused
aeration, the amount of stripping that takes place is a function of the contaminant properties,
oxygen transfer efficiency, and the airflow rate. For surface aeration, the stripping is a function
of the contaminant properties and the oxygen transfer rate. In the model, the oxygen transfer
rate is estimated from various input parameters, such as the aerator horsepower and the
standard oxygen transfer rates.
The model makes several assumptions about the sorption of contaminants onto primary
and activated sludge. The first assumption is that the sorption process is reversible; both
sorption and desorption can occur. Second, sorption and desorption are rapid processes
compared to the other processes taking place in the treatment plant. At every point in space
and time within the plant, equilibrium is established instantaneously. Third, the model assumes
a linear partition equation (i.e., absorption equilibrium can be characterized by a linear
partitioning equation that generally holds true at the low concentrations characteristic in
municipal treatment plants). The forth assumption is that the partition coefficient for primary
and activated sludge is the same when no experimental evidence to the contrary exists. When
no^xperimental partition coefficients exist, they can be obtained from the octanol/water
partition coefficient, available for many compounds of interest.
The model makes several assumptions for the biodegradation removal mechanism. The
model assumes a pseudo first-order kinetics for biodegradation, based on the low concentrations
of these contaminants normally found in municipal treatment plants. Also, the biomass
concentration in the system is assumed to be constant for both the dynamic and steady-state
model. (This condition would normally be present in the steady-state model.) The model also
assumes that the biodegradation rate coefficients are obtained from experiments because to
date, there is no reasonable way to obtain this information from theory.
-148-
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Pilot and bench scale tests. Model developers are conducting pilot plant and bench scale tests
to develop a data base of treatability parameters to be used to calibrate the model. Parameters
include biodegradation rate constants, sorption partition coefficients, and gas/liquid partition
coefficients (Henry's Law Coefficients).
One pilot test is taking place in Burlington, Ontario. The aeration tank for this test is
roughly 10 ft. high to simulate the depth of a full-scale plant. The pilot plant receives about 5
gallons per minute of influent (degritted raw sewage) from the local sewage treatment plant.
Another pilot study was conducted near Toronto. This plant received a larger input of
industrial waste and has higher concentrations of some of the compounds of interest.
Figure 28 is a graph of a dynamic experiment that estimated the biodegradation rate
constant and the sorption partition coefficient of an unacclimated system. In this case, 2-4-6-
trichlorophenol was spiked into the system at time zero and at 24 hours. Researchers cut off
the spike at 48 hours, after which time they observed the decay of the concentration in the
plant effluent. They used the data collected in conjunction with the model's nonlinear
regression routine to fit the treatability parameters to the data. As shown on Figure 28, the
model fit the observed data to the predicted data fairly well.
Similar tests were conducted with pentachlorophenol and for metals. Although in the
test for nickel, the model estimates for sorption closely fit the test data, results for cadmium
and other metals did not (see Figure 29). This might be because most of the metals are
removed by precipitation, and the model assumes they are removed through sorption onto the
solids. WTC is refining the model to handle more complex systems.
Figure 30 shows the experimental versus the observed results for steady-state pilot plant
tests on p-xylene stripping. These experiments were carried out under increasing air flow rates,
from Experiment #1 to #6. As shown on Figure 30, xylene is primarily removed by
biodegradation, but greater stripping occurs as air flow rate increases. The model predictions
were fairly close to the actual data.
-149-
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-osi-
Concentration (ug/L)
3
CD
en
o
o
"D
m
z
o
-------
CADMIUM
L/l
.8
D)
C
o
C
0)
o
C
o
o
.6
0
Predicted
0 Observed
_ Kp = 7.562
0
0
20
o
0
60
Figure 29.
40
Time (h)
Predicted Versus Observed Effluent Concentration for Cadmium
80
-------
191-
% STRIPPED
V.
n
s.
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V
ors
S3
X
2!
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-------
Preliminary full-scale tests of the model were carried out using data from three
petroleum refinery wastewater treatment plants (WWTP) and a POTW. Table 21 shows results
of the model tests that compared predicted and observed removal rates of several highly
degradable nonchlorinated aromatic compounds. As shown in Table 21, the model predicted
almost 100 percent removal, which matched actual test results. Other tests indicated that the
bench-scale and pilot plant data can provide adequate estimates of treatability parameters for
use in calibrating the model.
Steady-state tests were conducted at a WWTP near Toronto that has a fairly heavy
industrial waste load and receives many types of volatile organic compounds. Table 22 shows
the predicted versus observed results for stripping and biodegradation. The model predicts the
results of all compounds fairly well, except tetrachloroethylene, which shows somewhat reversed
results. Model developers are reevaluating the model's parameter estimations for
biodegradation and stripping and running additional tests on this compound. Dynamic tests
were also conducted at a WWTP, the results of which showed the close prediction by the
model.
In the future, the model will be refined to include sludge processing operations in
addition to the conventional activated sludge process, such as digestion, dewatering, incineration,
and final disposal. The WTC aims to make the model more flexible for handling different plant
designs and refine the biodegradation model to include different concentration ranges and
acclimation conditions. The data base also will be expanded to cover all the priority pollutants.
The WTC also would like to conduct comprehensive tests to field-verify the model, investigate
simpler parameter estimation techniques, and investigate the use of structure activity
relationships for developing biodegradation rate data.
For more information, contact John Bell (see Appendix A).
-153-
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TABLE 21
MODEL TEST: COMPARING PREDICTED AND OBSERVED REMOVAL FROM
THREE OIL REFINERY WASTEWATER TREATMENT PLANTS
Compound
Benzene
Toluene
Xylenes
Ethylbenzene
Benzene
Toluene
^ Xylenes
Ethylbenzene
Benzene
Toluene
Xylenes
0
Observed Predicted
Removal Removal
(%) (%)
Esso Refinery
> 99 99.7
> 98 99.7
> 99 99.5
> 98 99.7
Petro Canada Refinery
> 99.9 99.9
> 99.9 99.9
> 99.9 99.9
> 99.2 99.9
Montreal East Refinery
99.6 99.4
99.4 99.4
98.4 99.2
-154-
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TABLE 22
MODEL TEST: PREDICTED AND OBSERVED REMOVAL
FROM THE HIGHLAND CREEK WPCP
Compound
Dichloromethane
Chloroform
1,1,1 -Trichloroethylene
Trichloroethylene
Toluene
Tetrachloroethylene
p-Xylene
1 ,4-Dichlorobenzene
% Stripped
Predicted
3.5
3.6
5.3
7.6
0.4
8.9
0.9
17.0
Observed
2.6
7.4
10.5
10.7
1.2
58.7
1.3
19.1
% Biodegradation
Predicted
81.2
69.2
88.8
83.4
99.1
81.1
98.6
34.6
Observed
92.4
73.6
79.7
82.7
98.6
15.8
98.1
54.7
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PLANT PERFORMANCE EVALUATION
CROSS CREEK WASTEWATER TREATMENT PLANT
FAYETTEVILLE, NORTH CAROLINA
Bill Cosgrove, U.S. EPA, Region IV
Athens, Georgia
The Cross Creek Wastewater Treatment Plant (WWTP) is a 16 MOD (by design) pure
oxygen activated sludge plant operated by the Fayetteville Public Works Commission (PWC).
During November 1989, the U.S. EPA, Region IV, Environmental Services Division (ESD)
conducted a Plant Performance Evaluation (PPE) at the facility. Engineering Science, Inc. (ES)
of Fairfax, Virginia, requested the PPE to support a Toxicity Reduction Evaluation (TRE) the
company was conducting at the plant for EPA's Risk Reduction Engineering Laboratory
(RREL).
The objectives of the ES project were to evaluate selected TRE approaches and refine
the existing EPA protocol for planning and implementing TREs at municipal WWTPs. A major
objective of the EPA study was to demonstrate the PPE as a method within the TRE process
for identifying and correcting operational problems that may be influencing system performance
and effluent toxicity.
Toaicitv reduction evaluations. The EPA protocol for municipal WWTPs is contained in the
1988 EPA publication, Toxicity Reduction Evaluation Protocol for Municipal Wastewater
Treatment Plants (EPA 600/2-88/062). The objectives of a TRE are to evaluate the operation
and performance of a WWTP to identify and correct treatment deficiencies causing effluent
toxicity; identify the toxic compounds causing the toxicity; trace the toxicants to their source;
and evaluate and implement methods to control the toxicity.
Plant performance evaluations. A PPE is typically conducted as a first step in a TRE. The
objectives of the PPE conducted at Cross Creek were to collect design and operations
information to establish a data base for the PPE; review performance of the WWTP in
reducing conventional (BOD5, TSS, NH3, etc.) and nonconventional (organic compounds/metals)
-156-
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pollutants; evaluate hydraulic and organic loadings compared to design criteria; evaluate
characteristics of the sludge in the A/S system; review the operational strategies for solids
inventory, dissolved oxygen (DO), and return sludge control; and review the pretreatment
program and screening of septage/waste haulers.
Treatment facility process. The Cross Creek WWTP consisted of preliminary treatment, pure
oxygen-activated sludge, secondary clarification, and chlorination prior to discharging into the
Cape Fear River (see Figure 31). The plant was being modified to include an extended
aeration process (scheduled to be completed in 1991).
Waste activated sludge (WAS) was pumped to a gravity belt thickener, stabilized in two
aerobic digesters, and land applied. No supernant was being returned to the treatment process
from the aerobic digesters during the PPE; however, filtrate from the belt thickener was being
returned to the secondary clarifiers. About 25 percent of the total flow to the WWTP was
from industrial sources and included organic chemicals, meat rendering, metal finishing, animal
feeds, yarn dyeing, tire/rubber products, tank truck cleaning, electrical components, and fabric
bleaching/dyeing.
Process control testing and operational strategy. Process controls testing completed by the
operations staff included aeration basin DO; sludge settleability; MLSS/MLVSS; clarifier sludge
blanket depth; and waste thickened and digester sludge concentrations and settleability.
Operational parameters calculated included the sludge age based on mean cell residence time
(MCRT), food to microorganism ratio (F:M), and aerobic digester detention time.
The operational strategy included a target MCRT of 2.0 days for solids inventory
control; using an anoxic first stage in each pure oxygen train for nocardia control; maintaining
DO levels at the pure oxygen basin outlet of 6.0 mg/L with a 4.0 mg/L as a minimum;
maintaining a 3-ft sludge blanket depth in all 5 clarifiers; controlling the WAS flow rate based
on a series of settleability tests; and manually adjusting the chlorination rate to attain a residual
of 2 mg/L at the application point.
-157-
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Influent
Land Application
Aerobic Digesters
Secondary
Clari/iera
Splitter Box
No.3
^
Secondary CLarifiers
Belt Thickener
Poly
WAS
Sampling Locations
Screw Pumpj
o
Secondary
Clanfi«rs
Figure 31. Cross Crefck, North Carolina, \VWTP Flow Diagram
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Results. The average effluent BOD5 and TSS concentrations for October 1988 to November
1989 were 10 and 18 mg/L. The influent BOD5 and TSS concentrations averaged 150 and 188
mg/L, well below the design value of 250 mg/L. The plant had received high-strength industrial
slugs during the period. Influent pH values were extreme in April and June, 1989, at 9.0 and
4.9 S.U., respectively. Sampling did not indicate the regular presence of organic compounds in
the raw wastewater or final effluent.
Conventional parameters for the plant's performance for the EPA study, November 14
to 16, 1989, are listed in Table 23. The average effluent BOD5 and TSS concentrations were
within permit limits, and the average influent TSS concentration (58 mg/L) was low for an
industrial/domestic wastewater.
A continuous-reading pH meter installed for the EPA study showed several periods of
abrupt pH change on November 15, 1989 (0.5 to 1.5 S.U during the morning and 7.0 to 9.2
S.U in the evening). Severe pH excursions demonstrate the influence that industrial users can
have on raw wastewater characteristics of a WWTP and that slug loadings can influence plant
performance in terms of both pollutant removals and effluent toxicity. The Cross Creek staff
would normally not have discovered this slug loading, and would not have been able to comply
with EPA regulations requiring POTWs to assess the potential for interference and pass-
through, notify EPA and State authorities, and take appropriate measures to minimize the
impacts to the treatment works and the environment. The slug did not apparently upset the
<>
A/S system.
Table 24 lists the extractable and purgeable organic compounds, PCBs, pesticides, and
metals that were detected during the EPA study from samples collected at stations CI, CSE,
and C001 (see Figure 31). Twenty-one organic compounds and copper and zinc (of 31 metals
analyzed) were detected in the raw wastewater, all at levels well below those reported to have
an inhibitory effect on the A/S process. The final effluent had 9 of the original 21 organic
compounds above detection limits. The study detected seven different pesticides from samples
obtained from the first-stage aerobic digester, but no extractable or purgeable organic
compounds.
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TABLE 23
CONVENTIONAL PARAMETER RESULTS1
INFLUENT, SECONDARY EFFLUENT, AND FINAL EFFLUENT
Parameter
Row
PH
BOD5
SBOD5
TSS
COD
TKN
NH3
NO2-NO3
T-P
Alkalinity
OS/Grease
Cyanide
Suifide
Phenols
Units
MOD
SU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Influent (CI)
11/14-16/89
6.5-10.2
170
85
58
465
23
14
ND
5.6
170
80
ND
2.6
0.21
Secondary
Effluent (CSE)
11/14-16/89
NA
17
6
14
90
14
11
ND
3.4
135
72
ND
ND
0.0273
1 - Average of two composites (11/14-15 and 11/15-16) or grab samples,
station C001, a composite for 11/14-15 and a grab on 11/16.
2 - One sample collected.
3 - One sample below detection limits.
NA - Not analyzed.
ND - Analyzed for but not detected.
Effluent (C001)
11/14-16/89
15.1
7.2
17
10
14
90
12
11
ND
3.0
115
ND2
ND
ND
ND
or in the case of
-160-
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TABLE 24
ORGANIC COMPOUNDS AND METALS RESULTS
INFLUENT, SECONDARY EFFLUENT, AND FINAL EFFLUENT
Parameter1
Copper
Zinc
Purgeable Organic Compounds
Acetone
Methylene Chloride
Cis- 1 ,2-dichloroethene
Methyl Ethyl Ketone
Chloroform
1,1,1 -trichloroethane
Benzene
Trichloroethene
Toluene
Tetrachloroethene
Ethyl Benzene
(M &/or P) Xylene
O-xylene
Styrene
O-chlorotoluene
P-chlorotoluene
Extractable Organic Compounds
1 ,2,4-trichlorobenzene
Naphthalene
Bis (2 Ethyl/Hexel) Phthalate
Phenol
(3 &/OT 4) Methyl Phenol
PCBs/Pesticides
Aldrin
Diazinon
Gamma-BHC (Lindane)
1 - All units in ug/L.
2 - Estimated concentration.
3 - Detected in one sample
Influent Secondary Effluent
(Ci)
11/14-16/89
35
170
230
ND
2.92
25"
132-4
31
2.7"
1.2"
182
23
3.T2
19
12"
992
55
4.12
312
142
ND
10"
162
0.27
0.883
ND
and below detection
(CSE)
11/14-16/89
ND
33
ND
ND
0.73"
ND
5.5i4
102-4
ND
0.7"
0.83"
8.7
ND
ND
0.91"
ND
92,4
ND
5.42
ND
18
ND
ND
ND
0.522-4
0.0462
limits in the second
Final Effluent
(C001)
11/14-16/89
ND
31
ND
ND
0.67"
ND
5.6
4.8"
ND
ND
0.6"
8.7
ND
ND
ND
ND
8.6i4
ND
lli4
ND
ND
ND
ND
ND
0.65
0.062
sample.
4 - One of the two results is an estimated value.
ND - Analyzedxfor but not detected.
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Although the concentration of organic compounds and metals observed during the EPA
study did not indicate significant pollutant pass-through or toxicity to the A/S process, the
presence of numerous priority pollutants and the occurrence of a slug loading on November 15,
indicated a potential for A/S system upsets.
Acute toxicity tests showed that no significant mortality occurred in the fathead minnows
(Pimephales promelas) in either the secondary or final effluent. Significant mortality did occur
in the daphm'ds (Ceriodaphnia dubia) in all samples. Chlorine did not appear to play a role in
the cause of toxicity, as demonstrated by identical LC50s in the secondary and final effluent
samples. The pesticide, diazinon, was apparently related to the toxicity results at the final
effluent.
The EPA conducted unit process evaluations on the grit chambers, pure oxygen basins
and secondary clarifiers. Table 25 lists the operating parameters of the pure oxygen system,
based on data collected during the EPA study and average data for October 1988 to September
1989. The system was not hydraulically or organically overloaded during the study.
Recommendations. Several recommendations were made to the Cross Creek WWTP, reflecting
the conditions observed at the time of the EPA study:
The PWC must eliminate the receipt of slug loadings that can potentially upset
the A/S system, influence performance, and result in effluent toxicity. The PWC
should increase alarm system monitoring of influents and the frequency of
priority pollutant monitoring in raw wastewater.
The source of the pesticides detected in the raw influent and aerobic digester
should be identified, and the influence on pesticides on POTW performance and
effluent toxicity should be evaluated.
The DO levels in the pure oxygen system should be increased to the minimum
target concentration of 6.0 mg/L and the actual detention time in the pure
oxygen basins should be determined by dye dispersion testing.
The WWTP staff should monitor the delivery of septage to the plant.
