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Executive Summary

This report is meant to serve as a resource on nutrient removal technologies for

the Fox River Watershed in Illinois. The technologies discussed are for phosphorus

removal, nitrogen removal, and nitrogen and phosphorus removal, so that facilities will

keep in mind the feasibility of adding nitrogen. Currently, the Fox River is undergoing a

study to determine potential reduction in future phosphorus loadings to the river from

various sources. As a first step, phosphorus limits of 1.0 ���

� likely will be given to

Water Resource Recovery Facilities (WRRF) in the watershed and a provision to study

the feasibility of reaching a limit of 0.5 ���

�. Additionally, current water quality modeling

includes a scenario were WRRF effluents are reduced to 0.1 ���

�. Several technologies

exist to meet these effluent limits both chemically and biologically, but one technology is

not the always the best. The characteristics of each WRRF must be used to determine

the best process for that plant because each facility has: different influent fractions

(nitrogen, BOD, and phosphorus), different hydraulic profiles, different land available to

expand the WRRF, different projected growth, and different existing process. These

differences mean that a detailed study is necessary to choose the best process to meet

future phosphorus limits. Also, the cost estimates included for meeting phosphorus

removal standards are a rough guideline that can be used until an individual plant study

has been completed. The primary sources for this report are: Nutrient Removal by

WEF, Nutrient Control Design Manual (EPA/600/R-10/100), Sustainable Technology

For Achieving Very Low Nitrogen and Phosphorus Effluent Levels (WERF/IWA), and

Biological Nutrient Removal Processes and Costs (EPA-823-R-07-002).

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Table of Contents

1.0 Introduction ........................................................................................................ 6

1.1 Purpose/Context ................................................................................................ 6

1.2 Organization of the Report ................................................................................. 7

2.0 Nutrient Removal Processes .............................................................................. 8

2.0.1 Biological Nitrogen Removal Processes ...................................................... 8

2.0.2 Biological Phosphorus Removal Processes .............................................. 10

2.1 Chemical Nutrient Removal Processes ............................................................ 11

2.1.1 Struvite ...................................................................................................... 11

3.0 Technology Review .......................................................................................... 13

3.1 Description of Process Flow Diagrams ............................................................ 13

3.2 Nitrogen Removal Systems .............................................................................. 13

3.2.1 Step Feed .................................................................................................. 13

3.2.2 MLE (modified Ludzack-Ettinger) .............................................................. 14

3.2.3 Denitrification Filters .................................................................................. 15

3.2.4 Bardenpho (four-stage).............................................................................. 15

3.3 Phosphorus Removal Technologies ................................................................. 16

3.3.1 Phoredox (A/O) .......................................................................................... 16

3.3.2 Chemical Addition ...................................................................................... 16

3.3.3 Filtration ..................................................................................................... 17

3.3.4 Phostrip ..................................................................................................... 18

3.4 Combined Nitrogen and Phosphorus Removal Systems ................................. 18

3.4.1 Three-stage Phoredox (A2O) .................................................................... 18

3.4.2 Modified (five Stage) Bardenpho ............................................................... 19

3.4.3 University of Cape Town (UCT) ................................................................. 19

3.4.4 Virginia Initiative Process (VIP) ................................................................. 20

3.4.5 Orange Water and Sewer Authority (OWASA) .......................................... 20

3.4.6 Sequencing Batch Reactors (SBR) ........................................................... 21

3.4.7 Surface Aerated Plants .............................................................................. 21

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3.4.8 Pearl® Process .......................................................................................... 22

3.4.9 Membrane Bioreactors (MBRs) ................................................................. 23

3.5 Developing Technologies ................................................................................. 23

3.5.1 Simultaneous Nitrification and Denitrification (SND) .................................. 24

3.5.2 SHARON ................................................................................................... 24

3.5.3 Anammox .................................................................................................. 24

3.5.4 Algae Reactors .......................................................................................... 25

3.6 Summary of Treatment Technologies .............................................................. 26

4.0 Considerations ................................................................................................. 27

5.0 Cost Ranges .................................................................................................... 29

5.1 Qualifiers .......................................................................................................... 29

5.2 Cost Information ............................................................................................... 29

6.0 Conclusions...................................................................................................... 37

6.0 References: ...................................................................................................... 38

7.0 Appendix 1 NPDES Permit Information .............................................................. 1

7.1 Appendix 2 Sample Cost Calculation ................................................................. 1

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Glossary

Anammox Anaerobic Ammonium Oxidation

AOB Ammonia Oxidizing Bacteria

BNR Biological Nutrient Removal

BPR Biological Phosphorus Removal

DEMON® Deammonification

DO Dissolved Oxygen

EBPR Enhanced Biological Phosphorus Removal

ENR CCI Engineer News-Record Construction Cost Index

FRIP Fox River Implementation Plan

HAc Acetic Acid or Vinegar

IFAS Integrated Fixed Film Activated Sludge

MBBR Moving Bed Biofilm Reactor

MBR Membrane Bioreactor

MLSS Mixed Liquor Suspended Solids

NOB Nitrite Oxidizing Bacteria

O&M Operations and Maintenance

PHB Poly-Hydroxyl-Butyrate

RAS Return Activated Sludge

SHARON Single Reactor System for High Activity Ammonium Removal over

Nitrite

SND Simultaneous Nitrification and Denitrification

SRT Solids Retention Time

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Treatment Levels

Treatment

Level

Effluent

Total

Nitrogen

(TN) (�� �

)

Effluent

Total

Phosphorus

(TP), (��

)

1 8 1

2 5 0.5

3 3 0.1

Table 1 Treatment Levels1 pg85adapted

*Modifier ‘N’ or ‘P’ are used in the text to denote limits for nitrogen or phosphorus only.

For example, Level 2P is only a phosphorus limit of 0.5 ��

(total phosphorus), with no

nitrogen limit.1

TKN Total Kjeldahl Nitrogen

VFA Volatile Fatty Acid

WAS Waste Activated Sludge

WRRF Water Resource Recovery Facility

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1.0 Introduction

1.1 Purpose/Context

This report on current technologies and cost of biological nutrient removal (BNR)

was created, for the Fox River Implementation Plan (FRIP) Project. The FRIP “will be

the roadmap for watershed decision makers that will define the reduction in pollutant

discharges needed and in-stream projects to be executed that, when implemented, will

improve water quality of the Fox River.“9 The goals of the FRIP are meant to replace a

traditional TMDL plan by using recommendations from local stakeholders.9 Most of the

Fox River’s watershed is in the developed area around Milwaukee and Chicago.

Therefore, detailed stream models have been or will be developed to determine the total

nutrient loading reductions from both point and non-point sources. The main goal is to

increase dissolved oxygen in the Fox River by reducing algal impairments. In order to

reduce algae growth, phosphorus and possibly nitrogen loading to the Fox River will

need to be reduced. Currently, WRRFs discharging to the Fox River watershed are

expected to be able to meet a 1 ��

monthly limit within 5 years of receiving a new

NPDES permit. In the new permit, special conditions are presently asking WRRF to

perform a study to determine the technical and financial feasibility of meeting a

seasonal 0.5 ��

monthly limit. Many plants throughout the US in environmentally

sensitive areas have been meeting effluent limits of 1.0 ��

since the 1980s.2 pg1-2

Subsequently, the costs associated with phosphorus removal to 1.0 ��

are known.

For the FRIP model, the lowest effluent concentration of phosphorus being

examined is below 0.10 ��

. Currently, several plants in the US have seasonal

phosphorus limits below 0.10 ��

, but the cost of treating WRRF effluent to that

standard are highly variable due to the different makeup of various plant’s influent.

Nevertheless, treatment processes exist to reach 0.10 ��

for most municipal treatment

plants.3 pg4-5

The purpose of this report is to be a resource to give WRRFs in the Fox River

watershed an understanding of what treatment technologies are available to meet

anticipated limits. Many different processes can allow a plant to reach the nutrient

limits, so the processes described below are best thought of as a toolbox. Each

process can be placed in part, full, or in combination with other processes in a plant

currently performing secondary treatment. Moreover, when designing a plant to meet a

1.0 ��

limit, the plant should ideally be designed with the flexibility to reach lower

nutrient limits without substantial redesign of existing processes. This report includes a

range of technologies spanning from mature processes to cutting edge ideas. The

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technologies discussed include a range of process technologies that are at different

levels of development. Some processes have had decades of experience operating in

a full-scale WRRF while others are promising technologies entering pilot scale testing.

1.2 Organization of the Report

This report consists of 6 chapters including this introduction, chapter 1, and two

appendices.

• Chapter 2.0 is a summary of the basic chemical and biological process of nutrient

removal.

• Chapter 3.0 gives a summary of various nutrient removal technologies to meet

various nutrient limits.

• Chapter 4.0 provides rough cost information for BNR facilities.

• Chapter 5 summarizes likely technologies for Fox River WRRFs.

• Chapter 6 provides the report’s references.

• Appendix 1 gives a list of WRRF based upon their limits and rated capacity.

• Appendix 2 contains a sample cost calculation.

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2.0 Nutrient Removal Processes

Nutrient removal technologies can be broadly grouped as either biological or

physical/chemical processes.1 pg60,73 For phosphorus removal, chemical processes are

typically more straight forward to operate and often more reliable than biological

processes.1 pg74,78 Additionally, enhanced biological phosphorus removal (EBPR) can be

a “relatively inexpensive and environmentally sustainable option for phosphorus

removal.”1 pg78

2.0.1 Biological Nitrogen Removal Processes

All living organisms are composed partially of nitrogen. The typical

microorganisms in an activated sludge plant are approximately 12% nitrogen.10 pg137

Therefore, all secondary treatment processes remove nitrogen with the waste activated

sludge (WAS). Nitrogen enters the WRRF in several forms.

Figure 1 Total Nitrogen Fractions4 pg4

The dominant form of nitrogen entering a WRRF is generally ammonia formed

from the hydrolysis of urea.2 pg2-2 Generally, nitrate and nitrite are consumed

anaerobically in sewers, so a plant influent TKN equals the influent total nitrogen. TKN

is the ammonia and organic nitrogen that enters a plant. The organic nitrogen can be

further classified as either particulate or soluble and biodegradable versus

unbiodegradable as shown in the figure above. In general, particulate TKN is removed

by clarifiers and if necessary effluent filters. Unbiodegradable soluble TKN typically

passes through a WRRF and can be a major obstacle to meeting Total Nitrogen limits

below 3���

. Most biodegradable soluble TKN is broken down into ammonia and then

nitrified. Nitrification is an aerobic process that converts ammonia to nitrite and then to

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nitrate using carbon dioxide, alkalinity, and oxygen. The process is shown in the

equations below.2 pg4-6

Equation 1 Ammonia Oxidation2 pg4-6

Equation 2 Nitrate Oxidation2 pg4-6

The nitrate produced by nitrification is removed via the denitrification process.

Denitrification occurs in anoxic conditions where nitrate is present but in the absence of

oxygen. Microorganisms receive more energy if they use oxygen instead of nitrate to

oxidize BOD, so bacteria will not use nitrate, unless oxygen is unavailable.

Microorganisms use nitrate as replacement of oxygen, and they consume BOD with the

nitrate. The bacteria convert the BOD to carbon dioxide, and the nitrate becomes

nitrogen gas, which diffuses into the atmosphere. Also, denitrification uses hydrogen

ions, so alkalinity is produced by this process helping to offset the alkalinity consumed

by nitrification. The equation below shows the process of denitrification using methanol

as the BOD source.2 pg4-20

Equation 3 Denitrification2 pg4-20

The anammox process is a different path for the removal of nitrogen. Ammonia

nitrite, and alkalinity are used to generate nitrogen gas and nitrate. The following

equation describes the anammox process.2 pg4-34

Equation 4 Anammox2 pg4-34

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2.0.2 Biological Phosphorus Removal Processes

Phosphorus is an essential nutrient for microbial growth. Microorganisms in WRRF

performing secondary treatment have a phosphorus content of about 2.7%.10 pg535 Most

secondary treatment facilities are wasting sludge, so a portion of the influent

phosphorus is already being removed in the WAS. This process is referred to as

biological phosphorus removal (BPR). BPR has an upper limit on the amount of

phosphorus that can be removed. The only method of increasing the amount of

phosphorus removed using BPR is to waste more sludge; this reduces the facility’s

SRT. If too much sludge is wasted, the SRT will drop low enough that nitrifiers or other

bacteria will be washed (wasted) out resulting in process failures. Therefore, a limit

exists on the amount of phosphorus that can be removed using BPR. In addition, the

costs of sludge disposal could be high enough that increasing the amount of sludge

wasted might not be economical.