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TABLE 25
PURE OXYGEN SYSTEM OPERATING PARAMETERS
EPA STUDY AND 10/88 to 8/89
Parameter
MLSS
MLVSS
Detention Time 1
2
Organic Loading
F:M3
MCRT
Surface Overflow Rate
Solids Loading
Units
mg/L
mg/L
hr
hr
Ib BODs/lOOO cu ft/d
d'1
d
gal/sq ft/day
Ib/sq ft/day
1 - Not including return activated sludge
2 - Including RAS flow (assume RAS 50
3 "* - Based on basin outlet MLVSS.
EPA Study
3,600
2,950
2.4
1.7
107
0.58
NC
460
21
(RAS) flow.
percent of plant
10/88 to 9/89 Design (22)
4,030 6-8,000
3,220
2.6 1-3
1.8
85 100-200
0.4 0.25-1.0
2.94 8-20
416 400-800
21 20-30
flow).
4 - Based on average for seven months.
NC - Not calculated.
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The Chief Operator should be provided with software that can quickly prepare
trend charts and basic statistical comparisons.
The oxygen uptake rate should be measured on a regular basis to establish a
baseline record of sludge activity.
For a more detailed report on the Cross Creek WWTP project, contact Bill Cosgrove
(see Appendix A).
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WASTEWATER TECHNOLOGIES FOR
SMALL COMMUNITIES
-------
EPA'S SMALL COMMUNITY STRATEGY
Ann Cole, U.S. EPA Regional Operations, State and Local Relations
Washington, D.C.
In the United States, there are 40,000 units of government below the State level. The
average local government serves between 1,000 to 2,000 people, for which it receives only about
$200,000 per year from all funding sources-Federal, State, and local. With these limited
resources, the town or municipality must fund its entire budget, including road and bridge
repairs, police and fire protection, libraries, landfills, sewerage, salaries, rents, mortgages,
insurance, contributions to trust funds, and compliance with local, State, and Federal
regulations. To address questions concerning the extent to which small communities can comply
with environmental regulations and to ensure that small municipalities build environmentally
healthy communities without being overly burdened, EPA established the Small Community
Coordinator (SCC) program.
The role of the SCC is two-pronged; one aspect deals with rule-making and the other is
outreach. To accomplish rule-making that will be tolerable by local communities, the SCC
program aims to improve the implementation of the Regulatory Flexibility Act of 1980 in
cooperation with the Office of Standards and Regulations. This act requires Federal agencies
to estimate the economic impacts of implementing a particular regulation on small communities
\
compared to the level of resources available for compliance, and suggest less expensive or
nontechnical compliance alternatives for the communities. To help conduct economic analyses
of small community regulations, the SCC program will develop a cross-media data base.
To ensure that a geographic perspective is represented in Agency policies, the SCC
promotes Regional office involvement in small community issues. To attain this goal, EPA has
assigned a representative from each program office and Region to work with the SCC to
represent the small community contacts nationwide and programwide. The SCC program plans
to identify gaps and overlaps among all the Agency's small community programs and coordinate
efforts to close the gaps.
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To accomplish greater outreach, the SCC program is coordinating cross-media
information exchange activities, because in a small community, the air, drinking water, and
wastewater coordinator might be the same person working with one limited budget to comply
with all environmental regulations. Helping EPA's cooperative management, technology
transfer, innovative financing, and technical assistance programs focus on and consider small
community issues and concerns is another goal of the SCC program.
The SCC cooperates with key external organizations to develop greater understanding of
small community environmental problems and the need for the SCC program, coordinate the
Agency's perspective on the localities, and establish a working relationship that will maximize
environmental results. These organizations include the National Advisory Council on
Environmental Policy and Technology (NACEPT) and the Environmental Financial Advisory
Board (EFAB).
Specific to wastewater treatment, one way the SCC will work with OMPC's SCORE
program (see p. 167) will be to discuss ways in which small communities can address the new
more stringent sludge regulations. It is likely that many small community local officials will
need assistance in figuring out viable alternatives for sludge disposal, if landfills are full or
regionalizing, land application is no longer allowed, or incineration causes unacceptable levels of
air pollution.
^
EPA's mission to protect human health and the environment applies to all of the
nation's citizens. Although small communities present a unique implementation arm of the law,
citizens of these jurisdictions must also have equal access to environmental protection.
For more information on EPA's Small Community Strategy, contact Ann Cole (see
Appendix A). Also see Appendix D for a list of EPA's Regional wastewater treatment
outreach coordinators.
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APPROPRIATE TECHNOLOGIES FOR SMALL COMMUNITIES
Randy Revetta, U.S. EPA., OMPC
Washington, D.C.
OMPC's Small Community Outreach and Education Program (SCORE) provides
technical and financial management information about wastewater treatment to nontechnical
decision-makers, such as small community local officials. In addition to distributing publications
and participating in conferences/workshops, SCORE works closely with other Federal agencies
and National Associations to leverage support to address the needs of small communities.
SCORE sponsors a limited number of national demonstration projects and supports the
establishment of State-level outreach programs by providing incentive grants through the
Regions to State programs and State-level assistance providers. In the past 3 years, SCORE
has distributed over about $450,000 in funding to States and other outreach providers.
As Federal funds decrease over the next few years, small communities will be forced to
finance entire costs of building conveyance and treatment facilities and thus will have to adopt
more affordable and appropriate technologies. They also will continue to look to EPA for help
in evaluating new and promising cost-effective technologies. To support this level of assistance,
a Small Communities Outreach and Technology (SCOT) initiative is being developed within the
SCORE program. Specifically, the SCOT initiative plans to integrate technology transfer efforts
with training assistance on wastewater and drinking water management and, possibly, solid waste
management.
At present, EPA's R&D laboratories in Cincinnati disseminate technology transfer
information to technical audiences, primarily through their Center for Environmental Research
Information (CERI). The SCOT initiative plans to broaden the delivery mechanism and
disseminate the information to a larger, less technical audience. Of course, this approach
assumes that the technical information will be revised and repackaged for a less technical
audience.
-167-
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The SCOT initiative will first focus on developing training materials based on
information on Innovative/Alternative (I/A) collection and treatment technologies that have
already proven to be reliable and appropriate for small community applications. The materials
should be based on performance data and design information already produced and distributed
as O&M and design manuals. The initiative also plans to develop training materials on sludge
disposal regulations, particularly O&M and septage disposal issues. These materials can be used
by State training centers and other national organizations or Federal agencies with grass roots
networks already in place to disseminate this information. A third area of focus for the SCOT
initiative is helping small communities deal with the potential impacts that regulations can have
on small communities.
Another proposed task for the SCOT initiative is to help small communities upgrade
existing treatment facilities by developing training materials on how small communities can
conduct environmental audits to evaluate and identify more effective and efficient ways of
meeting their wastewater requirements. This task can be accomplished by evaluating the most
common wastewater technologies presently employed by small communities and identifying low-
cost technological and operational modifications to these technologies.
For more information about the SCOT initiative or SCORE program, contact Randy
Revetta (see Appendix A). See Appendix E for a list of EPA Regional wastewater treatment
outreach coordinators.
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NEW DEVELOPMENTS FOR SMALL COMMUNITY SEWER SYSTEMS
Dick Otis, Owen Ayres and Associates, Madison, Wisconsin
Rich Naret, Cerrone & Associates, Inc., Wheeling, West Virginia
W.C. (Bill) Bowne, Bowne Associates, Eugene, Oregon
DICK OTIS - Small Diameter Gravity Sewers
Small diameter gravity sewers are a nonwater carriage system of wastewater collection.
They were first introduced in Australia as low-cost alternatives to failing septic tank systems, the
principle being to collect the drainage from the existing septic tanks for common treatment. In
the late 1970s, the technology was introduced in the United States, and today hundreds of these
systems have been installed across the country. Except for minor startup problems, the systems
have been operating well. Because of the success with initial applications, these systems will
likely see a greater number of applications in the near future.
Small diameter gravity sewers are typically used in low density developments where the
number of connections ranges from 200 to 500. In these systems, a septic tank located before
each connection removes suspended solids, trash, and grit that can cause obstructions. Small
diameter pipes, which are typically 4-inches in diameter, are used to collect the septic tank
effluent from the home, while the solids remain on site in the septic tanks. Periodically, the
solids are removed from the tanks.
-r»
Presently, the standard practice for designing small gravity sewers is evolving as
engineers learn potential applications and limitations of the technology. They have found that
initial design guidelines for the Australian systems have been very conservative. For example,
they have found that pipe-sizes smaller than 4 inches can be used successfully and that variable
gradients rather than uniform gradients are possible. Also, achieving minimum velocities of 1.5
feet per second (fps) during peak flow conditions is not necessary.
Concerns. The acceptance of these systems was tentative at first, because the small diameters
of the pipe led to concerns about hydraulic capacity and the ability of the system to handle
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peak and wet weather flows without creating backlogs or overflows. Another technical concern
was whether the small diameter lines would be subject to obstruction. To date, however, no
obstructions have occurred in any system. Whatever biomass has accumulated on the pipes has
turned anaerobic, sloughed off very easily, and has been carried on the floor of the pipes
without any problems.
Manhole covers have been sources of grit, detritus, trash, and other materials the sewers
are not designed to carry. To deal with this problem, cleanouts have replaced manholes with
spacings up to 1,000 feet apart. In 8 years of operation of these systems, none of the systems
has been cleaned or had problems with obstructions. Australian systems have been operating
for over 20 years without cleaning, but most of these systems have a uniform gradient with a
minimum flow velocity.
Designers of gravity sewers are finding that the systems need greater ventilation to
provide a free-flowing condition within the sewers. Odors can be a problem with increased
ventilation, however. To deal with odors, vacuum/air release valves are being installed on
cleanouts. These may be vented directly into the soil.
Odors can also be a problem at lift stations and anywhere there is turbulence in the
system. To prevent most odors from escaping, drop inlets have been installed at lift stations
below the low water mark. Elevated vents have also worked. Capping the top of the septic
-x*
tank inlet can eliminate the odors coming back from the sewers themselves into home stack
vents.
To deal with surge and peak flows, system engineers are trying to stabilize and maintain
a fairly uniform flow from each home. In many systems, the septic tank does a fairly good job
in attenuating flows, which rarely exceed .5 gallon per minute coming from the septic tank. If
flows are greater, they are usually for less than 15 minutes.
Surge storage devices have helped regulate flows where septic tanks do not, but these
tanks can create significant head loss of a few feet throughout the system, which would require
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the system to increase depth of excavation and associated installation costs. Insert screens
installed within the septic tank work well to reduce any head loss, and less leakage occurs when
the tanks are made of plastic or fiberglass. Check valves installed in some systems have
prevented the septic tanks from backing up into the home. To avoid corrosion, designers use
dry pit construction for lift stations.
System maintenance. Maintenance of gravity sewers is minimal. The most routine
maintenance is pumping the septic tanks, for which designers initially recommended a schedule
of once every 3 years. Because system operators have found that this schedule is far in excess
of what is needed, new estimates recommend pumping the tanks once every 7 to 10 years.
Some commercial connections will require pumping every 6 months to 1 year. Unskilled labor
can perform the maintenance work involved.
Costs. Costs of the systems vary widely from about $1,500 for equipment and installation per
home to $10,000 per home, depending on site specifics and client interests. Costs for
installation, equipment, service connectors, the main collector, and so forth range from $15 to
$80 per foot. These costs will probably decrease when the pipes are installed through trenching
rather than excavation, which is presently the most costly aspect of the system.
For more information on gravity sewers, contact Dick Otis (see Appendix A). Also see
Appendix E for a list of EPA's Innovative small diameter gravity sewer projects.
RICH NARET - Vacuum Sewer Technology
The areas best suited for vacuum sewer technology include sites with unstable soils, flat
lands, high water tables, rocky conditions, and generally low population densities. The
advantages of using vacuum sewers is that they use small pipe sizes, usually 3 to 8 inches, that
can be installed in very shallow depths. Unlike gravity sewers that have manholes at two fixed
points at a constant grade, vacuum sewer construction can go over, under, or around any
unforeseen obstacles, and contractors can easily make field changes as necessary. These
advantages result in lower construction costs. Operationally, the introduction of air into the
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vacuum sewers and the short detention time the sewage spends in the sump results in very few
odors. There are very few corrosion problems, as well.
The size of most vacuum systems is about 200 to 400 customers, with one vacuum
station, but systems range from less than 50 customers to 2,000 customers per station.
Experience has indicated that vacuum systems need 75 to 100 customers to make the
technology cost effective. Presently, about 40 to 50 systems are operating in the United States
in about 12 States. There are a few additional private installations and some small commercial
and industrial applications.
In the 1960s, four manufacturers were involved in introducing vacuum technology into
this country: Electrolux, Vacutec, Envirovac, and Airvac. The Airvac design predominates the
market today; about 90 percent of the systems use this equipment, and the few systems that are
not Airvac systems are being retrofit with Airvac valves.
As is normal for innovative technologies, the vacuum industry went through a series of
growing pains. Early problems were based on systems that had been installed without
sufficiently field testing the components. Operation and maintenance guidelines also were not
yet available. Additional problems occurred because designers and operators lacked a clear
understanding of the two-phased flow concept that forms the basis for this technology.
Fortunately, many of the early problems encountered have improved, although the literature is
not yet up to date with reporting the technological advances.
Cerrone & Associates has engineered six systems (with a total of nine vacuum stations
and 2,000 valves) in the United States, including design, planning, construction inspection, and
troubleshooting. The firm also is presently involved in the construction of another system, and
two or three more are scheduled to be built within the next 2 years. In addition, the company
has visited six other systems throughout the country to survey operating experiences. It
investigated systems that would provide a good cross-section of the technology, based on
topography, geographic location, size, and varying design concepts. The company also surveyed
an early system to find out if any improvements have been made.
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Although most of the systems surveyed experienced problems, most of the problems
occurred during the startup phase and were very short-lived. The problems occurred in six
general categories, including component defects (i.e., some of the small components of the
valves, small tubing, and controller parts were defective); design shortcomings (such as improper
selection of pump sizes and poor selection of discharge pumps); operator error; construction
mistakes (i.e., broken Gtting, poor compaction); equipment malfunction; and extraneous water
from the home user.
The first four categories account for 80 percent of the problems that occurred. These
problems can be avoided through improved design, tougher inspections, and hiring of more
skilled labor. Equipment malfunctions accounted for 5 percent of the problems that occurred.
This type of problem seems to be unavoidable because any mechanical equipment can
unexpectedly break down. The most devastating problem that has occurred to vacuum sewer
systems, accounting for 15 percent of the problems, related to extraneous water introduced into
the system by homeowners.
Despite these problems, the systems surveyed have all been providing reliable efficient
service due to significant improvements to key components. These improvements have reduced
the problems that plagued the early systems by 50 to 70 percent. As evidence of these
improvements, in a 1977 EPA technology transfer manual, the failure rate of vacuum systems
and the average time between service calls was 4 years, whereas in the systems surveyed in
1984, the average time between service calls was about 10 years. If designers, contractors, and
operators continue to learn about proper techniques, they can further reduce problems with
vacuum sewers.
The vacuum system industry has come a long way in the last 20 years. The early
reports of problems were not unfounded, but standardizing the industry, improving components
and designs, and more thoroughly understanding the technology, itself, has led designers to
make significant system improvements and create fewer problems. Vacuum sewers will most
likely provide a cost-effective reliable service to many small communities in the future.
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For more information on vacuum sewer technology, contact Rich Naret (see Appendix
A). Also see Appendix E for a list of EPA's Alternative vacuum sewer technology projects.
BILL BOWNE - Pressure Sewers
For an EPA project, Bowne surveyed several pressure sewer systems around the United
States with various equipment configurations.
A system in Pierce County, Washington, uses grinder pumps with built-in overflow
mechanisms used when the reserve space is filled. Most of the equipment is buried near to the
household. Any overflow that does occur drains into the existing tank and drain field. Each
pump is connected with a telemetry system so that high water alarm conditions are reported
directly to a computer located in the field office.
A system in Lake LBJ, Texas, uses 1,000 pumps with the grinder pump basin located
very close to the home. This means that the system has a short building sewer, a short
electrical service, and a nearby control panel, which eliminated the need for the electrical
junction box. The pump has a long cable that runs the wiring directly from the pump to the
panel. The extra amount of pump cable inside the grinder pump vault allows system operators
to lift out the pump easily without loosening any connections. Other systems in Texas use from
1,000 to 1,800 grinder pumps.
One major concern with the type of pressure sewer system used in Texas is the
potential for operators to receive electrical shocks. For example, to deal with a service call, the
operator must locate and dig up buried equipment. Because the systems use such small vaults
(about 2 feet in diameter and 4 to 5 feet deep), by the time the field personnel arrive, the
basin is full and overflowing. If maintenance personnel need to do electrical splicing, they are
in danger of getting shocked.
A system in Oregon is a septic tank effluent pump-type pressure system. The septic
tank and the pump vault extend down in the tank. The sludge settles to the bottom of the
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septic tank, and the system pumps only septic tank effluent, not sludge or scum. The liquid
level is held lower than in typical septic tanks so that a reserve space is available for dealing
with high waters. When an alarm sounds, the system has available storage of about 150 to 250
gallons.
A system in Palm Coast, Florida, is installed in the front yard very near to the property
line. If an adjacent home were to be built, the next tank would be installed adjacent to the
first one, so two 10-foot easements would combine to provide a 20-foot width for construction
and maintenance access.
One system in Missouri has been operating for about 15 years. It is a dry pit
installation with a 2-foot diameter pump vault that houses the pump and motor. The septic
tank effluent together with the sludge is pumped. This pump is self priming.
For more information on pressure sewer technology, contact Bill Bowne (see Appendix
A). See Appendix E for a list of EPA's Alternative pressure sewer technology projects.