One method of increasing the phosphorus concentration in WAS is to grow Poly-

phosphate accumulation organisms (PAO). If activated sludge is cycled through

anaerobic tanks containing volatile fatty acids (VFA), including acetic acid or vinegar,

then passed through an aerobic tank, PAOs will take up phosphorus by the end of the

aerobic zones increasing the phosphorus content of the WAS.2 pg5-1,3 This process is

known as enhanced biological phosphorus removal (EBPR). PAOs take up

polyphosphate in the aerobic zones to store energy. In the anaerobic zone, the PAOs

take up VFAs, HAc, or vinegar using the stored energy in polyphosphate. In bacteria,

the vinegar is stored as PHB or poly-hydroxyl-butyrate. When VFAs are taken up by the

PAOs, phosphorus is released simultaneously. A plant with functioning EBPR should

always have soluble phosphorus concentrations above the plant influent phosphorus

concentration in its anaerobic tank. The PAOs consume the PHB in the aerobic tank

using oxygen similar to other activated sludge bacteria. A portion, of the energy

released when PHB is consumed, is used to store phosphorus as polyphosphate. The

process is shown in figure below:

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Figure 2 Enhanced Biological Nutrient Removal2 pg5-1

2.1 Chemical Nutrient Removal Processes

Current IEPA design standards require EBPR processes to have a chemical

backup. Chemical backup systems are also good practice because they can be started

up quickly. EBPR can annually fail during certain periods.11, 1 pg78 Therefore, a chemical

backup should be included in any plant designed to use EBPR. The most common

chemicals used to remove phosphorus/phosphate are lime (CaO), alum (aluminum

sulfate or Al3+), and ferric (Fe3+). Typically, lime is only used to treat sidestreams

containing high levels of phosphorus. Lime effectively removes phosphorus at pHs

above 10.0. Therefore, the majority of the lime dose is used to raise the pH of the

wastewater rather than directly remove phosphates.1 pg76 The aluminum and ferric

families of chemicals are most commonly used in mainstream and tertiary chemical

phosphorus removal. Additionally, the dosage requirements of these chemicals

increases as the effluent phosphorus limit decreases.1 pg75 The dosage requirements

should be verified with lab testing and chemical pumps should be sized to meet various

chemical dosages.1 pg75 The dosage requirements are not constant for a WRRF,

because wastewater flows and concentration are highly variable.1 pg75 Alum is typically

the chemical of choice for WRRFs using UV disinfection because Ferric can reduce the

efficiency of UV disinfection. 2 pg9-2 One drawback to chemical phosphorus removal is

the generation of chemical sludge, which increases the amount of inert solids in a

activated sludge system, increases the amount of sludge to be disposed, and utilizes

clarifier capacity.

2.1.1 Struvite

Typically, struvite (magnesium ammonium phosphate) is typically seen at WRRF as

scale that forms in digester pipes and heat exchangers. As sludge breaks down in a

digester, phosphorus, magnesium, and ammonia are released and, react to form

struvite. One drawback of EBPR is that when PAOs take up negatively charged

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phosphorus molecules then positively charged magnesium is often taken up to keep the

cell neutral. Therefore, WAS from an EBPR plant will have a higher phosphate and

magnesium content increasing the chances of struvite formation. In some cases,

magnesium is added in order to purposely form struvite into pellets, rather than form

scale, which allows for the removal of phosphorus and ammonia.

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3.0 Technology Review

The process technologies discussed are both activated sludge configurations and

standalone processes that can be added to a plant performing secondary treatment. In

order to better compare various technologies, different levels of treatment are given for

both nitrogen and phosphorus removal in the table below.

Treatment

Level

Effluent

Total

Nitrogen

(TN) (���

)

Effluent

Total

Phosphorus

(TP), (��

)

1 8 1

2 5 0.5

3 3 0.1

Table 2 Treatment Levels1 pg85adapted

*Modifier ‘N’ or ‘P’ are used in the text to denote limits for nitrogen or phosphorus only.

For example, Level 2P is only a phosphorus limit of 0.5 ��

(total phosphorus), with no

nitrogen limit.1 3.1 Description of Process Flow Diagrams

The majority of the process flow diagrams were taken from WEF Manual of Practice

34, Nutrient Removal. In the diagrams, different types of tanks are shaded differently:

aerobic tanks and clarifiers are white, anoxic tanks are hatched, anaerobic tanks are

black, and filters and media reactors are dotted.

Aerobic Tank Clarifier Anoxic Tank Media Tank Anaerobic Tank

Filters

Figure 3 Tank Symbols

3.2 Nitrogen Removal Systems

3.2.1 Step Feed

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A step feed process for nitrogen removal involves the creation of a series of

paired anoxic and aerobic zones - see the figure below.3 pg4-14,15,16 Influent flow is split

to each anoxic zone. Return activated sludge (RAS) is sent to the first anoxic zone.

Each aerobic zone should be sized to convert most of the influent ammonia to nitrate.

Anoxic zones should be sized to convert most of the nitrate to nitrogen gas. This is

easier said than done. A WRRF has variable influent loadings, and tanks can only be

sized ideally for one set of nitrogen loadings. As a result, some step feed systems have

varying nitrogen removal due to changing influent nitrogen concentration and nitrogen

fractions.3 pg2-2 One advantage of step-feed systems is that they can be implemented

without adding large recycle lines. The major process changes involve the influent flow

being partially redirected and mixers added to select tanks. The step feed process can

reach 1N limits.3 pg2-14,ES-2

Figure 4 Process Flow Diagram for Step Feed Nitrogen Removal1 pg69

3.2.2 MLE (modified Ludzack-Ettinger)

The MLE process involves recycling RAS and a portion of an activated sludge

basin’s effluent back to the first (anoxic) tank.13 pg2-11 The recycled nitrate is converted to

nitrogen gas in the anoxic tank(s), and the influent ammonia is converted to nitrate in

the aerobic tanks. Higher recycle flow results in additional nitrogen removal, but the

process can never remove all nitrate from a plant’s effluent. It is not possible to recycle

100% of a plant’s effluent because a plant would not discharge any water and would be

a holding tank that would need to increase in size each day. Also, the recycle flow

dilutes the influent flow slowing down biological process in the activated sludge tanks,

and less nitrogen is removed for each gallon recycled. There is a point of diminishing

returns with increased recycle flows due to the increased pumping costs. Typically,

plant’s do not recycle more than 80% of the effluent back to the anoxic basin.13 pg2-11

Therefore, the MLE process is able to reach level 1N and 2N depending upon the

amount of nitrogen in a plant’s influent.1 pg86 The MLE process is shown on Figure 5

below.

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Figure 5 A process flow diagram showing the MLE process1 pg69

3.2.3 Denitrification Filters

Denitrification filters are a standalone process that removes nitrate typically with

methanol addition. Methanol is not the only BOD source that can be used. Any waste

stream that is low in nitrogen and high in BOD, such as waste from a brewery, may be

used. Since there are no recycles, the effluent nitrate can theoretically reach zero. One

drawback is that a clarifier is necessary after the denitrification filters in order to collect

the biomass that is washed away from the filter. Additional drawbacks are the cost of

adding BOD and the necessary head to drive flow through the filter. In general,

denitrification filters are used in facilities trying to reach 3N levels.3 pg2-3 A diagram

showing the denitrification filter process is included below.

Figure 6 Denitrification Filters1 pg69

3.2.4 Bardenpho (four-stage)

A four stage Bardenpho process is a MLE process with an additional set of

anoxic and aerobic tanks added to remove nitrate that is inefficient for an MLE process

to remove.13 pg2-13 Additional BOD or methanol does not need to be added to the last

anoxic tank to reduce effluent nitrate, but methanol addition will further improve nitrate

removal. The breakdown of the activated sludge releases BOD that can be used to

remove nitrate, but the breakdown also releases ammonia. Consequently, the

ammonia released is converted in the last aerobic tank. Additionally, the last aerobic

tank is generally necessary to prevent additional denitrification or anaerobic conditions

in the secondary clarifiers. A Bardenpho process can reach levels 2N or 3N, depending

on the influent soluble unbiodegradable nitrogen, carbon source used, and the settling

properties of a plant’s sludge.1 pg88 A process flow diagram is shown in figure below:

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Figure 7 Process Diagram of a 4 Stage Bardenpho1 pg69

3.3 Phosphorus Removal Technologies

3.3.1 Phoredox (A/O)

The Phoredox or A/O process is the simplest scheme that uses EBPR. RAS

is mixed with plant influent which contains high levels of VFAs allowing the PAO

bacteria to grow.13 pg2-27,28 The A/O process is capable of reaching level 1P in most

WRRF, unless the community has major industrial sources.1 pg86 WRRF with good

settling sludge (SVI<90) can reach level 2P. The main advantage of this method is that

no chemicals are necessary and no additional sludge is generated. The drawbacks of

an A/O process are: the additional tankage required, recycle lines need to be

constructed, increased chance or severity of struvite formation in digested sludge, and

periodic failure of EBPR can occur. Also, the effluent particulate phosphorus increases

as EBPR becomes more effective, because each milligram of the plant’s MLSS and

effluent solids contains more phosphorus. Therefore, reaching effluent limits without

filters becomes more difficult as EBPR performs better. A process flow diagram is

shown in figure below:

Figure 8 A/O Process Diagram1 pg80

3.3.2 Chemical Addition

Chemical addition is the process of adding chemicals such as alum, lime, or

ferric chloride to precipitate phosphate. Chemical can be added at any location in a

treatment plant before clarifiers or effluent filters. Chemicals can also be added to

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digester supernatant or other sidestreams that contain high levels of phosphorus.

These sidestreams are often recycled back to the main process.3 pg2-15

One point to note is that chemical should only be added carefully if at all to the

plant influent if the plant is using chemical addition when EBPR is not functioning. If

chemical is added before the anaerobic tank, most of the phosphate can be locked up,

and the PAO bacteria will not have enough phosphorus to function. The PAOs will

wash out of the plant, and reestablishing EBPR will be difficult. An operator will need to

dial back their chemical dosage enough to allow PAOs to form but not too much that

effluent limits are violated.

Chemical addition also generates additional sludge increasing sludge processing

and disposal costs in addition to the costs of the chemicals and increasing the amount

of inert solids which increases a plant’s MLSS. Chemical addition is a reliable process

that gives operators a good deal of flexibility in meeting tier 1 and sometimes tier 2 limits

depending on the efficiency of the secondary clarifiers.1 pg88 The figure below gives a

diagram of chemical addition.

Figure 9 Process Diagram of Chemical Addition1 pg80

3.3.3 Filtration

If a level 2 or level 3 limits are required, often effluent filters will need to be added in

order to remove the particulate nitrogen and phosphorus fractions regardless of the

upstream processes.1 pg89 In some cases, polymer is added before the filters to improve

their efficiency. A process diagram of filtration and chemical addition is shown below.

The downsides of filtration are increased maintenance of the equipment and the head

necessary to drive flow through the filters. The figure below shows a diagram of

chemical addition and filtration.

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Figure 10 Chemical addition and effluent filtration1 pg80

3.3.4 Phostrip

Phostrip, unlike previous phosphorus removal processes, is used exclusively to

treat sidestreams. Up to 40% of plant’s RAS is fed to an anaerobic tank where

phosphorus is released.3 pg2-9 Overflow from the tank is mixed with lime and clarified.

One advantage of this process is that it is not highly dependent upon influent VFAs..12

pg800 Phostrip is able under the right conditions to reach level 1P removal.13 pg5-3 Phostrip

is typically a cost effective method of removing phosphorus because the high

phosphorus overflow is a small waste stream allowing less chemical to be used.1 pg75

Figure 11 Phostrip Process Diagram1 pg80

3.4 Combined Nitrogen and Phosphorus Removal Systems

3.4.1 Three-stage Phoredox (A2O)

The A2O process is a combination of a MLE process and an AO process and

has the drawbacks and advantages of both processes.3 pg2-11 The A2O is able to

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generally meet level 1 treatment for both nitrogen and phosphorus. If the clarifiers

perform above average, level 2 treatment is possible.1 pg87 The figure below shows a

diagram of the A2O process.

Figure 12 A2O Process Flow Diagram1 pg80

3.4.2 Modified (five Stage) Bardenpho

Another process scheme that can remove both nitrogen and phosphorus is a five

stage Bardenpho, which is a Bardenpho process with an anaerobic tank to allow for

EBPR to occur.3 pg2-3,4 A five stage Bardenpho can meet the nitrogen limits of a four

stage Bardenpho or level 2N, and the phosphorus limits of an AO plant or level 1P.1 pg87

The figure below shows a diagram of the five stage Bardenpho process.

Figure 13 Five Stage Bardenpho Diagram1 pg80

3.4.3 University of Cape Town (UCT)

The UCT process is a modification of the A2O process. The return activated

sludge is directed to the anoxic tank to be denitrified, and a phosphorus recycle line is

added to direct sludge to the anaerobic zone.3 pg2-4 In the Bardenpho process, nitrate

containing RAS is sent to the anaerobic zone. The nitrate is consumed by bacteria

using VFAs, before PAOs are able to take up VFAs. Therefore, the UCT process is

more likely to have stable operations in plants that have lower BOD to phosphorus

ratios in their influent. The UCT process is able to meet level 1 and possibly level two

limits. 1 pg87 The figure below gives the process flow diagram for the UCT process.

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Figure 14 UCT Process Flow Diagram1 pg80

3.4.4 Virginia Initiative Process (VIP)

The VIP process is a modification of the UCT process where the phosphorus

recycle is taken from the end of the anoxic zone where the nitrate level should be

lowest.3 pg2-11 The process can reach similar treatment levels as the UCT process. 1 pg87

The figure below shows the process flow diagram for the VIP process.