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COMMUNITY MOUND SYSTEMS
Dick Otis, Owen Ayres and Associates
Madison, Wisconsin
Community mounds are a type of subsurface infiltration system for treating wastewater.
They are built above the natural ground surface in a bed of engineered sand fill material, with
the primary infiltrative surface constructed within the bed. A typical configuration contains a
pressurized wastewater distribution network within a gravel bed. The entire system is capped
with locally available fine-textured soil.
The largest community mound system in the United States has a capacity to treat about
20,000 gallons of wastewater per day (gpd), but the technology can be used to treat more than
30,000 gpd where costs become a limiting factor. The systems can have high capital costs, but
low operating costs, making them an attractive option for small communities. Unskilled labor
can operate these systems.
Community mound systems have faced many problems, and in 1986, EPA issued a
technical advisory to stop issuing construction grants for these systems. In 1984, Owen Ayres
and Associates conducted a survey of these systems and concluded that system designers and
evaluators had an incomplete understanding of how community mound systems function. If
properly sited, designed, constructed, and operated, community mound systems can provide an
excellent form of wastewater disposal.
One issue that remains a concern for managers and operators of small community
mound systems is ground-water protection. Nitrates from wastewater can leach from these
systems in levels that exceed drinking water standards. Strict standards protecting ground water
may continue to restrict the implementation of community mounds.
Siting, design, and construction. Designers of community mound systems must investigate site
topography, land use, geology, hydrogeology and soil texture, structure, and bulk density. They
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must determine the most effective way for the water to penetrate the soil, the most likely flow
pattern, and whether or not the system can achieve the desired level of treatment.
Siting remains the most significant cause of failures of this technology. Unlike
conventional wastewater treatment systems that can be built independent of the site
characteristics, community mounds must be built on well-drained sites with suitable soils for
wastewater percolation.
Community mound systems have two infiltrative surfaces. The primary infiltrative
surface is at the base of a gravel bed, where the raw wastewater actually infiltrates into the
sand fill material. The secondary infiltrative surface is the natural soil, which the wastewater
must infiltrate without creating a saturated condition that extends up into the sand fill. If the
sand fill becomes saturated, the "toe" of the mound most likely will leak. For optimal
treatment, most systems require at least 1 foot of sand fill and 1 foot of unsaturated natural soil
at all times below the primary infiltrative surface.
Systems designers typically either overestimate or underestimate ground-water mounding
conditions during mound operation. A number of analytical models can be used to estimate the
rise in the water table and investigate mound designs that will prevent encroachment of the
water table into the soil treatment zone. Although actual field experience does not correlate
well with the results of the models, the models help system engineers investigate a site and
evaluate a design more thoroughly.
Site evaluators can use soil borings to provide information on potential vertical water
movement, but borings do not always provide a clear picture of soil stratification. Small
stratifications within a boring can be missed. Backhoe pits that expose an undisturbed soil
profile are necessary to properly evaluate the soils for wastewater disposal.
To minimize the amount of land required for areas with slowly permeable soils, the
permeable topsoil must be left in place so that the topsoil can accept wastewater and move it
laterally as it slowly works into the subsoil. Mounds are also effective where a shallow water
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table exists due to slowly permeable subsoils or in areas with a shallow creviced or porous
bedrock. If the bedrock is not creviced or porous (such as in a granite impervious bedrock),
mounds will not function well because water will have no place to go.
Applying proper plowing methods during site preparation breaks up the organic layer
and creates a rough fill/natural soil interface. Contractors most often use chisel plows, plowing
along the site contours. Fill is placed over the plowed area with the tracked equipment,
keeping at least 8 to 12 feet of fill underneath the tracks of the equipment to prevent
compacting of the plowed soil surface.
Site criteria. Because recent experience has shown that mound systems are effective in treating
wastewater, some designers have begun to relax many site criteria. For example, when mounds
were first introduced, the minimum depth of the saturated zone from the original soil surface
was 24 inches. Research has shown that this can be reduced to 10 inches. Systems are
performing well at this depth. For vertical conductivity, earlier mounds were restricted to sites
where percolation rates were 120 minutes per inch. Today, the acceptable rate has increased to
300 (and in some cases 600) minutes per inch. Initial slope restrictions were 12 percent, but
now the criteria allows for steeper slopes. Systems now use retaining walls to support the
downslope of the mounds with steeper slopes.
FJU materials. Fill materials vary widely, and system designers must select them carefully. The
sand fill should have an effective size close to 0.3 mm and have a uniformity coefficient of less
than 7. Many systems use concrete sand. The ASTM Standard C-33 for fine aggregate is an
acceptable fill specification. If finer fill material is used, the design loading rates must be
reduced.
The design loading rate for earlier systems was 1.2 gallons per day per square foot for
the primary infiltrative surface area, but design criteria have changed somewhat in recent years.
For larger systems, the design flows are much closer to the actual flows, and it has been
necessary to reduce the design loading rates to more closely match actual operating infiltration
rates.
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The type of fill material used determines the most effective size for the gravel bed area.
Long and narrow infiltration beds are necessary to avoid organic clogging of the primary
infiltrative surface. It is difficult to diffuse oxygen underneath and through the center of a
square bed, and long and narrow beds help keep the underlying sand fill aerobic. Bed widths
are often 10 feet wide in smaller systems and up to 20 feet wide in larger systems.
Due to settling, the sand fill should not be deeper than about 3 feet under the gravel
bed on a sloping site. A 2 percent settling rate can tilt the bottom surface, overload the
downslope side, and create a breakout at that point. Beds within the mound can be tiered on
steeply sloping sites.
Wastewater distribution. Community mound systems must be able to distribute wastewater
within the mound as uniformly as possible. A pressurized network of pipes accomplishes this
task more effectively than a large diameter pipe. Multiple cells provide standby capacity to
allow for proper system management. Multiples of four cells are preferred, with each cell
designed to accommodate 50 percent of the flow, thus providing 100 percent standby capacity.
At a minimum, the cells should be rotated on an annual basis.
To obtain additional information on community mounds, contact Dick Otis (see
Appendix A).
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SEQUENCING BATCH REACTORS
James A. Heidman, U. S. Environmental Protection Agency
Cincinnati, Ohio
Sequencing batch reactors (SBRs) are variable volume wastewater treatment systems in
which the aeration, settle, and decant phases for each treatment cycle take place in a single
reactor. Consequently, SBR systems contain no dedicated secondary clarifiers or associated
return sludge facilities.
In 1989, EPA sponsored a study to investigate this technology. The study team visited 1
industrial and 20 municipal SBR facilities that had been operating at least 1 year and
telephoned 20 to 30 additional facilities for supplemental information. EPA is presently
analyzing the final data, so this discussion focuses on the different design approaches and
equipment that are being used.
Background. Many full-scale fill and draw systems were operated between 1914 and 1920, but
most were converted to continuous flow operations. The next attempt to use fill and draw
technology for municipal systems was the Pasveer ditch introduced in Denmark in 1962. This
approach used a modified oxidation ditch system with continuous inflow and intermittent settle
and discharge phases obtained by periodically turning off the aerator. In 1976, one facility in
Australia demonstrated a rectangular continuously fed intermittent discharge system, and since
that time, cyclic systems ranging in capacity from 18,000 gpd to 2 MOD have been used in that
country. The first modern SBR facility operated in the United States for municipal wastewater
treatment was a retrofit plant in Culver, Indiana, which went on-line in May 1980.
EPA last evaluated SBR technology in 1984. At that time, only four facilities were
known to be operating in this country and the Culver plant was the only facility that could
supply a significant body of operating data. Since then, over 150 SBR plants have been
designed or been in operation in the United States. About 80 percent of the plants have flows
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of 1 MOD or less; 70 percent of these have flows of 0.5 MOD or less. Cleveland, Tennessee,
has the largest plant in this country, with a design capacity of 9.2 MOD.
SBR technology evolved rapidly in the United States during the 1980s. Today, there are
five major vendors of SBR equipment: Austgen Biojet (ABJ), Aqua Aerobics, Fluidyne,
JetTech, and Transenviro. These manufacturers provide considerable variation in tank
configurations, system hydraulics, aeration, mixing techniques, effluent discharge equipment, and
sludge wasting methods. Numerous variations of SBR technology are currently in use. Most
systems use a number of different operating sequences to accommodate a range of influent flow
rates and automatically vary operations in response to changes in influent flow rate or allow
operator-initiated changes in either total cycle or phase times.
Continuous feed and intermittent discharge systems. One type of SBR system is the
continuous feed and intermittent discharge system (CFID). In this approach, the reactor
receives influent wastewater during all phases of the treatment cycle. When a system has more
than one reactor, which is common in municipal systems, the reactors work in parallel and
receive equal amounts of influent. Figure 32 illustrates a typical ABJ CFID system for a two-
reactor SBR plant. In this system, one SBR aerates, while the other settles and decants, so the
system needs only one blower to aerate both reactors. For a four-reactor system, the individual
reactor cycles usually are operated in such a way that the treatment plant discharge is
continuous.
«%
The dry weather flow cycles for most of the CFID systems evaluated by EPA were most
often set at either 3 or 4 hours. Typically, 50 percent of each cycle is devoted to aeration, 25
percent to settle, and 25 percent to decant. Facilities often use 2-hour cycle times to
accommodate stormwater flows.
In CFID systems, the settling and decant phases begin according to a preset cycle times.
Because inflow rates can vary during aeration and settling, the top water level, which occurs at
the start of the decant cycle, can also vary. The volume decanted during each cycle includes
both the reactor volume between the top and bottom water levels for that cycle and whatever
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Influent
Row
Liquid
Depth
Reactor
Operation
Influent
Flow
Liquid
Depth
Reactor
Operation
REACTOR NO. 1
Top Water Level
Bottom Water Level
Aerate
Settle
Decant
REACTOR NO. 2
Top Water Level
Bottom Water Level
Settle
Decant
Aerate
FINAL EFFLUENT DISCHARGE
Time (One SBR Cycle)
Figure 32. Typical Operation for a 2-Reactor CFID System
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inflow volume occurred during the decant phase itself. For the system depicted in Figure 32,
the actual discharge flow rate of the effluent for one cycle is twice the plant influent flow rate
during the same cycle because the two SBR reactors discharge only 50 percent of the time.
Because inflow is continuous in a CFID system, a key design consideration is to minimize
short circuiting between influent and effluent. Therefore, influent and effluent discharge
operations are often located at opposite ends of rectangular reactors, with length to width ratios
of about 2:1 to 3:1. A standard feature of the ABJ CFID systems is a prereact chamber
separated from the main react chamber by a baffle wall.
Intermittent flow and intermittent discharge systems. In the United States, the intermittent
influent flow and intermittent discharge (IFID) systems are sometimes referred to as the
conventional or "true" SBR systems. A common characteristic of all IFID systems is that the
influent flow to the reactor is discontinued for some portion of each cycle.
Figure 33 depicts a typical IFID system for a plant containing two SBRs. Each reactor
in this system operates with five discrete phases during a cycle, including fill, react (continuous
aeration), settle, decant, and idle. When influent wastewater is first added to the reactor during
the fill phase, any combination of aeration, mixing, and quiescent filling may occur. A mixing
phase independent of aeration is accomplished by using a jet aeration system (a JetTech
approach) or separate mixers (an Aqua Aerobics approach). Some variations of this system
distribute the influent over a portion of the reactor floor so that the influent will contact the
settled solids during unaerated and unmixed fill. The end of the fill cycle is controlled by
either a preset length of time or volume. To accommodate a range of influent flow rates and
automatically vary the time allocated to aerate, mix, and fill, many IFID systems use a
programmable logic controller (PLC). The PLC uses data on plant influent flow or the rise
rate in the reactor determined by a series of floats.
At the end of the fill phase in this system, the influent flow to the first reactor stops, and
the plant influent flow diverts to the second reactor. In IFID systems with a dedicated react
phase, continuous aeration occurs for about 1 to 3 hours, after which the mixed liquor settles
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Influent
Row
Liquid
Depth
Reactor
Operation
Influent
Flow
Liquid
Depth
Reactor
Operation
REACTOR NO. 1
H
Top Water Level
Bottom Water Level
RII
React
Settle
Decant
REACTOR NO. 2
Top Water Level
Bottom Water Level
React
Settle
Decant
Idle
Fill
FINAL EFFLUENT DISCHARGE
Idle
Time (One SBR Cycle)
Figure 33. Typical Operation for a 2-Reactor IFID System
with Fill, React, Settle, Decant, and Idle Phases
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under quiescent conditions for 30 to 60 minutes. Clarified effluent then decants from the tank
at a controlled rate (fixed or variable), to limit the disturbance of the settled mixed liquor, and
continues until the bottom water level is reached. The idle period occurs after the decant
phase is completed and before the influent flow is again redirected to a given reactor. The idle
phase is often minimal during periods of high flow.
For the system depicted in Figure 33, the actual discharge flow rate can be several times
higher than the influent flow rate. For example, if the two-reactor system typically has cycle
times of 3, 1, 0.75, 0.75, and 0.5 hours for the fill, react, settle, decant, and idle phases,
respectively, the actual discharge flow rate is four times the average influent flow rate. Plant
designers must carefully plan discharge flow rates to determine the capacity of downstream
hydraulics and the disinfection or filtration systems.
A typical Fluidyne IFID system does not have a dedicated react phase, and the amount of
time allocated to aeration, mixing, or quiescent filling during the fill phase varies. Once the
reactor fills to the top water level (based upon either a predetermined time or liquid level), the
flow is immediately diverted to the second reactor, aeration ceases, and settling begins.
A Transenviro IFID approach typically treats domestic wastewater with a 4-hour cycle (2
hours of aeration and 2 hours of non-aeration), and stormwater flows with a 2-hour cycle.
Influent enters the reactor at all times except for the decant phase, so that normal system
operations consist of the following phases: fill - aerate; fill - settle; no fill - decant; fill - idle.
These systems are also configured with an initial captive selector compartment that operates at
a constant or variable volume and serves as a flow splitter in multiple basin systems. The
system directs biomass from the main aeration zone to the selector.
Table 26 shows a typical operating strategy for a two-reactor JetTech IFID system
designed for a flow of 1 MOD. In this system, the influent flow rate determines the cycle
protocol. As the influent flow rate changes, both the total cycle time and the time allocated to
specific cycle operations change. During the decant phase, influent does not enter the reactor
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TABLE 26
TYPICAL JETTECH OPERATING STRATEGY
Phase
Filled Decant (hrs)
Anoxic Fill (hrs)
Aerated Fill (hrs)
React (hrs)
Settle (hrs)
Non-Fill Decant (hrs)
Idle (hrs)
Total Cycle (hrs)
% Cycle with Influent
0.5
0
3.0
1.0
1.0
0.75
0.31
1.94
8.0
50
Flow, MGD
1.0
0
2.44
0.81
1.63
0.75
0.50
0.38
6.52
50
3.0
0.81
0.27
0.81
1.08
0.75
0.06
0
3.79
50
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at design flow rates or below. At three times the design flow, the system introduces influent
into the bottom of the reactor for the majority of the decant cycle (0.81 hours).
SBR systems can also be designed for nitrification/denitrification and enhanced biological
phosphorus removal and be configured to switch from IFID operation to CFID operation when
necessary to accommodate stormwater flows or to allow a basin to be removed from service.
Decanters. Although early decanters faced significant problems, SBR equipment manufacturers
have made significant improvements in their respective decanting systems. Today, the Aqua
Aerobics system is a large floating plug valve, where the seat for the valve located in the
bottom section of the decanter is driven down during the decant phase. This system allows
wastewater to enter from below the wastewater surface and flow up over an internal discharge
weir. ABJ and Transenviro systems use mechanically driven decanters that are raised and
lowered as required; scum baffles prevent surface scum from mixing with the discharge. The
Fluidyne decanter is mounted on the reactor wall, and a solenoid-operated air valve starts the
decant phase. Throughout the Fluidyne decant phase, wastewater enters the decanter at the
bottom water level. The JetTech decanter is basically a draw tube that attaches to a set of
floats so that it remains below the liquid surface.
Influent Distribution. Some influent systems are simple configurations with just a pipe through
the reactor wall with a small structure to deflect the influent flow downward into the main SBR
»
reactor. Other systems use prereact tanks or captive selectors to achieve a higher food-to-mass
(F:M) ratio at the head of the reactor. Still other systems, such as the JetTech system, have
combined the influent distribution and sludge withdrawal piping so that influent can be
distributed up through the sludge blanket during anoxic fill.
Aeration. Fine bubble, coarse bubble, jet aeration, and mechanical aeration systems are all
being used in SBR facilities. Some systems, such as Aqua Aerobics, use a mixer to provide
independent aeration and mixing if desired. Jet aeration systems also allow for this capability.
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System Performance. The EPA study found that a number of SBR facilities experienced some
mechanical problems with the jet aeration equipment, diffusers, solenoid valves, and several
decanters, but no system had any major process failures. Operator satisfaction was extremely
high, as well. Preliminary analysis of effluent data indicates that SBR facilities often achieve
high quality effluent. EPA must analyze the data further to fully correlate effluent
characteristics with process characteristics. This analysis is now underway.
For more information on SBR technology, contact Jim Heidman (see Appendix A).
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APPLICATIONS OF LAGOONS AND OVERLAND FLOW
TREATMENT TO SMALL COMMUNITIES:
EMMITSBURG, MARYLAND - A CASE HISTORY
Carroll L. (Duke) Martin, Director of Public Works
Town of Emmitsburg, Maryland
To upgrade its wastewater treatment plant facility, the town of Emmitsburg, Maryland,
has combined the use of lagoon stabilization ponds, overland flow (OF), and the reuse of
treated effluent for crop irrigation. After only 1 year of operation, the system has shown
encouraging and satisfactory results. A schematic diagram of the Emmitsburg system is shown
in Figure 34.
Lagoons have been used in the United States since 1901, and over 7,000 ponds exist in
this country today to treat wastewater. Overland flow is a relatively new technology that
involves applying wastewater to the upper reaches of grass-covered slopes, which then flows
over the vegetated surface into runoff collection ditches. The OF process is best suited to sites
having relatively impermeable soils, although it has been used successfully on moderately
permeable soils with relatively low physical, chemical, and biological means, and where
wastewater flows in a thin film down the length of the slope. Figure 35 is a schematic view of
the Emmitsburg OF treatment system, which indicates that there is relatively little percolation
due to the presence of impermeable clay soil. Effluent that runs off from the OF system is
stored in a large holding pond (irrigation system reservoir) until it is applied to crops.
Emmitsburg decided to use the OF effluent to irrigate crops during the summer because
it seemed easier and more cost efficient to meet the acceptable limits for irrigation rather than
the stringent effluent limits for stream discharge. The crop irrigation system is composed of
center pivot irrigators in separate fields and covers a total of 210 acres. Although the summer
of 1989 was relatively wet, 13 million gallons of treated wastewater were used for irrigation
purposes, over 9 million gallons during the month of August alone. Application rates ranged
from 3/16 to 1/2 inch per week.
-189-
-------
}HD-
MFLUENT CHAMBER
V_CREAMERr RD WWPS
DISTRIBUTION CHAMBER X.
]
L
T 1
LAGOON NO 1 « 1
)VERLAND FLOW SYSTEM"^ \Jl
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I
TERRACE ** «* TERRACE
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-1 « . J
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-5 j=fi
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-x 1 LdOCON NO 3 j j jLAGOCN NO 4 ^
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^. x- - TOMS __ -.
^ - -" ~- ^
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'
^M--
*-
^_
-,__
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\
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w
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r»*
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CONTROL
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\
N
"»-,
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\
( IRRIGA1
\HESER\
IRRIGATION
PUMPING STATION
TREATMENT" PLANT
PUMPING STATION
CHLORINE CONTACT TANK
DE-CHLORINATION TANK
POST AES1TION TANK
CENTER PIVOT CROP
IRRIGATION AREAS
-------
ACCESS ROAD
EVAPCrTRANSPIRATWKl
PEEDS CAMA^Y
CLAV SOIL
COMPACTED TO
CDUECT\OKi
Top
"
OF APPUED
Figure 35. Schematic of the Emmitsburg, Maryland, Overland Flow System
-------
System performance. The facility has seasonal effluent limitations for surface water discharge.
Winter parameters, from October 1 through April 30, and summer parameters, from May 1 to
September 30, are shown in Table 27. Ground-water discharge parameters from May through
September also are shown in Table 27.
From October 1988 through April 1989, when the facility used the series lagoon system,
the effluent BOD averaged 19 mg/L per month. From May through September, 1989, when
the overland flow system was used, the average BOD was 7 mg/L and TSS was 15 mg/L. Prior
to being pumped to the spray field, the BOD in the storage reservoir averaged 4 mg/L, TSS
measured 5 mg/L, and the average TKN for the summer period was 2 mg/L. The water in the
irrigation storage reservoir thus proved to be a higher quality than the water in the lagoon
system. The crop irrigation system performed as expected during its first summer of operation.
Unfortunately, the results from the overland flow area could not be correlated with
application rates because the Emmitsburg facility lost the use of a magmeter, which measured
the flow of wastewater to the overland flow area.
Problems encountered. The Emmitsburg facility encountered several problems during the first
year of system operations. An extremely wet spring and early summer in 1989 greatly affected
tha>OF and crop irrigation systems. Consequently, attempts were made to store the wastewater
in the lagoons, which had been drawn down to relatively low levels by May 1 to accommodate
moderate wet weather conditions. (The system was designed for the wettest year in 10.) As
the wet weather continued, the storage space was depleted, requiring the lagoons to discharge
effluent to the stream. The facility could not meet the stringent 3 mg/L BOD level required
during spring and summer with only lagoon treatment.
During extremely wet summer conditions, increased storage of wastewater may not be
possible or cost effective. Discharging from the irrigation storage reservoir, however, would
more closely satisfy the town's surface water discharge limits. This option can be economically
accomplished by using one of the irrigation system pumps and modifying some existing piping,
-192-
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TABLE 27
WINTER, SUMMER, AND GROUND-WATER PARAMETERS FOR THE
EMMITSBURG, MARYLAND, WASTEWATER TREATMENT FACILITY
(MONTHLY AVERAGES, 1989)
Parameter
BOD, mg/L
TSS, mg/L
TKN
Total N, mg/L
DO, mg/L
PH
Fecal Coliform,
Winter
(10/1-4/30)
30
30
NA
NA
5.0(minimum)
6.5-8.5
20
Summer
(5/1-9/30)
3
30
30
NA
7.0(minimum)
6.5-8.5
200
Ground-Water
(5/1-9/30)
30
30
NA
10
NA
6.0-8.5
200
mpn/100 ml
-193-
-------
to enable the irrigation reservoir effluent to be processed in the same manner as the lagoon
effluent.
Consideration also should be given to relaxing permit requirements and basing them on
increased stream flow during a rain event or extended wet weather. Installing a gauging station
to measure stream flow may prove cost effective compared to providing increased storage
capacity. Emmitsburg is presently requesting that EPA incorporate this condition in the town's
NPDES permit, which is up for renewal.
A problem experienced in the overland flow system was that some applied wastewater
flowed away from the terrace and across an adjacent access roadway. This was due to the
relatively flat cross slope of the terrace at the application point and the lack of positive
drainage of the "splash block" (made of crushed stone) toward the terrace. System managers
have not yet resolved this problem; however, they are planning to install treated timbers on the
upper side of the crushed stone to divert wastewater back toward the terrace.
Costs. Actual project costs for the Emmitsburg system are shown on Table 28. Although
capital costs are comparable to conventional treatment facilities, Emmitsburg anticipates that
operation and maintenance costs will be lower because maintenance of the Emmitsburg system
is not labor intensive. Presently, two full-time employees (a certified operator and a trainee)
operate and maintain the system, and system managers anticipate that additional full-time
assistance will not be required.
O&M costs for FY90 are expected to be about $114,000. An additional $106,000 is
needed to amortize debt service, for a total budget of $220,000. Sewer user fees average $150
per year for residences (738 connections), which is favorable to the users. The remainder of
the income is paid by major system users (institutions, schools, etc.) and new users, for
connection fees.
Conclusions. Treatment results from the Emmitsburg system have consistently met the NPDES
permit requirements. The overland flow treatment area has performed as expected in reducing
-194-
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TABLE 28
ACTUAL COST PROJECTIONS FOR THE EMMITSBURG, MARYLAND,
LAGOON, OVERLAND FLOW, AND WATER REUSE SYSTEMS
Design Engineering $ 350,000
Construction 6,250,000
Equipment 310,000
Land 194,000
Construction/Startup
Engineering 660,000
Misc. (Admin., Legal, etc.) 50.000
Total $ 8,264,000*
3 The local share after EPA and Maryland State grant reimbursements is approximately
$1,000,000.
-195-
-------
nitrogen to acceptable levels and has surpassed the expectations of facility managers for BOD
removal.
The crop irrigation system has proven to be a reasonable alternative for disposing of
treated effluent during the summer months when stream discharge requirements are extremely
stringent. The crop production benefit of the crop irrigation system can be easily demonstrated
as well. By irrigating crops with treated wastewater effluent, Mason Dixon Farms has doubled
and tripled their expected yields during several growing seasons. During the dry summer of
1988, while other farms in the area reaped 3 to 5 tons per acre of barley and corn silage,
Mason Dixon Farms harvested 16 tons and 31 tons, respectively.
Due to battles over water rights, recent dry growing seasons, and the pressure on
agriculture to produce more crops, or at least as many, from an ever-decreasing amount of
farmland, reusing treated effluent for crop irrigation is a viable way to use treated wastewater.
The irrigation system can also remove some of the weather uncertainties and provide the
farmer with some assurance that crops will be produced even in a dry year. This benefit, in
itself, could prevent a farm from disappearing (to development) due to bankruptcy and help
maintain a balance of open space in the environment.
Small communities, when planning expansion or upgrading of their wastewater treatment
facilities, should not hesitate to consider land treatment and disposal. Based on the availability
and cost of land for the system, capital costs for construction should be comparable to
conventional systems.
For more information about this system, contact Duke Martin (see Appendix A).
-196-
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REVIEW OF LAGOON UPGRADES IN MISSOURI
Howard D. Markus and Terris L. Gates
Missouri Department of Natural Resources
Jefferson City, Missouri
Several methods used to upgrade lagoon wastewater treatment systems treat the lagoon
effluent rather than increase the treatment capability of the lagoon itself. These methods
include submerged rock filters, intermittent sand filters, slow sand filters, microscreens, and land
application.
In Missouri, 347 municipal lagoon facilities have obtained permits and have been
upgraded or will be upgraded to meet NPDES discharge limits. For existing lagoons, Missouri
has applied the NPDES provision to revise the lagoon limits up to a maximum of 45 mg/L
BODs and 80 mg/L nonfilterable residue (NFR) when allowed by water quality standards. For
those facilities that can achieve higher levels of treatment, however, more stringent permit limits
have been required (e.g., 30 mg/L BODs and 60 mg/L NFR).
This study surveyed a number of unique lagoon upgrades that applied the treatment
capability of the existing facilities, required low capital construction costs, and provided low
annual operating costs. The study team analyzed the Discharge Monitoring Reports submitted
to the Missouri Department of Natural Resources (MO-DNR) by the municipalities to compare
the 5-day BODs and NFR data before and after the lagoon upgrades were completed. The
lagoon facility parameters and study results are shown in Table 29.
Conclusion. The findings of this work indicate the following conclusions:
It is possible to upgrade lagoon systems by methods that do not conform to
normal design standards. These upgrades are unique to each facility and require
careful and conservative planning by the designer.
The designer should consider the operating volume that the sludge displaces in
the existing lagoon cells, as well as the nutrient load the sludge may add to the
cells.
-197-
-------
TABLE 29
LAGOON SYSTEM UPGRADES IN MISSOURI
Dile
Original
City/ System
County Built
Albany/ 1963
Gentry
Canton/ 1969
Lewis
Lancaster/ I960
Schuyler
Operating
Type or Depth
Facility (ft)
2-cell waste 3
stabilization
lagoon; 9.1-
acre 1" cell;
2.7-acre 2° cell
11.9-acre 4
1" cell; 2.3 ft.
and 4.3 ft
drawoffs
4 8 acre single 3
cell
Estimated Average BOD,
Population Dully Loading It) BOD,/
Served Mow (Ib/day) Acre
2,200 220,000 374 41 in
(June gpd 1* cell
1983-
May
1985)
NA NA NA NA
80S NA 137 28
(1986)
Date of Type of
Upgrade Upgrade
May I98S 46-acre aeration
basin, 10 ft
operating depth;
3.5-hp surface
aerators; 6.8
day DTIME; no
sludge removed
June 198S Multiple drawoffs
at 1.4-fl, 3 ft,
and 5-fl levels
August 1.9-acrc 2° cell;
1986 S-fl operating
depth; multiple
drawoffs at 2-, 4-,
S-fl depths; no
sludge removed
Added
Aeration
Capacity BOD, NFR
(Ib 0,/lb Permit Permit
BOD, Umit Umll
Removed) (mg/l.) (mg/l.) Results
4 30 60 Notable
improvement
in BOD,
NA 45 80 No significant
improvement
to BODj or
NFR effluent
quality
NA 45 80 Significant
improvement
to lagoon
discharge
-------
TABLK 29 (Conl.)
Dale
Original Operating
City/ System Type of Depth
County Built Facility (ft)
Maryville/ 1969 2 37-acre parallel 3
Nodaway 1° cells;
20-acre 2" cell;
16-acre 3° cell
Memphis/ 1969 15-acre single 5
Scotland cell
Estimated Average BOD,
Population Dally Loading IJ> BOD,/ Date of Type of
Served Flow (Ib/day) Acre Upgrade Upgrade
NA 1.6 1,267 17 December Aerated cell; 3.4-
MGD (1° 1985 acre surface area;
cells) 16-ft operating
depth; 2 centri-
fugal aeration
blowers each with
a 2,000 scfm
capacity; 80 static
lube diffusers on
lagoon floor; 8-day
DTIME; no sludge
removed
2,100 NA 33 24 January Original lagoon
(1980- 1986 divided into
1988) 10.7-acre 1" cell,
3.2-acre 2" cell,
1.1-acre 3° cell,
by polymer-coaled
fabric material
curtains; a sub-
merged 20 fl long,
8-inch perforated
pipe added to
effluent structure;
no sludge removed
Added
Aeration
Capacity BOD, NFR
(Ib
-------
lAlll.l; 29 (Cunt.)
Dale
Original
City/ System
County Built
Smilhville/ 1960
Clay
Southwest 1969
City/
McDonald
Sweet 1960s
Springs/
Saline
KEY 1°
r
3°
BOD,
DTIME =
Operating
Type of Depth
Facility (ft)
9.4-acre single 3
cell
2.3-acre 1* cell; 3.8
0.7-acre 2° cell
91- acre single 2-3
cell
primary
secondary
tertiary
biological oxygen demand
detention lime
Estimated Average BOD,
Population Dally Loading
Served Flow (Ib/day)
2.200 .22 MOD; 374
.25 MOD
(1986)
550 0.04 94
MOD
1,740 90,000 296
(1986) gpd
ft = reel/fool
gpd = gallons per day
hp = horsepower
NA = information not available
or not applicable
Added
Aeration
Capacity BOD, NFR
(Ib OJIb Permit Permit
Lb BOD,/ Date of Type of BOD, Limit Umlt
Acre Upgrade Upgrade Removed) (mg/1.) (mg/L)
40 November 0.9-acre aerated 1.5 NA NA
1986 cell; 12-ft operating
depth; 3 5-hp aerators;
9.4-day DTIME; operating
depth increased to 5 ft
in original cell; no
sludge removed
41 March Added 4 l-hp and 1 1.9 30 60
(1° cell) 1984 3-hp aerator to 1°
cell; 6.5-day DTIME;
no sludge removed
38.5 Fall 0.34-acre aeration 1.6 4.5 70
1987 cell; 6-fl operating
depth; 3-hp floating
mechanical aerators,
existing cell divided
into 5.0-acre 1° cell,
2.6-acre 2° cell, 1.5-
acre 3° cell, with
membrane partitions;
5.4-day DTIME; no
sludge removed
NhK = nonfillcrablc residue
MGD = million gallons |>cr day
O; = oxygen
scfm = standard cubic feet per minute
Results
Marked
improvement
to BODS; NFR
not improved
BOD, and NFR
were reduced
in the effluent
BOD, and NFR
effluent
parameters
improved
-------
The aerated lagoon typically had a 6- to 10-day detention time and significantly
reduced the BODs during the summer months. Designers should make sure that
adequate aeration capacity is available during these months and that the aeration
capacity can be lowered during the winter months.
Modifying the outlet structure to provide multiple withdrawal elevations on
facultative lagoons, without other modifications, will probably not provide the
desired reductions in BODs and NFR values.
Contact Terris Gates (see Appendix A) for a more complete report of this study which
contains system schematics and monthly BOD5 and NFR data.
-201-
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CITY OF SANFORD, FLORIDA, WATER RECLAMATION FACILITY,
RECLAIMED WATER SPRAY IRRIGATION SYSTEM, AND
VACUUM SEWER COLLECTION SYSTEM
William A. Simmons, Engineering and Planning Department
Sanford, Florida
The City of Sanford is located in central Florida on Lake Monroe, about 20 miles north
of Orlando. It has a population of about 30,000 with about 9,300 sewer accounts. The
municipal wastewater treatment plant service area is 305 acres in an established downtown
residential and commercial area. To comply with several Consent Orders from the Florida
Department of Environmental Regulation (FDER), by the end of 1995, Sanford must stop
discharging any nutrients into Lake Monroe and eliminate its combined sewer overflow (CSO)
system. "*
Sanford's existing sewer collection system consists of a gravity interceptor, lift stations,
and force mains, which convey the wastewater to a water reclamation area. Part of the older
city is served by a combined sanitary/stormwater sewer system, which allows mixed overflow to
discharge into the lake during high storm conditions. Based on technical and financial
feasibility, cost effectiveness, and a review of other systems already in operation in other parts
of the country, the city chose to install a new vacuum sewer collection system and rehabilitate
the existing combined system for stormwater flow as the most appropriate plan for CSO
*\
elimination. The city chose the vacuum system because of its ability to bypass horizontal and
vertical obstacles and overcome flat or adverse grade conditions.
After investigating numerous disposal options for eliminating effluent discharge into the
lake, including deep-well injection, use of effluent as plant cooling water, ocean outfall, reuse of
potable water, wetlands treatment, and land application, the city chose land application of
reclaimed wastewater as the optimum solution. Because of the limited availability of suitable
land in the area, the city must use a combination of low rate irrigation in both public access
and restricted areas.
-202-
-------
Vacuum sewer collection system. The design capacity of the vacuum collection system is about
1.2 MOD. The system consists of 42,526 lineal ft of vacuum line connected to 433 vacuum
interface valves (AirVac) located predominantly in fiberglass pits with traffic-bearing covers (see
Figures 36 and 37). There are 9 vacuum interface valves in concrete buffer tanks and 44
division valves. The system is divided into six separate vacuum mains arriving at the single
vacuum collection station. The vacuum station will be able to accommodate a seventh line at a
later date, if necessary.