Figure 15 VIP Process Diagrams1 pg80

3.4.5 Orange Water and Sewer Authority (OWASA)

The base of the OWASA process is an aerobic, anoxic, and aerobic reactor. A

sidestream anaerobic reactor is added to enable the plant to perform EBPR.3 pg2-12

Fermented plant influent, RAS, and a VFA source are added to the anaerobic reactor

where phosphorus release can occur. The OWASA is a good candidate for a plant that

needs additional VFAs to stabilize their EBPR process. The plant is capable of

reaching level 1 nutrient removal.3 pg2-12 The figure below shows a process flow diagram

for the OWASA process.

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Figure 16 OWASA Process Flow Diagram.3 pg2-13

3.4.6 Sequencing Batch Reactors (SBR)

SBRs allow for the treatment of wastewater in one tank rather than sending flow to

different tanks. A typical SBR sequence is to have raw influent added when the nitrate

has been denitrified, and the tank is anaerobic. The VFAs in the raw influent are taken

up by PAOs and phosphate is released. The tank is aerated to allow ammonia to be

nitrified and BOD oxidized. Next, the nitrate is converted nitrogen gas and the activated

sludge is wasted. Finally, the sludge is allowed to settle, and then new influent is

added. SBR processes give a good deal of flexibility to a treatment plant operator

because cycle times can be easily varied based upon the influent to a plant. However,

one SBR must always be available to receive plant influent. In addition, the increased

flexibility can require additional operator time to manage. SBRs without filters are able

to reach level one and sometimes level 2 or 3 removal.3 pg2-2

3.4.7 Surface Aerated Plants

Surface aerated plants such as Orbal, oxidation ditch, racetrack, and Carousel

plants are often used for secondary treatment in Illinois. The oxidation ditch process is

a series of tanks where flow loops. The tanks are typically mixed and aerated by the

same equipment. By varying the dissolved oxygen in the portions of different rings,

anoxic zones can be created where denitrification occurs. Additional recycles or

tankage can be added to create anaerobic zones for EBPR as well. Modified surface

aerated plants are typically only capable of reaching level 1 nutrient limits.3 pg4-6

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Figure 17 Process Diagram of an Oxidation Ditch Plant13 pg2-37

3.4.8 Pearl® Process

The Pearl® process is a propriety system designed to purposely create struvite

pellets from high strength wastewater or from digester supernatant.1 pg83 Magnesium is

added to the wastewater at the base of an upflow reactor. Smaller struvite pellets are

located at the top of the reactor and larger denser particles are located in the lower

section of the reactor. As particles reach a desired size, the pellets are wasted. The

effluent from the process is recycled in order maintain the desired velocity in the reactor.

The Pearl® process is potentially capable of reducing the phosphorus and ammonia

loading to the mainstream of the plant.1 pg83 The process is unlikely to be able to solely

meet a plant effluent nutrient limit. A process flow diagram is shown in figure below

courtesy of Ostara™.

8/22/2014 P a g e | 23 Revision 3

Figure 18 Pearl® Process14

3.4.9 Membrane Bioreactors (MBRs)

MBRs are activated sludge plants which use membranes instead of clarifiers to

remove solids from a plant’s effluent. MBRs allow MLSS concentrations to rise above

those seen in typical WRRF allowing plants to have smaller footprints.3 pg4-39 Also,

MBRs have lower effluent solids resulting in lower particulate nitrogen and phosphorus

in a plant’s effluent. MBRs paired with several of the N and P removal processes above

can reach level 3 limits.1 pg89 MBRs have distinct drawbacks: increased maintenance

requirements, increased pumping costs to force flow through the membrane,

membranes also have to be cleaned regularly to prevent fouling, and membranes are

replaced regularly as they wear.

3.5 Developing Technologies

Current low nutrient limits and the prospect of lower limits in Europe and the

coastal areas of the United States have caused the development of many novel

technologies. Several of these technologies hold the promise to reach tier 3 nutrient

limits or lower for nitrogen and P in a more cost effective or reliable manner. These

technologies are generally biological based processes that need to be piloted in order to

size a plant to remove nutrients.

8/22/2014 P a g e | 24 Revision 3

3.5.1 Simultaneous Nitrification and Denitrification (SND)

SND is a process where the bulk dissolved oxygen is set below 2 �� ��

.3 pg4-39

SND can occur in a conventional activated sludge plant, or a plant using media to grow

a biofilm (MBBR or IFAS). When the bulk dissolved oxygen concentration drops

sufficiently, dissolved oxygen cannot fully penetrate the sludge floc or biofilm.

Therefore, anoxic or anaerobic conditions exist within the floc depending on how far

nitrate or nitrite can diffuse into the floc. When sufficient ammonia and BOD is present

in the bulk solution, the outer layers of a floc can oxidize ammonia to nitrate or nitrite.

The nitrate or nitrite can diffuse into the inner layers of a floc where denitrification can

occur if the bulk BOD concentration is high enough. Generally, the first aerobic tanks in

a conventional activated sludge plant can generate these conditions if the dissolved

oxygen is lowered sufficiently. However, lowering the dissolved oxygen will decrease

the nitrification rate in the aerobic tanks based upon the oxygen concentration profile in

activated sludge flocs. Since activated sludge tanks are sized to be able to maintain

nitrification in winter, a reduced nitrification rate will result in an increase in the

necessary tankage for a BNR plant. The increased volume is not easy to calculate

because it is nearly impossible to determine the oxygen profile in an activated sludge

floc in a functioning plant. To determine the SND rates, a pilot is generally used or

kinetic tests are performed using full-scale activated sludge tanks.

3.5.2 SHARON

SHARON stands for “Single Reactor System for High Activity Ammonium

Removal over Nitrite.” The process involves creating conditions where (AOB) ammonia

oxidizing bacteria are present and nitrate oxidizing bacteria (NOB) are not present.13 pg2-

25 The ammonia is converted to nitrite rather than nitrate, resulting in a lower oxygen

demand and methanol demand if supplementary carbon is being used. The effluent is

then fed to a reactor, where it can be denitrified to nitrogen gas. Sharon is generally

used to treat digester supernatant that is warm (>30°C) and has high ammonia levels.1

pg63 The higher temperatures result in a higher growth rate for AOB allowing for the

process to run at SRTs below 2 days.1 pg63 In these conditions, AOBs will grow quickly

enough to avoid being washed out unlike NOBs.1 pg63

3.5.3 Anammox

Anammox or anaerobic ammonium oxidation microorganisms convert nitrite and

ammonium to nitrogen gas in the absence of oxygen and BOD.6 Therefore, the process

does not require additional methanol, which can reduce the operational costs.