The vacuum station (Figure 38) consists of a 5,000 gal vacuum collection tank placed
under vacuum by three 430-cfm vacuum pumps. Dual 800-gpm sewage pumps convey sewage
flows from the vacuum collection tank through a forcemain into the conventional gravity sewer
system. There are also three tributary conventional 300 to 500 gpm lift stations.
X*
Construction of the system is divided into three contracts by work type; one to build the
vacuum main, one for the vacuum station, and for the lateral replacement work. Construction
costs are $2,703,000 for the vacuum sewer collection main, $833,500 for the collection station,
and $525,000 for the laterals contract.
Water reclamation facility. Improvements to the water reclamation facility include the addition
of a flow splinter box; third secondary clarifier; another return/waste sludge pumping station;
alum storage and pumping facilities; tertiary filtration; chlorine contact chamber for high level
*\
disinfection; reclaimed water transfer pump station, quality control building, and distribution
pump station; chemical equipment building; and two 1.5-MG reclaimed water storage tanks.
Design wastewater flows for the facility are 7.3 MGD annual average daily flow and 15.5
MOD peak hourly flow. The "complete-mix" activated sludge process provides secondary
treatment and filtration prior to effluent disposal by spray irrigation. The process operations
used at the facility are as follows:
Preliminary treatment, including screening with a coarse bar rack and aerated grit
removal
-203-
-------
BREATHER DOME
LOCATED ABOVE
FLOOO LEVEL
.-GALVANIZED OR
POLYETHYLENE BREATHER
MASS CONCRETE
CAST IRON FRAME AND LID
RATED FOR H20 LOADING
ANTI-FLOTATION
COLLAR
&/&/&M
FIBERGLASS VALVE PIT
3" NO-HUB COUPLING (2)
§
;
1C
A
i^__^
n
CAP BONO
p
GRAVITY SEWERS FROM
1-i HOMES
6* MIN
3" SUCTION UNE
Figure 36. Sanford, Florida, Vacuum Sewer Collection Valve Pit
with Above-Ground Breather
-204-
-------
/it=nt=tn
4" VENT NEXT TO HOME
VACUUM'COLLECTION PIT
WITH 3" INTERFACE VALVE
AND ABOVE GROUND BREATHED
SCHEDULE 40 PVC
GRAVITY LINE MUST
NOT HAVE ANY TRAPS
TO BLOCK VENTING
VACUUM MAIN
Figure 37. Sun ford, Florida, Vacuum Sewer Collection System Gravity Line Connection to
Vacuum Valve Pit
-------
CONTROLS AND
ALARMS
TELEPHONE
ALARM
STANDBY
GENERATOR
K)
8" INTERFACE VALVE
VACUUM
RESERVOIR/
MOISTURE
REMOVAL
TANK
SUMP IN BASEMENT
OF VACUUM STATION
-X4
nn rjn nn
VACUUM PUMPS
VACUUM GAUGE
VACUUM SWITCH
COMPOUND GAUGE
1 y.R j VACUUM RECORDER
SG. SIGHT GLASS
NC. NOflMAlLY CLOSED
NO. NORMALLY OPEN
Figure 38. Sanrord, Florida, Vacuum Sewer Collection Station Line Diagram
-------
Secondary treatment, including aeration of the mixed liquor, final clarification,
and disinfection by chlorination
Tertiary filtration, including alum addition, tertiary filtration (dual media), and
high level disinfection
Sludge treatment, including aerobic digestion and sludge dewatering (belt filter
press system)
Stormwater treatment, including sedimentation, detention in open, lined basins,
and disinfection by chlorination
Figure 39 is a flow diagram of the facility.
Treatment efficiency in terms of BOD removal is expected to exceed 90 percent. The
TSS removal process is designed to result in the average effluent suspended solids concentration
of less than 5 mg/L, yielding a removal efficiency of 95 to 98 percent. Table 30 shows the
expected influent and effluent characteristics for the Sanford Water Reclamation Facility.
Reclaimed water program. Following the water reclamation process, highly treated wastewater
effluent called "reclaimed water," will be distributed throughout the planning area and used for
spray irrigation in both public and restricted access sites. Public access areas include golf
courses, city parks, school properties, residential neighborhoods, and commercial/industrial
establishments. A 2,000-acre site owned by the city and referred to as "Site 10" will be
developed as a "restricted access" agricultural reuse site to include orange groves and hay crops.
The original system contains about 85,000 linear ft of cement-lined ductile iron pipe
(DIP) ranging in size from 8 to 18 inches. Gate valves and butterfly valves are located
throughout the distribution system for isolating sections of the system and facilitating
maintenance and future extensions. The system also includes a wet weather discharge system,
which will be used when flows are high and irrigation use is low.
Reclaimed water is stored at the water reclamation facility, one of the golf courses, and
Site 10. The storage at the main facility consists of two 1.5-MG prestressed concrete tanks.
-207-
-------
UASTEUATER
ROW FROM
COLLECTION SYSTEM!
r
t
STORMWATER
ROWS OVER
15.5 mgd
STORMWATER
PUMPS
PRIMARY
CLARIFIES
STORMWATER
RETURN
PUMPS
"SUBSTANDARD*
WATER
I
+_
DETENTION
PONDS
«
ROWS HIGHER THAN
IRRIGATION I
STORAGE CAPACITY"
FILTER
PRESS
SLUDGE
PUMPS
SUPERNATANT
WASHWATER AND
FILTRATE
SPRAY IRRIGATION
MAYFAIR GOLFCOURSE
TTMACUAN GOLFCOURSE
PARKS I OTHER PUBLIC SITES
SITE 10 (AGRICULTURAL)
Figure 39. Flow Schematic of the Sanford, Florida, Water Reclamation Facility
-208-
-------
TABLE 30
EXPECTED INFLUENT AND EFFLUENT CHARACTERISTICS
FOR THE SANFORD WATER RECLAMATION FACILITY
Current
Year
Rerated
Row
Design
Row
Influent
a.
b.
c.
d.
e.
Average Daily Flow (MGD)
Maximum Daily Flow (MGD)
Peak Hourly How (MGD)
BOD5 @ AADP (Ib/day)
Suspended Solids (Ib/day) @ AADF
5.3
10.3
11.3
4,420
5,300
6.5
10.9
13.8
6,780
7,590
7.3
12.2
15.5 "
7,610
8,520
Effluent
a.
b. .
BOD5 @ AADF (mg/L)
(Ib/day)
Suspended Solids @ AADF (mg/L)
(Ib/day)
10
442
8
354
5
271
5
271
5
304
5
304
aAnnual average daily flow.
-209-
-------
Storage at the golf course consists of a lined pond incorporated into the landscape. Usable
volume for irrigation is 750,000 gal. The storage capacity at Site 10 is still being designed.
A booster pump station provides adequate pressures for the points of connection. The
station consists of two in-line turbine pumps set into the precast core structure located below
grade. The pumps are actuated when the pressure in the distribution system falls below the set
pressure.
The golf course uses new Rainbird sprinklers and controllers and an existing Toro
hydraulic irrigation system interconnected to the new pipe system and Rainbird equipment.
This course also installed a computer-operated irrigation system that can individually control
each head in the new system using the precipitation rates entered into the computer and the
Rainbird weather station information gathered from the golf course. The weather station **
measures rainfall and wind relativity. The city-owned properties and parks use Toro sprinklers
with Rainbird controllers.
The city initiated a public awareness campaign that has included a public notice to
determine customer interest regarding the future use of reclaimed water. Several
neighborhoods showed an overwhelming response to the program and, as a result, the city
already is designing an expansion system to allow residential irrigation to these areas.
Agricultural sites have also requested to be included in the program. All future developments
of the city must include provisions for irrigating with reclaimed water.
The City of Sanford Reclaimed Water Program is well underway. The response to the
program has been very positive from the customers, regulatory agencies, and other interested
parties. To obtain a more complete report about the Sanford water reclamation and vacuum
sewer project, contact William Simmons (see Appendix A).
-210-
-------
APPENDICES
-------
APPENDIX A
AGENDA AND LIST OF SPEAKERS
-------
U. S. ENVIRONMENTAL PROTECTION AGENCY
1990 MUNICIPAL WASTEWATER
TREATMENT TECHNOLOGY FORUM
March 20-22
Orlando, Florida
AGENDA
TUESDAY. MARCH 20. 1990
7:30 a.m. Registration
8:30 a.m. INTRODUCTION
Opening Remarks <-
Lee Pasarew, U.S. EPA Office of Municipal Pollution Control (OMPC),
Washington, DC
Irene Homer, Technology Network Coordinator, U.S. EPA OMPC,
Washington, DC
Region 4 Welcome
State of Florida Welcome
Robert Heilman, Department of Environmental Regulation, State of
Florida
Keynote Address
Jack Lehman, U.S. EPA OMPC, Washington, DC
9:45 a.m. Break
10:00 sun. SLUDGE MANAGEMENT TECHNOLOGIES
Session Chairman: Robert Bastian
Trends in Municipal Sludge Management Practices
Tim Shea, Engineering Science
Organic Contaminants and Land Application of Municipal Sludge
in Canada
Melvin Webber, Wastewater Technology Center, Environment Canada
Alkaline Pasteurization of Municipal Sludges for Beneficial Utilization
David S. Sloan, N-Viro Energy Systems
Odor Control for Composting
Roy Mcllwee, Smith Environmental Engineering
A-l
-------
12:00 p.m. WORKING LUNCHEON
International Activities
Lehman-Baltay-Pasarew
1:15 p.m. SECONDARY TREATMENT TECHNOLOGIES
Session Chairman: James Kreissl
ATAD - Auto Thermophilic Aerobic Digestion
Kevin Deeney, Junkins Engineering
Experience with CAPTOR
Elbert Morton, West Virginia Department of Natural Resources
Physical-Chemical Treatment for Secondary Effluent
Robert Sparling, City of Tacoma
BIOLAC - Biological Aerated Chain
Karl Scheible, HydroQual
3:15 p.m. BREAK
3:30 p.m. O & M Issues for POTWs
John Flowers, U.S. EPA, Washington, DC
Alternative Technologies at Iron Bridge Treatment Plant
Philip Feeney, Post Buckley Schuh Jernigan
Overview of National CSO Strategy
Harry Thron, U.S. EPA, Washington, DC
Combined Sewer Overflow Management for Region I
Richard P. Kotelly, U.S. EPA, Region I
Combined Sewer Overflow Plan for East Lansing MI
Chuck Pycha, U.S. EPA Region V
5:30 p.m. ADJOURN
A-2
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WEDNESDAY. MARCH 21. 1990
8:00 a.m. CONSTRUCTED WETLANDS FOR WASTEWATER MANAGEMENT
Session Chairman: Robert Bastian
Overview of Wetlands Treatment in the U.S.A.
Robert Kadlec, The University of Michigan
Design of Constructed Wetlands
Robert Kadlec, The University of Michigan
Randy Clarkson, State of Missouri
Operational Performance of Reedy Creek Wetlands Treatment System
and other Southern Wetlands
Robert L. Knight, CH2M-Hill
Bob Kohl, Reedy Creek Energy Services
Constructed Wetlands at Iron Bridge Treatment Plant **
JoAnne Jackson, Post Buckley Schuh Jernigan
Compliance with Permits for Natural Systems
Bob Freeman, U.S. EPA, Region IV
10:15 a.m. BREAK
10:30 a.m. Inventory of Constructed Wetland Systems in U.S.A. and WPCF Manual
of Practice on Natural Systems
Sherwood Reed, Consulting Engineer
11:00 a.m. DISINFECTION
Session Chairman: Robert Bastian
U.V. Disinfection
Karl Scheible, HydroQual
Region V Special Evaluation Project of Chlorination-Dechlorination
Chuck Pycha, U.S. EPA, Region V
12:00 p.m. LUNCH - On your own
12:00 p.m. I/A Coordinators Lunch and Meeting (12:00 - 2:30)
12:00 p.m. Small Flows Clearing House Demonstration of
Bulletin Board (12:00 - 2:30)
Anish R. Jantrania, University of West Virginia
A-3
-------
(Please choose one field trip to attend)
1:15 p.m. Leave hotel for Field Trip to Iron Bridge Treatment Plant, Orlando,
Highlighting:
a. - Biological Treatment for Phosphorus Removal
b. - 1000 Acres of Constructed Wetlands
Host: JoAnn Jackson, Senior Project Engineer,
Post Buckley Schuh Jernigan, Consulting Engineers
2:30 p.m. Leave Hotel for Field Trip to Reedy Creek Energy Services,
Highlighting:
a. - 9 MGD Taulman-Weiss In-Vessel Composting
b. - 100 Acres of Constructed Wetlands
Host: Bob Kohl
4:30 p.m. Leave Field Trip sites
5:00 p.m. Arrive at the hotel
A-4
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THURSDAY. MARCH 22. 1990
8:00 a.m. TOXICITY MANAGEMENT AT POTWs
Session Chairman: Atal Eralp
Technologies for Toxicity Removal at POTWs
Perry Lankford, Eckenfelder & Associates
Development of Computer Based Model and Data Base for Predicting the
Fate of Hazardous Wastes at POTWs
John Bell, Wastewater Technology Center
Environment Canada
Plant Performance Evaluation
Bill Cosgrove, U.S. EPA, Region IV
9:30 a.m. WASTEWATER TECHNOLOGIES FOR SMALL COMMUNITIES-
Session Chairman: Arthur Condron
EPA's Small Community Strategy
Ann Cole, U.S. EPA, Regional Operations, State and Local Relations,
Washington, DC
SCOT - Small Communities Outreach Technologies
Randy Revetta, U.S. EPA, Washington, DC
10:00 a.m. BREAK
10:15 a.m. New Developments for Small Community Sewer Systems
Dick Otis, Owen Ayres and Associates
Rich Naret, Cerrone & Associates
W.C. (Bill) Bowne, Bowne Associates
Community Mound Systems
Dick Otis, Owen Ayres and Associates
Sequencing Batch Reactors
James Heidman, U.S. EPA, Cincinnati, OH
Application of Lagoons + Overland Flow to Small Communities
Duke Martin, Emmitsburg, Maryland
Review of Lagoon Upgrades in Missouri
Terris Gates, State of Missouri
12:45 p.m. LUNCH-on your own
A-5
-------
1:45 p.m. Leave Hotel for Field Trip to Sanford Wastewater Treatment Plant,
Featuring:
a. - 0.3 MOD Vacuum Sewers
b. - 5 MOD Advanced Treatment Plant for Water Reuse
Host: William A. Simmons, City Engineer, City of Sanford
4:00 p.m. Leave Sanford Wastewater Treatment Plant
5:00 p.m. Arrive at Hotel
END OF FORUM
A-6
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U.S. ENVIRONMENTAL PROTECTION AGENCY
1990 MUNICIPAL WASTEWATER TREATMENT
TECHNOLOGY FORUM
Orlando, Florida
March 20-22, 1990
SPEAKER LIST
John P. Bell
Enviromega Limited
P.O. Box 121
Campbellville, Ontario
Canada LOP 1BO
(416) 336-6009
FAX (416) 336-4765
Paul Baltay
Municipals Facilities Division Director
Office of Municipal Pollution Control
U.S. Environmental Protection Agency
401 M Street, S.W. 20460
(202) 382-7260
W.C. Bowne
Consulting Engineer
2755 Warren
Eflgene, OR 97405
(503) 345-3001
Terris Gates
Missouri Department of Natural Resources
P.O. Box 176
Jefferson Building 2nd floor
Jefferson City, MO 65102
Randy Clarkson
Missouri Department of Natural Resources
P.O. Box 176
Jefferson Building 2nd floor
Jefferson City, MO 65102
Terry Crabtree
Eastern Regional Manager
Smith Environmental Engineering
P.O. Box 359
Broomal, PA 19008
(215) 356-5652
FAX (215) 328-4529
Ann Cole
U.S. Environmental Protection Agency
Office of Regional Operations and
State/Local Relations (A-101)
401 M Street, SW
Washington, DC 20460
(202) 382-4719
FAX (202) 475-9365
Bill Cosgrove
U.S. Environmental Protection Agency
Environmental Services Division
College Station Road
Athens, GA 30619
(404) 546-3626
FAX (404) 546-3343
Kevin Deeny
Junkins Engineering
P.O. Box 386
Morgantown, PA 19543
(215) 286-2825
FAX (215) 286-6400
A-7
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Philip Feeney
Post, Buckley, Schuh, & Jernigan
Winter Park Plaza
1560 Orange Avenue
Suite 700
Winter Park, FL 32789
(407) 647-7275
FAX (407) 740-8958
Robert Freeman
U.S. Environmental Protection Agency
345 Courtland Street, N.W. [4WM-MF]
Atlanta, GA 30365
(404) 347-3633
FAX (404) 347-5204
James Heidman
U.S. Environmental Protection Agency
26 M.L. King Drive
Cincinnati, OH 45268
(513) 569-7632
FAX (513) 569-7276
Robert E. Heilman
Florida Department of
Environmental Regulation
2600 Blair Stone Road
Tallahassee, FL 32399-2400
(904) 487-0563
JoAnne Jackson
Post, Buckley, Schuh, & Jernigan
Winter Park Plaza
1560 Orange Avenue
Suite 700
Winter Park, FL 32789
(407) 647-7275
FAX (407) 740-8958
Anish R. Jantrania
National Small Rows Clearing House
West Virginia University
P.O. Box 6064
Morgantown, WV 26506-6064
(800) 624-8301
Robert Kadlec
University of Michigan
Dept. of Chemical Engineering
Dow Building
Ann Arbor, MI 48109
(313) 764-3362
FAX (313) 763-0459
Bob Kohl
Reedy Creek Utility Company
5300 North Cast Drive
Lake Buena Vista, FL 32830
(407) 824-4026
FAX (407) 824-4529
Robert L. Knight
CH2MHill
7201 NW llth Place
P.O. Box 1647
Gainsville, FL 32605
(904) 331-2442
FAX (904) 331-5320
Richard P. Kotelly
Water Management Division
U.S. Environmental Protection Agency
Region 1
JFK Federal Building Room 2203
Boston, MA 02203
(617) 565-3482
FAX (617) 565-3468
Perry Lankford
Eckenfelder & Associates
227 French Landing Drive
Nashville, TN 37228
(615) 255-2288
FAX (615) 256-8332
A-8
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Jack Lehman
Deputy Director
U.S. Environmental Protection Agency
Office of Municipal Pollution Control
401 M Street, S.W. [WH-595]
Washington, DC 20460
(202) 382-3827
FAX (202) 382-3827
Duke Martin
P.O. Box 380
Emmitsburg, MD 21727
(301) 447-6116
FAX (301) 447-2333
Elbert N. Morton
West Virginia Dept. of Natural Resources
617 Broad Street
Charleston, WV 25301
(304) 348-0633
FAX (304) 348-3778
Rich Naret
Cerrone & Associates, Inc.