Annammox bacteria grow more slowly than nitrifiers and are sensitive to process

conditions, so skilled and careful monitoring is necessary for this process to function.3

pg6-10 In one way, the low growth rate of Anammox bacteria is an advantage, because

8/22/2014 P a g e | 25 Revision 3

less sludge is produced which reduces sludge disposal costs. Anammox can often be

paired with a SHARON process, which generates the nitrite necessary to metabolize the

remaining ammonia. Anammox processes typically treat industrial waste streams and

anaerobic digested sludge filtrate. The process is known as DEMON® when the

ammonia oxidization and Anammox process occur in the same unit process. The net

equation for the DEMON® (deammonification) is shown below:6

Equation 5 Demon Process

The DEMON® process results in no alkalinity and BOD consumption and limited

oxygen demand with low sludge production. The DEMON® process was successfully

piloted at the Egan WRRF for the Metropolitan Water Reclamation District of Greater

Chicago.6

3.5.4 Algae Reactors

Algae reactors are a promising technology to remove nutrient from wastewater

streams. Algae reactors make use of the organisms that cause water quality issues in

the receiving streams.7 pg5 Algae growth and the diurnal dissolved oxygen concentration

cycling is the primary impairment caused by phosphorus in water bodies. The

technology is currently finishing lab scale testing with pilot scale tests planned using a

50 to 200 gallon reactor.7 pg23 Therefore, the technology will not be ready for use in a

full-scale WRRF for several years.

8/22/2014 P a g e | 26 Revision 3

3.6 Summary of Treatment Technologies

The table gives summary of the levels of treatment for the technologies discussed.

Processes are defined as most likely reaching these limits, possibly reaching these

limits, and add on process to meet these limits.

Level of Treatment Probable Possible Add On Process

1P ( 1�� �

�) A/O

chemical addition Phostrip Pearl

1N ( 8��

�) Step Feed

MLE SND

1 (NP)

(1�� �

� and 8

��

�)

A2O UCT VIP OWASA SBR Oxidation Ditches

Sharon Anammox

2P ( 0.5 �� �

�) A/O

chemical addition Filtration

2N (5��

�) Bardenpho 4 stage MLE Filtration

1P and 2N

( 1�� �

� and 5

��

�)

Bardenpho 5 stage Filtration

2 (NP)

(0.5�� �

� and 5

��

�)

A2O UCT, VIP OWASA SBR Oxidation Ditches

3N (3��

�) Bardenpho 4 stage Denitrification

Filters 3 (NP)

(0.1 �� �

� and 3

��

�)

MBR A2O SBR Oxidation Ditches Bardenpho 5 stage

Algae Reactors

Table 3 Summary of Technologies

8/22/2014 P a g e | 27 Revision 3

4.0 Considerations

Many plant specific factors are involved in determining a facility’s improvements

necessary to perform BNR (Biological Nutrient Removal) of phosphorus. The cost for

treating a plant’s biosolids is a factor in deciding whether a Plant removes phosphorus

biologically or chemically. Chemical addition for phosphorus removal will result in

increased solids production, which increases biosolids processing and disposal costs

and can stress aeration basins, clarifiers, and biosolids handling equipment. As a

result, WWTPs near their design capacity may require facility upgrades.

In some cases, even a plant with high biosolids costs might decide to implement

chemical addition as a stopgap, before additional work is done to meet more stringent

limits depending on the results of the FRIP. A difficulty with this plan is that plants will

need to dial back their chemical dosage in order to establish EBPR(Enhanced Biological

Phosphorus Removal) without exceeding a WRRF’s initial permit of 1.0 �� �

�.

Additionally, any enhanced phosphorus removal process should increase the

phosphorus fraction in the biomass. If biosolids are land applied, the additional

phosphorus in the biosolids may require additional farmland, so treated biomass is

applied at agronomic rates (Title 35, Part 391)

A major consideration is the secondary clarifier performance of a plant. The

effluent solids from a conventional plant typically contain 2% phosphorus.10 pg535 A

conventional plant effluent with a 12 or 25 mg TSS/L limits contains 0.24 to 0.50 �� �

� in

only the solids. Appendix 1 contains the information about individual WRRF as well.

When enhanced biological phosphorus removal (EBPR) is implemented, the effluent

solid’s phosphorus can contain 5% phosphorus or more versus 2% for conventional

plants.10 pg540 In EBPR, the effluent particulate phosphorus can reach 0.6 to 1.25 �� �

�,

which could cause a plant’s effluent to exceed proposed limits without considering the

effluent soluble phosphorus (phosphate) concentration. Also, chemical addition causes

the formation of phosphate containing solids which should increase the effluent solid’s

fraction. Poor clarifier performance and poor biomass settleablility could cause the

need to add effluent filters to a plant to meet proposed phosphorus limits. The addition

of effluent filtration could require additional hydraulic head potentially requiring an

intermediate pump station.

EBPR is another process that can be chosen to remove phosphorus. To initially test

the feasibility of using EBPR, a plant’s influent BOD to total phosphorus (TP) ratio

should be examined, especially seasonal variations. Next, the soluble BOD or readily

biodegradable COD (rbCOD) to phosphorus ratio should be established to determine if

there is sufficient available BOD/COD. The influent BOD/TP ratio can be misleading if

the influent contains a good deal of slowly biodegradable BOD/COD (sbCOD). The

8/22/2014 P a g e | 28 Revision 3

PAO (Poly-Phosphate Accumulating Organisms) need VFAs present in the anaerobic

tank at the head of the plant for “luxury uptake” to occur in aerobic tanks. VFAs are

present in the influent, and rbCOD can be hydrolyzed (broken down) to VFAs in the

anaerobic tank. Slowly biodegradable BOD/COD does not have enough time to break

down to VFAs in the anaerobic tanks, so the sbCOD finishes being hydrolyzed in the

aerated tanks. Therefore, the sbCOD portion of a plant’s influent BOD should not be

used to calculate the feasibility of a plant using EBPR. If a plant contains excess

rbCOD, the WRRFs might be able to reach 0.50 ��

limits without fermentation to

generate additional VFAs.3 pg 3-4

If a plant’s influent contains sufficient BOD but not rbCOD, fermenters will be

needed to reach 1.0 ��

and 0.50

��

consistently.13 pg3-29-31 Fermenters are typically

unaerated tanks constructed to ferment a plant’s influent or RAS sbCOD to VFAs or

rbCODs , which are critical for the PAOs in the anaerobic tanks.

If a plant does not contain sufficient BOD yearly or seasonally, a facility will need to

add chemical regularly to remove some phosphorus. The initial locations to add

chemical are any high concentration phosphorus recycles from solids handling. The

amount of chemical added to remove a pound of phosphorus increases rapidly as a

phosphate concentration drops below 1 ��

.1 pg75 Therefore, the high phosphorus

recycle streams allow for the most phosphorus to be removed with the least chemical

usage. If more phosphorus removal is required, chemical will need to be added in the

main treatment process and/or limits after secondary clarifiers and before effluent filters,

where the phosphate concentration is lowest.

8/22/2014 P a g e | 29 Revision 3

4.1 Cost Ranges

4.2 Qualifiers

Site and facility specific considerations were not included in the cost estimates due

to the high variable costs such as:

• Biosolids Processing Costs

• Capacity of Solids Handling Equipment

• Biosolids Land Application or Disposal Costs

• Plant Hydraulics

• Intermediate Pump Stations

• Cost of Retrofitting Existing Tanks

• Current Process Flow Diagram

• Land Availability Around an Existing WRRF

• Site Specific Chemical Molar Dosage

• Clarifier Capacity

• Rock Excavation

Costs as presented are for adding additional tankage and equipment, and not

retrofitting existing facilities.

4.3 Cost Information

The cost estimating information below is meant to only give rough guidelines on the

costs of implementing certain levels of treatment.

A major factor that influences the cost of biological nutrient removal is the amount of

flow treated at a plant. For example, the cost of treating a gallon of water to level 1

(Nitrogen and Phosphorus) was ten times more expensive per gallon for a 0.1 mgd

WRRF versus a 100 mgd WRRF.3 pg5-14 This ratio stays relatively consistent for lower

effluent limits.3 pg5-18 Additionally, larger facilities have higher staffing levels. These

levels would allow the larger WRRFs to handle the startup and troubleshooting of the

additional biological and chemical processes required of a BNR plant. In addition, the

staffing costs are a higher percentage of the operations and maintenance costs at

smaller plants. For example, staffing consumes 40% of the O&M budget for 1 mgd

facilities versus 20% at 10 mgd plants.13 pg4-34 Overall, BNR is typically easier and more

cost effective to implement at larger facilities.

BNR is also easier at facilities with well settling sludge. Facilities with poor settling

sludge will require filtration to meet a 2P or 0.50 ��

limit . Effluent filtration can add

significant costs to a plant. BNR facilities with filtration were found to be “20% to 40%

more expensive” per gallon than systems performing secondary treatment.4 pg21

8/22/2014 P a g e | 30 Revision 3

Electrical consumption was found to increase by up to 40%.4 pg21-22 Therefore, some

Fox River plants and communities may have a disparate impact from a possible 0.50 ��

limit. Effluent filtration and its associated costs will impact only facilities and

communities with poorly settling sludge and not necessarily all Fox River WRRFs.

Phosphorus limits are expected to come to Fox WRRFs before nitrogen limits. The

cost estimating information will focus on the cost of implementing phosphorus limits for

effluent phosphorus levels of 1.0 ��

, 0.50

��

, and 0.1

��

, which are the effluent

concentrations that are included in the current FRIP model.

USEPA’s “Municipal Nutrient Removal Technologies Reference Document” gives

the present worth for these treatment systems, their 20 year operational costs , and

construction costs in 2007 dollars.13 pg4-22,23 Appendix 2 contains raw data in tables 4

and 5 as well as a sample calculation on how the costs were determined. Figures 19,

20, 21, 22, and 23 below gives the range of construction costs and operations &

maintenance (O&M) costs.

Figures 19: Capital Costs for Adding Chemical Addition3 pg 4-22

8/22/2014 P a g e | 31 Revision 3

Figures 20: Capital Costs for Adding an A/O Process3 pg 4-22

8/22/2014 P a g e | 32 Revision 3

Figures 21: Capital Costs for Adding an A/O Process with Fermenters3 pg 4-22

8/22/2014 P a g e | 33 Revision 3

Figures 22: Capital Costs for Adding an A/O Process with Fermenters and Filters.3 pg 4-22

8/22/2014 P a g e | 34 Revision 3

Figures 23: Capital Costs for Adding an A/O Process with Fermenters, Filters, and

Chemical addition. 3 pg 4-22

The five figures above give a range of construction costs per mgd of plant

capacity for different treatment processes and flow ranges. The large size of the bands

of construction costs are reflective of the cost variability of implementing even similar

treatment technology. For example, two 1 mgd WRRF in Maryland were modified to a

MLE system, and one facilities capital costs were 60% higher.5 pg9

The figures suggest that chemical addition is the most cost effective method of

phosphorus removal. However, the cost of chemical addition does not take into account

the costs of the additional sludge generated. Waste sludge digestion, stabilization, and

disposal costs vary from facility to facility. Total costs, including solids handling costs,

should be taken into consideration for any facility before choosing to only use chemical

addition even as a stopgap.

Enhanced biological phosphorus removal (EBPR) processes such as A/O were

found to have five times the construction costs of chemical addition. Part of the

8/22/2014 P a g e | 35 Revision 3

difference between the life-cycle costs for chemical and biological nutrient removal is

that the tanks and pipes, which are the main cost of EBPR, have a service life of 50

years and in extreme cases tanks have been in service for more than 80 years.

USEPA’s life-cycle analysis is for 20 years or the standard life-cycle for mechanical

equipment.13 pg 4-6 Therefore, USEPA’s method does not take into account the

advantage of EBPR over the full service life of a tank.

Adding a fermenter for VFA production was found to be a small additional cost, and

adding filters was found to add 10% to 20% to the life-cycle costs of a facility. If a

facility needs to reach a limit below 0.50 ���

�, chemical addition after secondary

clarifiers and before filters will probably be required. A WRRF may not need filters if the

facility has well settling.

Figure 24: Annual Additional Operations and Maintenance Costs3 pg 4-22

The operation costs in Figure 24 show that the non-chemical processes have

similar operational expenses. The O&M costs for chemical addition or augmenting the

8/22/2014 P a g e | 36 Revision 3

A/O process are shown to be marginal, but the costs of biosolids are not included.

Therefore, the O&M costs for chemical treatment should be seen as floor for the best-

case scenario.

8/22/2014 P a g e | 37 Revision 3

5.0 Conclusions

• Many biological and chemical treatment process exist to enable Fox River

WRRFs to meet an effluent limit of 1P or 1.0 ��

.

• Chemical addition of ferric, alum, or lime is capable of meeting a 1P or 1.0 ��

with well functioning clarifiers and increased sludge production.

• Several biological process configurations exist to use enhanced biological

phosphorus removal to reach 1.0 ��

effluent limits with reasonable clarifier

performance and sufficient soluble BOD.

• Some WRRFs with well settling sludge (SVI<100) could reach level 2P or 0.50 ��

, but many WRRFs will probably require effluent filters to have effluent

phosphorus concentrations regularly below 0.50 ��

.

• The majority of WRRF will require effluent filters and chemical addition to reach

limits below 0.5 ��

.

• Over a 20 year period, effluent filters increase the cost of a BNR facility by

approximately 20%.4 pg21

• Similar plants with similar capacities in the same region can have significantly

different capital costs for the same upgrades.

• Larger facilities have up to one tenth of the treatment costs per gallon of a

smaller facility.