401 Main Street
Wheeling, WV 26003
(304) 232-5550
FAX (304) 232-2512
Hitesh Nigam
U.S. Environmental Protection Agency
40r M Street, S.W. [WH-546]
Washington, DC 20460
(202) 382-5822
FAX (202) 382-3827
Dick Otis
Owen Ayres and Associates, Inc.
2445 Darwin Road
Madison, WI 53704
(608) 249-0471
FAX (608) 249-2806
Charles J. Pycha
U.S. Environmental Protection Agency
Water Management Division
(5 WCT-TUB-9)
230 S. Dearborn Street
Chicago, IL 60604
(312) 886-0259
FAX (312) 886-9096
Sherwood C. Reed
Environmental Engineering Consultants
R.R. 1 Box 572
Norwich, VT 05055
(802) 649-1230
Randy Revetta
U.S. Environmental Protection Agency
401 M Street, SW [WH-595]
Washington, DC 20460
(202) 382-5685
FAX (202) 382-3827
O. Karl Scheible
HydroQual, Inc.
1 Lethbridge Plaza
Mahwah, NJ 07430
(201) 529-5151
FAX (201) 529-5728
Timothy G. Shea
Engineering - Science
Two Flint Hall
19521 Rosenhaven Street
Fairfax, VA 22030
(703) 591-7575
FAX (703) 591-1305
William A. Simmons
Engineering & Planning Dept.
P.O. Box 1778
Sanford, FL 32772-1778
(407) 330-5673
David Sloan
2139 University Drive
Suite 290
Coral Spring, FL 33071
(305) 341-0777
FAX (305) 341-0894
A-9
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Robert Sparling
City of Tacoma Sewer Authority
747 Market Street Suite 420
Tacoma, WA 98402-3769
(206) 591-5525
FAX (206) 591-5097
Harry Thron
Office of Water Enforcement and Permits
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, DC 20460
(202) 475-9536
Melvin D. Webber
Wastewater Technology Centre
Environment Canada
P.O. Box 5050
Burlington, Ontario
Canada L7R 4A6
(416) 336-4519
FAX (416) 336-4765
A-10
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APPENDIX B
LIST OF NATIONAL CONTACTS FOR WASTEWATER TECHNOLOGY, SLUDGE
TECHNOLOGY, AND OPERATIONS AND MAINTENANCE OPERATOR TRAINING
-------
APPENDIX B
LIST OF NATIONAL CONTACTS FOR WASTEWATER TECHNOLOGY, SLUDGE
TECHNOLOGY, AND OPERATIONS AND MAINTENANCE OPERATOR TRAINING
National Wastewater Technology Coordinator
Wendy Bell
USEPA OMPC (WH-595)
401 M Street, S.W.
Washington, DC 20460
(202) 382-7292
(FTS) 382-7292
Sludge Research Contact
Joe Farrell
USEPA-RREL
26 W. Martin Luther King Drive
Cincinnati, OH 45268
(513) 569-7645
(FTS) 684-7645
Sludge Coordinator
John Walker
USEPA OMPC (WH-595)
401 M Street, S.W.
Washington, DC 20460
(202) 382-7283
(FTS) 382-7283
Wastewater Management Coordinator
Randy Revetta
USEPA OMPC (WH-595)
40fM Street, S.W.
Washington, DC 20460
(202) 382-5685
(FTS) 382-5685
Wastewater Technology Contact
Jim Kreissl
USEPA-RREL
26 W. Martin Luther King Drive
Cincinnati, OH 45268
(513) 569-7611
(FTS) 684-7611
National Small Flows Clearinghouse Manager
V.
Steve Dix
P.O. Box 6064
Morgantown, WV 26506-6064
(304) 293-4191
(800) 624-8301
Wastewater Technology Data Base Manager
Charles Vanderlyn
USEPA OMPC (WH-595)
401 M Street, S.W.
Washington, DC 20460
(202) 382-7277
(FTS) 382-7277
O&M Operator Training
John Rowers
USEPA OMPC (WH-546)
401 M Street, S.W.
Washington, DC 20460
(202) 382-7288
(FTS) 382-7288
B-l
-------
APPENDIX C
LIST OF ADDRESSES FOR REGIONAL AND STATE WASTEWATER
TECHNOLOGY, SLUDGE, AND O&M COORDINATORS
-------
APPENDIX C
LIST OF ADDRESSES FOR REGIONAL AND STATE
WASTEWATER TECHNOLOGY, SLUDGE, AND O&M COORDINATORS
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION I
U.S. EPA Water Management Division
JFK Federal Building
Boston, MA 02203
Connecticut
Connecticut Department of Environmental
Protection
122 Washington Street
Hartford, CT 06106
Maine
Department of Environmental Protection
State House (STOP 17)
Augusta, ME 04333
Charles Conway
(617) 565-3517
(FTS) 835-3517
William Hogan
(203) 566-2793
Dennis Purington
(207) 289-7764
Charles Conway
(617) 565-3517
(FTS) 835-3517
Warren Herzig
(203) 566-3282
Brian Kavanah
(207) 582-8740
Charles Conway
(617) 565-3517
(FTS) 835-3517
Roy Fredricksen
(203) 393-2705
Don Elbert
(207) 283-78W
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
O
REGION I (Continued)
Massachusetts
Division of Water Pollution Control
Massachusetts Department of Environmental
Quality Engineering
One Winter Street
Boston, MA 02108
New Hampshire
New Hampshire Water Supply and Pollution
Control Commission
P.O. Box 95, Hazen Drive
Concord, NH 03301
Rhode Island
Rhode Island Division of Water Resources
291 Promenade Street
Providence, RI 02908
Robert Cady
(617) 292-5713
John Bush
(603) 271-2508
Warren Town
(401) 277-3961
Rick Dunn
(617) 556-1130
Rich Vlanders
(603) 271-2925
Chris Campbell
(401) 277-3961
Kim Simpson
(508) 727-8882
George Neill
(603) 271-3325
Ed Szymanski
(401) 277-3961
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION I (Continued)
Vermont
Environmental Engineering Division
Vermont Agency of Environmental Conservation
103 South Main Street, Bldg. 9 South
Waterbury, VT 05676
Marilyn Davies
(802) 244-8744
George Desch
(802) 244-8744
Christine Thompson
(802) 244-8744
O REGION II
U.S. EPA Water Management Division
26 Federal Plaza, Room 837
New York, NY 10278
New Jersey
New Jersey Department of Environmental
Protection
P.O. Box CN-029
Trenton, NJ 08625
John Mello
(212) 264-5677
(FTS) 264-5677
Robert Kotch
(609) 292-6894
Aristotle Harris
(212) 264-4707
(FTS) 264-4707
Helen Pettit Chase
(609) 633-3662
John Mello
(212) 264-5677
(FTS) 264-5677
Chris Hoffman
(609) 984-4429
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
O
REGION II (Continued)
New York
Technical Assistance Section
New York State Department of Environmental
Conservation
50 Wolf Road
Albany, NY 12233
Puerto Rico
Local Assistance Grants Section
Puerto Rico Environmental Quality Board
Banco Nacional Building
431 Ponce De Leon Blvd.
Hato Rey, PR 00913
Virgin Islands
Natural Resources Management Office
179 Altoona and Welqunst
Charlotte Amalie, St. Thomas
Virgin Islands 00801
Randy Orr
(518) 457-3810
Baltazar Luna
(809) 751-5540
Phyllis Brin
(809) 774-3320
Rick Hammand
(518) 457-2051
Arthur Warner
(518) 457-5968
Ava Hernandez
(809) 751-5540
Baltazar Luna
(809) 751-5540
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
n
REGION III
U.S. EPA Water Management Division
841 Chestnut Building
Philadelphia, PA 19107
Delaware
Delaware Department of Natural Resources and
Environmental Control
Division of Environmental Control
89 Kings Highway, Box 1401
Dover, DE 19903
District of Columbia
District of Columbia Department of Public Works
Water and Sewer Utility Administration
5000 Overlook Avenue, S.W.
Washington, DC 20032
Maryland
Department of Environment
Water Management Administration
2500 Broening Highway
Baltimore, MD 21224
Clyde Turner
(215) 597-8223
(FTS) 597-8223
Roy R. Parikh
(302) 736-5081
Leonard R. Benson
(202) 767-7603
John Milnor
(301) 631-3726
Kenneth Pantuck
(215) 597-9478
(FTS) 597-9478
William Razor
(302) 736-4781
Jim Kern
(215) 597-3423
Leonard R. Benson
(202) 767-7603
James R. Collier
(202) 767-7370
Doug Proctor
(301) 631-3375
Jake Bair
(301) 934-2251
ex. 402
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
O
6s
REGION 111 (Continued)
Pennsylvania
Pennsylvania Department of Environmental
Resources
Division of Municipal Facilities and Grants
P.O. Box 2063
Harrisburg, PA 17120
Virginia
Virginia State Water Control Board
Box 11143
Richmond, VA 23230
West Virginia
West Virginia Department of Natural Resources
Division of Water Resources
1201 Greenbrier Street
Charleston, WV 25311
Charles Kuder
(717) 787-3481
Walter Gills
(804) 367-8860
Elbert Morton
(304) 348-0633
William Pounds
(717) 787-7381
Cal M. Sawyer
(804) 786-1755
Clifton Browning
(304) 348-2108
Ken O'Korn
(717) 787-8184
Jack Vanderland
(804) 257-6436
Richard Weigand
(304) 348-3075
(304) 372-3400-
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
2
REGION IV
U.S. EPA Water Management Division
345 Courtiand Street, N.E.
Atlanta, GA 30365
Alabama
Alabama Department of Environmental Management
1751 Federal Drive
Montgomery, AL 36130
Florida
Bureau of Wastewater Management and Grants
Florida Department of Environmental Regulation
Twin Towers Office Building
2600 Blair Stone Road
Tallahassee, FL 32301
Georgia
Environmental Protection Division
Georgia Department of Natural Resources
Floyd Towers East, Suite 1058
205 Butler Street, S.E.
Atlanta, GA 30334
Bob Freeman
(404) 347-4491
(FTS) 257-4491
David Hutchinson
(205) 271-7761
Bhupendra Vora
(904) 488-8163
Ernest Earn
(404) 656-4708
Vince Miller
(404) 347-3633
(FTS) 257-3633
Cliff Evans
(205) 271-7761
J.N. Ramaswamy
(904) 488-8163
Mike Creason
(404) 656-4887
Normand Colon
(404) 347-3633
(FTS) 257-3633
Larry Bryant
(205) 277-3630
Barbara Mitchell
(904) 392-9570
Gaynell Hill
(404) 656-7400
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
p
60
REGION IV (Continued!
Kentucky
Kentucky Department of Environmental Protection
Division of Water
18 Rcilly Road
Frankfort, KY 40601
Mississippi
Municipal Facilities Branch
Mississippi Department of Natural Resources
Bureau of Pollution Control
P.O. Box 10385
Jackson, MS 39209
North Carolina
Division of Environmental Management
North Carolina Department of Natural Resources
and Community Development
P.O. Box 27687
Raleigh, NC 27611
Vince Borres
(502) 564-3410
Sitaram Makena
(601) 961-5171
Allen Wahab
(919) 733-6900
Art Curtis
(502) 564-3410
Billy Warden
(601) 961-5060
Dennis Ramsey/
Allen Wahab
(919) 733-6900
Nancy Fouser
(502) 564-3358
Glen Odom
(601) 961-5159
Ted Cashin
(919) 733-7015'
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
8
REGION IV (Continued)
South Carolina
Facilities Planning Environmental Quality Control
South Carolina Department of Health and
Environmental Control
2600 Bull Street
Columbia, SC 29201
Tennessee
Tennessee Department of Health and Environment
Terra Building, 3rd Floor
150 Ninth Avenue North
Nashville, TN 37247-3301
REGION V
U.S. EPA Water Management Division
230 South Dearborn Street
Chicago, IL 60604
Sam Grant
(803) 734-5279
Sam Gaddipati
(615) 741-0638
Charles Pycha
(312) 886-0259
(FTS) 886-0259
Mike Montebello
(803) 734-5262
Steve Sanford
(615) 741-0638
John O'Grady
(312) 353-1938
(FTS) 353-1938
Earl Hunter
(803) 734-5300
James Coe
(615) 898-8090
Eugene Chaijccn
(312) 353-2124
(FTS) 353-2124
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
O
K-k
O
REGION V (Continued)
Illinois
Division of Water Pollution Control
Illinois Environmental Protection Agency
2200 Churchill Road
Springfield, IL 62706
Indiana
Special Projects Section
Water Management Division
Indiana Department of Environmental Management
105 South Meridian Street, P.O. Box 6015
Indianapolis, IN 46206-6015
Michigan
Michigan Department of Natural Resources
State Office Bldg., Sixth Floor
350 Ottawa St., N.W.
Grand Rapids, MI 49503
James Leinecke
Terry Zeal
(217) 782-2027
Donald Dailey
(317) 232-8659
Ron Woods
(616) 456-5071
AJ Keller
(217) 782-16%
William H. Busch
(217) 782-16%
Dan Strahl
(317) 232-8736
Leonard Ashack
(317) 633-0756
Dale Brockway
(517) 373-8750
Howard Selovcr
(517) 243-4751
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION V (Continued)
Minnesota
Municipal Wastewater Treatment Section
Community Assistance Unit #3
Minnesota Pollution Control Agency
520 Lafayette Road
St. Paul, MN 55155
O Ohio
H-*
I«
Division of Construction Grants
Ohio Environmental Protection Agency
P.O. Box 1049
1800 Water Mark Drive
Columbus, OH 43266-10349
Wisconsin
Municipal Wastewater Section
Wisconsin Department of Natural Resources
P.O. Box 7921
Madison, WI 53707
Lori Frekot
(612) 296-8762
Margaret Klepic
(614) 644-2807
Bob Steindorf
(608) 266-0449
Jorja DuFresue
(612) 296-9292
Bill Sexauer
(612) 296-7218
Stuart M. Blydenburgh
(614) 644-2001
Scot Ankron
(614) 644-2014
Tom Portle
(608) 266-8343
Tom Kroehn
(608) 267-7656'
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION VI
U.S. EPA Water Management Division
Allied Bank Tower at Fountain Place
1445 Ross Avenue
Dallas, TX 75202
Arkansas
Arkansas Department of Pollution Control and
O Ecology, P.O. Box 9583
£ 8001 National Drive
Little Rock, AR 72219
Louisiana
Louisiana Department of Environmental Quality
333 Laurel St., Suite 420
Baton Rouge, LA 70801
New Mexico
New Mexico Environmental Improvement Agency
Water Quality Section
Harold Runnels Building
1190 St. Francis Drive
P.O. Box 968
Santa Fc, NM 87501
Ancil Jones
(214) 655-7130
(FTS) 255-7130
Martin Roy
(501) 562-8910
Robert Crawford
(504) 342-0067
Arun Dhawan
(505) 827-2809
Ancil Jones
(214) 655-7130
(FTS) 255-7130
Mike Hood
(501) 562-8910
Ken Fledderman
(504) 342-0067
Arun Dhawan
(505) 827-2809
Tom Reich
(214) 655-7130
(FTS) 255-7130
James Bailey
(501) 574-4550
Dirk Kavanaugh
(318) 265-5584
Hayward Martin
(505) 984-0676
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APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
0
I«
u>
REGION VI (Continued)
Oklahoma
Engineering Division
Oklahoma State Department of Health
3400 North Eastern Avenue
P.O. Box 53551
Oklahoma City, OK 73152
^ Texas
Texas Water Development Board
P.O. Box 13087
Capital Station
Austin, TX 78711-3231
H.J. Thung
(405) 271-7346
Milton Rose
(512) 463-8513
Denny Hodges
(405) 271-7362
Milton Rose
(512) 463-8513
Dr. William Roach
(405) 733-7364
Clark Benson
(409) 845-6246
REGION Vll
U.S. EPA Water Management Division
726 Minnesota Avenue
Kansas City, KS 66101
Rao Surampalli
(913) 551-7453
(FTS) 276-7453
Rao Surampalli
(913) 551-7453
(FTS) 276-7453
Katherine Tisdier
(913) 551-7450
(FTS) 276-7450
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION VII (Continued)
Iowa
Program Operations Division
Iowa Department of Natural Resources
Environmental Protection Division
Henry A. Wallace Building
900 East Grand
O Des Moines, IA 50319
Kansas
Municipal Programs Section
Division of Environment
Kansas Department of Health and Environment
Forbes Field, Bldg. 740
Topeka, KS 66620-0110
Missouri
Water Pollution Control Program
Division of Environmental Quality
Missouri Department of Natural Resources
P.O. Box 176
Jefferson City, MO 65102
Terry Kirschenman
(515) 281-8885
Rodney Geisler
(913) 296-5527
Douglas Garrett
(314) 751-5723
Darrell McAllister
(515) 281-8869
Rodney Geisler
(913) 296-5527
Ken Arnold
(314) 751-6624
Doug Feil
(319) 398-5678
Jerry Grant
(913) 296-5561
Lorene Boyt
(417) 451-3583
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION VII (Continued)
Nebraska
Construction Grants Branch
Water Quality Section
Nebraska Department of Environmental Control
P.O. Box 98922
Statehouse Station
Lincoln, NE 68509-8922
Mahmood Arbab
(402) 471-4236
Rick Bay
(402) 471-2186
Rick Bay
(402) 471-2186
REGION VIII
U.S. EPA Water Management Division
999 - 18th Street
Denver, CO 80202-2405
Colorado
Water Quality Control Division
Colorado Department of Health
4210 E. llth Avenue
Denver, CO 80220
Jim Brooks
(303) 293-1549
(FTS) 330-1549
Derald Lang
(303) 331-4564
Jim Brooks
(303) 293-1549
(FTS) 330-1549
Phil Hegeman
(303) 331-4564
Leon Malloy
(303) 293-1552
(FTS) 330-1552
Tom Feeley
(303) 980-9165
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
n
REGION VIII (Continued)
Montana
Water Quality Bureau
Montana Department of Health and
Environmental Sciences
Cogswell Building
Helena, MT 59620-0522
North Dakota
Division of Water Supply and Pollution
Control
North Dakota Department of Health
1200 Missouri Avenue, P.O. Box 5520
Bismark, ND 58502-5520
South Dakota
South Dakota Department of Water and
Natural Resources
Joe Foss Building, 523 East Capitol
Pierre, SD 57501-3181
Scott Anderson
(406) 444-2406
Scott Anderson
(406) 444-2406
Jeff Hauge
(701) 224-4827
Jeff Hauge
(701) 224-4827
Dave Templeton
(605) 773-4216
Dave Templeton
(605) 773-4216
Martha Ann Dow
(406) 265 7821
ext. 3285
Ralph Reidinger
(701) 244-2354
Bill Alsenbrey '
(605) 773-32%
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION VIII (Continued)
Utah
Utah Bureau of Water Pollution Control
P.O. Box 16690
Salt Lake City, UT 84116-0690
Wyoming
Water Quality Division
Wyoming Department of Environmental Quality
Herschler Bldg., 4 West
122 W. 25th Street
Cheyenne, WY 82002
Kiran L. Bhayani
(801) 533-6146
Mike Hackett
(307) 777-7781
Kiran L. Bhayani
(801) 533-6146
Mike Hackett
(307) 777-7781
Charles Tolson
(801) 226-5000
Bill Mixer
(307) 268-2368
REGION IX
U.S. EPA Water Management Division
1235 Mission St.
San Francisco, CA 94103
Arizona
Arizona Department of Health Services
2005 North Central Avenue
Phoenix, AZ 85004
Jim Plan
(415) 705-2121
(FTS) 465-2121
Ron Frey
(602) 257-2231
Lauren Fondahl
(415) 705-2199
(FTS) 465-2199
John McClain
(602) 722-7872
Gerald Klug
(415) 705-2155,
(FTS) 465-2199
John McClain
(602) 722-7872
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
O
»«
oo
REGION IX (Continued)
California
State Water Resources Control Board
Division of Clean Water Programs
P.O. Box 944212
Sacramento, CA 94224-2120
Hawaii
Construction Grants Program
Hawaii State Department of Health
5 Water Front Plaza, Suite 250
500 Alamona Blvd.
Honolulu, HI 96813
Nevada
Nevada Department of Environmental
Protection - Construction Grants
Capitol Complex
123 W. Nye Lane
Carson City, NV 89710
David Meza
(916) 739-4315
Dennis Tulang
(808) 543-8288
James Williams
(702) 687-5870
Archie Mathews
(916) 322-4567
Dennis Tulang
(808) 543-8288
James Williams
(702) 687-5870
Donald Proctor
(916) 744-4150
Dennis Tulang
(808) 543-8288
Julian Bielawski
(702) 687-467(1
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION X
U.S. EPA Water Management Division
1200 Sixth Avenue
Seattle, WA 98101
Alaska
Alaska Department of Environmental
Conservation
O Division of Water Programs
S P-O. Box O
Juneau, AK 99811
Idaho
Idaho Department of Health and Welfare
Division of Environment
State House
Boise, ID 83720
Oregon
Oregon Department of Environmental Quality
811 SW6th Street
Portland, OR 97204
Bryan Yim
(206) 442-8575
(FTS) 399-8575
Richard Marcum
(907) 465-2610
Bob Braun
(208) 334-5860
Francis Dzata
(503) 229-5370
Dick Hetherington
(206) 442-1941
(FTS) 399-1941
Stan Hungerford
(907) 465-2610
Susan Martin
(208) 334-5855
Richard Nichols
(503) 229-5324
Clarence Orimon
(206) 442-2887
(FTS) 399-2887
Judy Urquart
(907) 465-2673
Linda Taylor
(907) 465-2610
Veronica Shawcroft
(208) 888-1740
Thomas Gonzalez
(503) 928-2361
-------
APPENDIX C (Continued)
U.S. EPA REGION
TECHNOLOGY
CONTACT
SLUDGE CONTACT
O&M CONTACT
REGION X (Continued)
Washington
Department of Ecology
Office of Water Programs
Olympia, WA 98504
Al Newman
(206) 459-6089
Jim Knudson
(206) 459-6597
Carol Jones
(206) 438-7044
Stan Ciuba
(206) 438-7042
O
-------
APPENDIX D
EPA REGIONAL WASTEWATER TREATMENT OUTREACH COORDINATORS
-------
APPENDIX D
EPA REGIONAL WASTEWATER TREATMENT
OUTREACH COORDINATORS
I. Mark Malone (WMT-2113) H.
Water Management Division
U.S. EPA Region I
JFK Federal Building, Room 2113
Boston, MA 02203
(617) 565-3492
(FTS) 835-3492
II. Andrea Coats (for New York) U.
(212) 264-2929
(FTS) 264-8349
III. Bob Runowski (3WM23) IV.
Water Management Division
U.S. EPA Region III
841 Chestnut Street
Philadelphia, PA 19107
(215) 597-6526
(FTS) 597-6526
V. Al Krause VI.
Water Management Division
U.S. EPA Region V
230 S. Dearborn Street
Chicago, IL 60604
(312) 886-0246
(FTS) 886-0246
VII. Kelly Beard VIII.
Water Mangement Division
U.S. EPA Region VII
726 Minnesota Avenue
Kansas City, KS 66101
(913) 551-7217
(FTS) 551-7217
IX. Elizabeth Borowiec (W2-2) X.
Water Management Division
U.S. EPA Region IX
1235 Mission St.
San Francisco, CA 94103
(415) 705-2136
(FTS) 465-2136
Ponce Tidwell (for New Jersey)
Water Management Division
U.S. EPA Region H
26 Federal Plaza
New York, NY 10278
(212) 264-5673
(FTS) 264-5673
Yolanda Guess (for Caribbean)
(212) 264-8968
(FTS) 264-8968
Roger De Shane
Water Management Division
U.S. EPA Region IV
345 Courtland Street, N.E.
Atlanta, GA 30365
(404) 347-3633
(FTS) 257-3633
Gene Wossum
Water Management Division
U.S. EPA Region VI
1445 Ross Avenue, #1200
Dallas, TX 75202
(214) 655-7130
(FTS) 255-7130
Harold Thompson
Water Management Division
U.S. EPA Region VIII
999 18th Street, #500
Denver, CO 80202
(303) 293-1560
(FTS) 330-1560
Bryan Yim
Water Management Division
U.S. EPA Region X
1200 6th Avenue
Seattle, WA 98101
(206) 442-8575
(FTS) 399-8575
D-l
-------
APPENDIX E
SUMMARY OF INNOVATIVE AND ALTERNATIVE
TECHNOLOGY PROJECTS BY STATE
-------
SUMMARY OF INNOVATIVE TECHNOLOGY PROJECTS
EPA
REGION STATE
1 Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
III Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
" Ohio
Wisconsin
VI Arkansas
Lousiana
New Me xi co
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIM Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Territories
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washington v
TOTAL
Aeration
Counter Current Aeration
1
1
5
1
1
1
5
1
7
1
24
Draft Tube Aeration
1
1
3
1
2
1
2
4
2
1
1
1
20
Fine Bubble Diffusers
1
1
2
1
2
2
2
11
Aero-mod System
1
1
3
5
Ȥ
O'=
>.cd
11
?i
ll
4
2
6
Other Aeration
1
1
1
1
1
1
1
1
2
2
12
Clarification
Flocculating Clanfiers
2
1
1
4
Integral Glanders
2
1
1
4
Intrachannel Clanfiers
1
1
2
3
4
7
1
1
2
2
1
1
3
1
4
1
2
1
1
4
2
1
46
Swirl Concentrators
1
1
1
1
3
1
8
Other Clarification
1
1
1
1
1
1
1
2
1
10
Collection
Small Diameter Gravity
Sewers
1
1
1
4
1
8
Other Collection Systems
i
-
2
1
1
5
E-l
-------
SUMMARY OF INNOVATIVE TECHNOLOGY PROJECTS (cont'd)
EPA
REGION STATE
1 Connection
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
III Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
Ohio
Wisconsin
VI Arkansas
Lousiana
New Mexico
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIII Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Territories
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washingt«n
TOTAL
Disinfection
Ultraviolet Disinfection
2
1
1
1
1
4
3
1
1
5
3
1
1
4
4
1
3
1
1
4
4
1
1
49
Other Disinfection
2
1
1
1
1
1
1
1
1
1
11
isoosal
of
Effluent
Other Disposal of Effluent
2
1
1
1
5
Energy
Conservation
and Recovery
I
CO
i
5
3
1
1
1
1
1
i
i
1
1
1
10
Other Energy Conservation
and Recovery
1
1
4
1
3
1
1
1
1
3
1
1
1
20
Filtration
Biological Aerated Filters
1
1
1
3
Microscreens
1
1
1
1
1
1
6
Other Filtration
1
2
2
1
1
2
1
1
1
1
2
2
3
20
Lagoons
Aquaculture
1
2
1
2
6
Hydrograph Controlled
Release Lagoons
3
5
2
8
1
2
1
1
1
1
25
Single Cell Lagoon
with Sand Filter
10
10
Other Lagoons
1
X*
2
1
2
1
1
1
1
1
1
1
1
14
E-2
-------
SUMMARY OF INNOVATIVE TECHNOLOGY PROJECTS (cont'd)
EPA
REGION STATE
1 Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
III Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
* Ohio
Wisconsin
VI Arkansas
Lousiana
New Mexico
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIII Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Territories
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washingtoo
TOTAL
Land
Application
of Effluent
Overland Flow
2
1
1
3
1
1
3
12
Other Land Application
of Effluent
1
1
1
1
1
1
1
1
1
1
1
1
1
1
14
Nitrifi-
cation
Other Nitrification
2
1
1
1
1
2
1
9
Nutrient Removal
Anoxic/oxic system (A/O)
1
1
1
1
1
1
6
Q.
5
1
1
2
1
1
5
Sequencing Batch Reactor
(SBR)
1
3
2
1
6
3
3
1
1
1
22
Other Nutrient Removal
2
1
1
1
2
1
1
2
1
1
13
Oxidation
Ditch
Barrier Wall Oxidation Ditch
3
1
4
Other Oxidation Ditch
1
3
2
6
1
5
2
1
3
1
2
1
1
5
2
1
1
1
1
1
41
Fixed Growth
Rotating Biological
Contactors (RBC's)
1
1
1
1
1
5
Trickling Filter/Solids Contact
1
2
1
1
1
1
1
2
1
1
12
Other Fixed Growth
\»
1
1
E-3
-------
SUMMARY OF INNOVATIVE TECHNOLOGY PROJECTS (cont'd)
EPA
REGION STATE
1 Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
Ml Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
Ohio
Wisconsin
VI Arkansas
Lousiana
New Mexico
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIII Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Territories
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washington
TOTAL
Sludge Technologies
Carver-Greenfield
1
2
3
Composting
2
11
1
1
3
6
1
14
2
2
2
2
1
1
2
4
5
1
1
62
Digestion
1
1
2
1
1
1
1
a
is
i
1
2
1
5
Vacuum Assisted Sludge
Drying Beds
1
1
1
1
2
1
1
1
1
1
1
1
1
1
15
Other Sludge Technologies
4
1
1
2
1
1
1
1
2
3
2
1
1
1
2
1
25
Onsite
Tech-
nologies
Other Onsite Technologies
1
1
1
3
Miscellaneous
Enclosed Impellor Screw Pump
1
1
2
4
Other Miscellaneous
2
1
1
1
1
1
1
1
1
2
1
1
A
1
2
1
i
1
24
Suspended
Growth
Powdered activated
Carbon/Regeneration
1
1
2
4
Other Suspended Growth
1
1
E-4
-------
SUMMARY OF ALTERNATIVE TECHNOLOGY PROJECTS
EPA
REGION STATE
1 Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
III Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
** Ohio
Wisconsin
VI Arkansas
Louisiana
New Me xi co
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIII Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Terntones
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washington ,
TOTAL
ONSITE TREATMENT
Septic Tank/Soil Absorption
System (Single Family)
4
1
3
3
1
1
2
4
1
2
10
1
1
2
36
Mound System
2
2
1
1
2
9
1
3
1
4
1
1
28
o
I
5
'5.
m
LLJ
2
2
Aerobic Unit
1
1
1
3
Sand Filter
1
5
1
4
2
12
2
1
2
15
2
1
1
1
1
2
3
56
Other Onsite Treatment
1
1
1
1
1
1
1
1
6
SOLIDS TREATMENT
Septage Treatment and Disposal
7
19
7
2
11
4
3
3
2
1
1
3
1
1
4
69
Land Spreading of POTW Sludge
1
12
1
2
2
4
6
9
2
4
13
3
4
5
5
44
20
16
24
35
13
2
1
10
29
24
20
34
5
2
9
11
1
2
1
1
1
6
4
1
389
Composting
1
6
5
1
1
5
2
1
2
1
5
3
3
1
2
1
2
4
1
1
1
2
1
1
1
1
55
Preapplication Treatment
3
1
1
i
17
3
3
3
9
1
2
8
2
3
1
2
3
1
64
90% Methane Recovery
from Anaerobic Digestion
4
2
16
2
3
5
2
3
3
4
2
6
1
13
5
4
6
6
3
1
1
7
6
5
1
3
1
2
4
1
1
3
5
3
1
3
5
2
145
Self- sustaining Incineration
(Heat Recovery and Utilization)
1
2
1
1
2
1
1
1
1
1
2
1
1
16
Other Sludge Treatment or Disposal
1
1
V.
2
3
1
1
1
5
1
1
1
2
8
2
1
1
2
1
2
37
E-5
-------
SUMMARY OF ALTERNATIVE TECHNOLOGY PROJECTS (cont'd)
EPA
REGION STATE
I Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
II New Jersey
New York
Puerto Rico
Virgin Islands
III Delaware
Washington DC
Maryland
Pennsylvania
Virginia
West Virginia
IV Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee
V Illinois
Indiana
Michigan
Minnesota
* Ohio
Wisconsin
VI Arkansas
Lousiana
New Mexico
Oklahoma
Texas
VII Iowa
Kansas
Missouri
Nebraska
VIII Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
IX Arizona
California
Guam
Trust Territories
Hawaii
Nevada
N. Marianas Islands
X Alaska
Idaho
Oregon
Washington 4
TOTAL
TREATMENT/DISCHARGE SYSTEMS
Overland Flow
1
2
2
3
1
2
1
11
2
4
4
6
1
14
1
2
57
Rapid Infiltration Land
Treatment Systems
1
2
1
3
1
1
1
1
2
1
1
1
4
1
17
1
1
2
3
8
2
1
14
1
5
4
1
81
Slow Rate
Treatment Systems
1
1
1
5
5
1
2
20
18
2
2
21
9
6
3
1
14
15
1
1
5
2
6
31
11
2
16
25
5
2
8
6
1
3
2
12
20
2
6
9
6
3
312
Other Land Treatment Systems
1
2
1
1
1
1
2
1
1
1
2
14
Septic Tank/Soil Absorption
System (Multiple Families)
2
7
3
1
1
2
2
2
2
1
2
7
9
3
1
5
2
1
1
54
Preapplication Treatment
or Storage
1
4
2
4
3
13
15
1
9
2
2
5
16
10
3
9
1
3
2
1
25
5
1
10
9
4
160
Total Containment Ponds
1
29
1
27
32
5
17
7
3
1
1
1
4
1
1
2
133
Aquaculture/Wedands/
Marsh Systems
2
2
2
1
1
3
1
2
1
5
4
3
1
1
2
1
32
Aquifer Recharge
1
1
2
Direct Reuse
5
3
5
4
1
1
2
21
COLLECTION SYSTEMS
Pressure Sewers, Septic Tank
Effluent Pump (STEP)
1
3
2
6
3
6
1
2
2
1
1
5
4
3
6
3
2
1
1
3
2
6
3
1
1
7
1
2
5
3
87
Small Diameter Gravity Sewers
1
1
16
1
3
13
2
5
3
1
5
1
1
2
10
21
14
2
7
2
4
2
1
1
1
15
14
2
1
4
2
1
2
4
2
167
Pressure Sewers,
Grinder Pump (GP)
i
i
3
2
16
V.
2
27
15
2
10
2
4
3
2
6
3
4
3
4
6
2
10
1
6
3
20
1
2
1
1
163
Vacuum Sewers
2
3
6
2
11
2
2
1
3
5
1
2
1
41
E-6
-------
APPENDIX F
X*
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES
BY STATE
-------
APPENDIX F
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES BY STATE
STATE
Alabama
Arizona
Arkansas
California
COMMUNITY
utttevme.
Leighton
PhU C:ampb^ll
Flagstaff
Ph^ljtifc'':-;:;:::.; ''.. . j .; ..:,;.:'
Paragould
Fallen L«4f Lake
Gustine
HaywatfdU;.:;... . .
Manila
$&VB$.&sGi£$.;,:.
Reediey
Saxi Lorenzo
SUB-
POTEN- JECT
M/R GRANT HAL OF
GRANT IN M/R LITIGA-
TECHNOLOGY AWARDED REVIEW PROJECT TION
IfttttefaMnrt ciKUuw *', *
Intrachannel clarifiers X
Intrachannel 6la:rt£le£s s ^ _ Xv -^ ^ v , *
Combined chlorination/clarification X
Aquaculture X
^JjlptltMltt ^*O 1 1 ttttt^1! tifYl ffV^t^^tll % ^f ' ' ' -. -. ^ . ' v
Aquaculture X
Community leach field X
Vacttua- assisted sludge dsrytTJg beds \ , ; X , ^ -- -' , * , - \
Rapid infiltration X
Pressure tea
-------
Massachusetts
APPENDIX F (Continued)
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES BY STATE
STATE
Illinois
Indiana
Kansas
Kentucky
Maine
COMMUNITY
Hanover
Portage
Bonner Springs '.
Dodge City
Berea
Elkton
Fresque I $10
Sabattus
TECHNOLOGY
Sand filters
Jfowdfcced aefclvatod carbon muttroaftt
(PACT)
Vacuum-assisted sludge drying beds
Intfachannel clarifiers . -
Odor control
Intrachannel clarififr . . .
Side channel clarifier
W dl* inaction . :..::
UV disinfection
M/R GRANT
GRANT IN
AWARDED REVIEW
X
X
-- ;:*..: ,.' r. "" ' x.
x.,
X
-. . :-.. X ,-,,,. . . V
X
SUB-
POTEN- JECT
TIAL OF
M/R LITIGA-
PROJECT TION
X
'" x ' """
j'^.S--1*^.
..,..,::, ,:,,/,::^..;.;.. ,,
Fall River
Southbridge
Way land
Westboro
Williams town
Self-sustaining incineration
Sludge composting
Septage treatment ;
Sludge composting
Grinder pumps/pressure sewers
X
X
X
X
Michigan
Ionia
Rotating biological contactors
X
-------
T]
APPENDIX F (Continued)
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES BY STATE
STATE
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Jersey
New Mexico
New York
North Carolina
COMMUNITY
Moor ahead '
Northfield
Sotth KoocMehing
Pine River
Rochester ;
Newton
Excelsior Springs
Gallatin
Littlfc Blue
Valley
Bozeman
Scotts Bluff
Henderson
Indite Village
Stafford
Santa Fe
Lawrence
Plattsburgh
Washington
Starr
M/R GRANT
GRANT IN
TECHNOLOGY AWARDED REVIEW
Active o??one disinfection '.''' X
UV disinfection X
UV tflsinfoetlwi X
Sludge composting and rotatating
biological contactors
Biological phosphorus removal X
Overland flow
Overland flow ! . X
Intrachannel clarifiers X
.LllCrciClRWjlJ!ls^ *-' {*Xaj)t il* X-OIr 8 . . . '
'' . ' j ..'. .'.';. : .
Rapid infiltration X
Hicroscreetj ponds :. X
Rapid infiltration basins
tfetltffi** X
Vacuum collection system controllers
Draft tube aerators; X .
Community mound systems X
In-vessel composting X
Draft tube aerators X
Draft tube aerators X
SUB-
POTEN- JECT
TIAL OF
M/R LITIGA-
PROJECT TION
X
X
X
X
X
-------
Tl
Rhode Island
South Carolina
South Dakota
APPENDIX F (Continued)
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES BY STATE
STATE
North Dakota
Ohio
Oregon
COMMUNITY
Burlington
Greajisboto
Greenville
Henderson
Pilot Mountain
&$&*v
Buchanan
Chu jxjhjflfc: ' Ffcr r y . <::. '' .""
Clifford
A&ron
Bedford Heights
Clyde
Ironton
Lake County
North Olms tead
South Point
6t*as
Community mound systems
In-vessel compoating , . *
Powdered activated carbon treatment
(PACT)
Intrachannel clarifies* . ,-...
UV disinfection
Composting . ,
Powdered activated carbon treatment
Rotating biological contactors
Conawntty l^wh fl«14>% ' is^ ? :
w : $^ S f ^
Recirculating sand filter
SUB-
POTEN- JECT
M/R GRANT TIAL OF
3RANT IN M/R LJTIGA-
\WARDED REVIEW PROJECT TION
X
^
X
X fct
X
x _^ ^^_ s { 4 ^
"x
X
X
$.
X
& , , ,, ^ <<',*.<>
x' ' '*'
x t
X
x
X , , - s "\ ' ,- * ~ »C " ' ^S
X '
Cranston
Draft tube aerators
X
Mina Lake
Community mound systems
*tVi 4*- f*1 'A jK^t ^-' wi 4 **ifai^Vt iii^'' i '*jVA>kV%rf*.:
X
x
-------
APPENDIX F (Continued)
CURRENT STATUS OF MODIFICATION/REPLACEMENT (M/R) GRANT CANDIDATES BY STATE
STATE COMMUNITY
Polioc*
Tennessee ciaibome Co.
Memphis
Texas El Paso
Lave Hand
71 Virginia Buena Vista
Washington Black Diamond
Elbe
West Virginia crab Orchard*
MmiArthur :
Wisconsin Cambellsport
Hayward
Wittenberg
TECHNOLOGY
Rat>id infiltration fivstetn '
Counter current aeration
Biof Utei-a :'1;;> ;-': ;v,; : ' . . . y.
Draft tube aerators
Aeration/oxidation .ponds
Vacuum- assisted sludge drying beds
Wetlands .!:.. . ... .
Community mound systems
, ., ,.'...,:;. ','..-'.'. 'I',. /;'' . "" '.'.-'.,'.-".' :. .' '.'.. *.
; . : ; ; ; _. - . ,....................,... ....... _ ...,.,_.. i ;;'; ;;.. " / ; ;
Rapid infiltration
Rapid infiltration i
Rapid infiltration
POTEN-
M/R GRANT TIAL
GRANT IN M/R
AWARDED REVIEW PROJECT
-., , -
'. . ' . . ,.*»:..
X
X
X
X
X
x . . ..
X
:': ' .-':"" '"'' "': -':':'" "-'':v:.'
X
X
SUB-
JECT
OF
LITIGA-
TION
:;:;7X''"'
X
f
Rofcacing biological contactots
X
-------
APPENDIX G
LIST OF WASTEWATER TECHNOLOGY PUBLICATIONS
-------
APPENDIX G
LIST OF WASTEWATER TECHNOLOGY PUBLICATIONS
TITLE
Innovative and Alternative (I/A) Technology: Wastewater
Treatment to Improve Water Quality and Reduce Cost
\
Innovations in Sludge Drying Beds: A Practical Technology
Intermittent Sand Filtration
Intrachannel Clarification: A Project Assessment
In-Vessel Composting
Land Application of Sludge: A Viable Alternative
Land Treatment Silviculture: A Practical Approach
Large Soil Absorption Systems: Design Suggestions for Success
DOCUMENT
ORDER
SOURCE
Current Wastewater Technology Foldouts
Alternative Wastewater Collections Systems: Practical Approaches
Aquaculture: An Alternative Wastewater Treatment Approach
The Biological Aerated Filter: A Promising Biological Process
Biological Phosphorous Removal: Problems and Remedies
Composting: A Viable Method of Resource Recovery
Counter-Current Aeration: A Promising Process Modification
Disinfection with Ultraviolet Light
Hydrograph Controlled Release Lagoons: A Promising Modification
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
1,2,3,4
G-l
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Current Wastewater Technology Foldouts (Continued)
Less Costly Wastewater Treatment for Your Town 1,2,3,4
Methane Recovery: An Energy Resource 1,2,3,4
Natural Systems for Wastewater Treatment in Cold Climates 1,2,3,4
Operation of Conventional WWTP in Cold Weather 1,2,3,4*-
Overland Row An Update: New Information Improves Reliability 1,2,3,4
Planning Wastewater Facilities for Small Communities 1,2,3,4
Rapid Infiltration: Plan, Design, and Construct for Success 1,2,3,4
Rotating Biological Contactors 1,2,3,4
Sequencing Batch Reactors: A Project Assessment 1,2,3,4
Side-Streams in Advance Waste Treatment Plants: Problems and
Remedies 1,2,3,4
Small Wastewater Systems: Alternative Systems for Communities
and Rural Areas 1,2,3,4
Vacuum-Assisted Sludge Dewatering Beds: An Alternative Approach 1,2,3,4
Vacuum-Assisted Sludge Drying (Update) 1,2,3,4
Wastewater Stabilization Ponds: An Update on Pathogen Removal 1,2,3,4
Water Reuse Via Dual Distribution Systems 1,2,3,4
Wetlands Treatment: A Practical Approach 1,2,3,4
G-2
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Wastewater Research Reports
Alternative On-Site Wastewater Treatment and Disposal Systems on
Severely Limited Sites; EPA/600/2-86/116; PB87-140992/AS 1,5,6
Alternative Sewer Studies; EPA/600/2-85/133; PB86-131224/AS 1,5,6
Alternative Sewer Systems in the United States; EPA/600/D-84/095;
PB84-177815/AS 1,5,6
Autothermal Thermophilic Aerobic Digestion in the Federal Republic
of Germany; EPA/600/D-85/194; PB85-245322/AS 1,5,6
Biological Phosphorus Removal - Technology Evaluation;
EPA/600/J-86/198; PB87-152559 1,5,6
Characterization of Soil Disposal System Leachates; EPA/600/2-84/
101; PB84-196229/AS 1,5,6
Costs of Air Pollution Abatement Systems for Sewage Sludge
Incinerators; EPA/600/2-86/102; PB87-117743/AS 1,5,6
X
Control of Pathogens in Municipal Wastewater Sludge
EPA 625/10-89/016 5
Design Manual Municipal Wastewater Stabilization Ponds;
EPA/625/1-83-015 1,5,6
Determination of Toxic Chemicals in Effluent from Household Septic
Tanks; EPA/600/2-85/050; PB85-196798 1,5,6
Emerging Technology Assessment of Phostrip, A/O and Bardenpho
Process for Biological Phosphorus Removal; EPA/600/2-85/008;
PB85-165744/AS 1,5,6
Evaluation of Anaerobic, Expanded-Bed Contactors for Municipal
Wastewater Treatment; EPA/600/D-86/120; PB86-210648/AS 1,5,6
G-3
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Wastewater Research Reports (Continued)
Evaluation of Color Infrared Aerial Surveys of Wastewater Soil
Absorption Systems; EPA/600/2-85/039; PB85-189074/AS 1,5,6
Fine Pore Aeration Systems; EPA 625/1-89/023 5
Constructed Wetlands and Aquatic Plant Systems for Municipal
Wastewater Treatment; EPA 625/1-88/022 5
Forecasting On-Site Soil Absorption System Failure Rates;
EPA/600/2-86/060; PB86-216744/AS 1,5,6
Full-Scale Studies of the Trickling Filter/Solids Contact
Process; EPA/600/J-86/271; PB87-168134/AS 1,5,6
Handbook Estimating Sludge Management Costs; EPA/625/6-85/010;
PB86-124542/AS 1,5,6
Handbook Septage Treatment and Disposal; EPA/625/6-84-009 1,5,6
Implernention of Sequencing Batch Reactors for Municipal Treatment;
EPA/600/D-84/022; PB84-130400/AS 1,5,6
In-Vessel Composting of Municipal Wastewater Sludge;
EPA 625/8-89/016 5
Innovative and Alternative Technology Assessment Manual;
EPA/430/9-78/009; (MCD-53) 1,3,6
Land Application of Municipal Sludge; EPA/625/1-83/016 1,5,6
Large Soil Absorption Systems for Wastewaters from Multiple
Home Developments; EPA/600/2-86/023; PB86-164084/AS 1,5
Municipal Sludge Composting Technology Evaluation; EPA/600/J-86/139;
PB87-103560/AS 1,5,6
G-4
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Wastewater Research Reports (Continued)
Odor and Corrosion Control in Sanitary Sewerage Systems and
Treatment Plants; EPA 625/1-85/018 5
Process Design Manual for Land Application of Municipal Sludge;
EPA/625/1-83-016 1,5,6
Process Design Manual for Land Treatment of Municipal Wastewater;
EPA/625/1-81-013 and Supplement; EPA/625/l-81-013a 1,5,6
Small Diameter Gravity Sewers: An Alternative Wastewater
Collection Method for Unsewered Communities; EPA/600/2-86/0270;
PB86-173622/AS 1,5
Start-up and Operation of Chemical Process Technologies in the
Municipal Sector - the Carver-Greenfield Process for Sludge
Drying; EPA 430/09-89/007; PB90-161902/AS; IRC 137U 1,6
Status of Porous Biomass Support Systems for Wastewater Treatment:
An Innovative/Alternative Technology Assessment; EPA/600/2-86/019;
PB85-156965/AS 1,5
Summary Report: Fine Pore (Fine Bubble) Aeration Systems;
EPA/625/8-85/010 1,5,6
Technology Assessment of Aquaculture Systems for Municipal
Wastewater Treatment; EPA/600/2-84/145; PB84-246347/AS 1,5,6
Technology Assessment of Sequencing Batch Reactors; EPA/600/2-85/007;
PB85-167245/AS 1,5,6
Technology Assessment for Wetlands for Municipal Wastewater
Treatment; EPA/600/2-84/154; PB85-106896/AS 1,5,6
G-5
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Wastewater Research Reports (Continued)
Technology Evaluation of Sequencing Batch Reactors; EPA/600/J-85/166
Technology Evaluation of the Dual Digestion System; EPA/600/J-86/150;
PB87-116802/AS
The Lubbock Land Treatment System Research and Demonstration
Project: Volume IV, Lubbock Infection Surveillance Study;
EPA/600/2-86/027D; PB86-173622/AS
Toxic and Priority Organics in Municipal Sludge Land Treatment
Systems; EPA/600/2-86/010; PB86-150208/AS
Trickling Filter/Solids Contact Process: Full-Scale Studies;
EPA/600/2-86/046; PB86-183100/AS
Wastewater Treatment Plant Instrumentation Handbook; EPA/600/
8-85/026; PB86-108636/AS
1,5,6
1,5,6
1,5
1,5
1,5,6
1,5,6
OtheP Wastewater Publications
A Water and Wastewater Manager's Guide for Staying Financially
Healthy; EPA/430-09-89-004
Building Support for Increasing User Fees; EPA/430/09-89-006
Design Manual: On-Site Wastewater Treatment and Disposal Systems;
EPA/625/1-80-012
Is Your Proposed Wastewater Project Too Costly? Options for Small
Communities
It's Your Choice - A Wastewater Treatment Handbook for the
Local Official
1,2,3
1,2,3
13,5
1,2,3
1,2
G-6
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Other Wastewater Publications (Continued)
Looking at User Charges - A State Survey and Report 1,2,3
Management of On-Site and Small Community Wastewater Systems;
EPA/600/8-82-009 1,2,3,5
Planning Wastewater Management Facilities for Small Communities;
EPA/600/8-80-030 1,2,3,5
Touching All the Bases: A Financial Handbook for Your Wastewater
Treatment Project 1,2
Value Engineering for Small Communities; EPA 430/09-87/011;
PB88-184858/AS; IRC 122U 1,6
Wastewater Technology Videotapes
Sand Filters (9 minutes) 1,2
Small Diameter Effluent Sewers (11 minutes) 1,2
\
Planning Wastewater Facilities for Small Communities (15 minutes) 1,2
Upgrading Small Community Wastewater Treatment (20 minutes) 1,2
G-7
-------
APPENDIX G (continued)
TITLE
DOCUMENT
ORDER
SOURCE
Document Order Sources:
(1) Environmental Quality Instructional
Resources Center (IRC)
The Ohio State University
1200 Chambers Road - Room 310
Columbus, OH 43212
314-292-6717
(2) National Small Rows Clearinghouse
258 Stewart Street
Morgantown, WV 26506
1-800-624-8301
(3) EPA-OMPC-MFD (WH-595)
401 M Street, S.W.
Washington, DC 20460
(4) EPA Regional Offices
For telephone numbers, see
Appendix D
(5) EPA Center for Environmental
Research Information (CERI)
26 West Martin Luther King Drive
Cincinnati, OH 45268
513-569-7562
(6) National Technical Information
Service (NTIS)
5285 Port Royal Road
Springfield, VA 22161
703-487-4650
Note: Depending upon ordering source, there may be a charge for some
documents.
G-8
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