8/22/2014 P a g e | 38 Revision 3

6.0 References:

1) Nutrient Removal. WEF. New York: McGraw-Hill, 2011. Print.

2) The Cadmus Group, Inc. Nutrient Control Design Manual. Rep. no. EPA/600/R-

10/100. USEPA, 2010. Web. April. 2014.

3) Pagilla, Krishna R., Ph.D.,P.E., and Meltem Urgun-Demirtas, Ph.D. Sustainable

Technology For Achieving Very Low Nitrogen and Phosphorus Effluent Levels.

Tech. no. 02-CTS-1. WERF, IWA, 2009. Web. Apr. 2014.

4) Colorado Water Quality Control Division. Technologies, Performance and Costs

for Wastewater Nutrient Removal and Implementation Recommendations. Rep.

N.p., Nov. 2010. Web. Apr. 2014.

5) Biological Nutrient Removal Processes and Costs. Rep. no. EPA-823-R-07-002.

USEPA, June 2007. Web. Apr. 2014.

6) Qin, Donqi, Ph.D. "Sidestream Nitrogen Removal at the John E. Egan Water

Reclamation Plant by DEMON Process." Watercon 2013. Illinois, Springfield.

Lecture.

7) Pramanik, Amit, Ph.D., Margaret R. Mulholland, Ph.D., Katherine C. Filippino,

Ph.D., Chris Wilson, Ph.D., and Chalres Bott, Ph.D. "Algae Bioreactors as a

Cost-Effective Approach for Enhanced Nutrient Removal." Webinar. 29 Apr.

2014. Web.

8) Bott, Charles B., Ph.D., P.E., BCEE. "Nitrogen Removal 3.0: Integration of

Anammox into Sidestream and Mainstream BNR Processes." Science and

Technology Advisory Committee. Chesapeake Bay Program. Web. Apr. 2014.

9) "Mission Statement." Fox River Implementation Plan. Fox River Study Group,

n.d. Web. 05 June 2014.

10) Rittmann, Bruce E., and Perry L. McCarty. Environmental Biotechnology:

Principles and Applications. Boston: McGraw-Hill, 2001. Print.

11) McFarlane, Austin. "BNR CHALLENGES AT START-UP." Nutrient Removal and

Recovery Workshop. IWEA. 2013. Lecture.

12) Tchobanoglous, George, Franklin L. Burton, and H. David. Stensel. Wastewater

Engineering: Treatment and Reuse. Boston: McGraw-Hill, 2003. Print.

13) USA. EPA. Ann Arbor Michigan. Municipal Nutrient Removal Technologies

Reference Document. By Shin Joh Kang, Ph.D., P.E, Kevin Olmstead, Ph.D.,

P.E.,, Krista Takacs, P.E., and James Collins. R08 ed. Vol. 832. N.p.: n.p., n.d.

Ser. 006. Web. Apr. 2014

14) "The Pearl® Process." Ostara Nutrient Recovery Technologies. Ostara, n.d.

Web. 2 June 2014.

8/22/2014 P a g e | 1 Revision 3

7.0 Appendix 1 NPDES Permit Information

NPDES Number

Facility

Issue Date

Expiration Date

Receiving Stream

Discharge Number

Design Average Flow

Monthly Average BOD mg

Summer Monthly

Ammonia Nitrogen Limit

as mg N/L

Phosphorus

Monthly Average

TSS mg/L

IL0021598

Barrington Wastewater Treatment Facility

02/22/2008

03/31/2013

Unnamed Tributary of Flint Creek

002 STP Outfall

3.68 MGD

10

1.2

-

12

IL0045110

Lake Barrington Community Homeowners Association

09/5/2008

09/30/2013

Fox River

001 STP Outfall

0.455 MGD

25

-

IL0022543

City of Batavia STP

02/23/2007

04/30/2012

Fox Fiver

001 STP Outfall

4.2 MGD

20

1.5

- 25

IL0028282

City of Crystal Lake

5/1/2012

4/30/2017

Crystal Creek

001 STP Outfall

5.8 MGD

10

1.1

1.0

12

IL0053457

City of Crystal Lake WWTP#3

1/25/2008

2/28/2013

Unnamed Tributary of Sleepy Hollow

Creek

001 STP Outfall

1.7 MGD

10

1.2

1.0

12

IL0027944

Carpentersville – Main STP

08/3/2007

09/30/2012

Fox River

001 STP Outfall

4.5 MGD

20

1.5

- 25

IL0022705 City of St Charles East Side WWTF

6/23/2006 6/30/2011 Fox River 001/002 9 MGD 20 1.5 - 25

IL0026808 City of St Charles West Side WWTF

6/7/2012 5/31/2017 Fox River 001 STP Outfall 0.7 MGD 10 1.2 - 12

IL0020516

Village of Cary WWTP

01/11/2006

02/28/2011

Fox River

001 STP Outfall

2.8 MGD

20

1.5

- 25

IL0020877 City of Earlville -STP

8/30/2012

8/31//2017

Indian Creek

002 STP Outfall

0.3764 MGD

10

1.5

-

12

ILG640231

Elgin Water Treatment Plant

05/15/2012

04/30/2017

N/A

- 15

IL0020818

Fox Metro WRD WTP

02/08/2007

03/31/2012

Fox River

001 STP Outfall

42 MGD

10

1.5

- 12

Table 4 NPDES Permits Table 1

8/22/2014 P a g e | 2 Revision 3

NPDES Number

Facility

Issue Date

Expiration Date

Receiving Stream

Discharge Number

Design Average Flow

Monthly Average BOD mg

Summer Monthly

Ammonia Nitrogen Limit

as mg N/L

Phosphorus

Monthly Average

TSS mg/L

IL0028657

Fox River Reclamation District – South STP

01/26/2007

02/29/2012

Fox River

001 STP Outfall

25.0 MGD

10

1.5

-

12

IL0020583

Fox River Grove WWTP

04/11/2008

04/30/2013

Fox River

001 STP Outfall

1.25 MGD

20

4.8

- 25

IL0028665

Fox River Water Reclamation District – North WRP

01/5/2007

02/29/2012

Fox River

001 STP Outfall

7.75 MGD

20

1.5

- 25

IL0035891

Fox River Water Reclamation District West STP

12/21/2006

01/31/2012

Fox River

001 STP Outfall

5.0 MGD

20

1.5

- 25

IL0020087

Geneva – WWTP

10/13/2006

10/31/2011

Fox River

001 STP Outfall

5.0 MGD

20

1.5

- 25

ILG840090 Hanson Material Service – Yard 591

3/23/2012 2/28/2017 - 35

ILG551014 Hoover Outdoor Education Center STP

12/11/2002 2/28/2008 001 STP Outfall 0.0784 mgd 16 - 24

IL0038202 IWC – Terra Cotta STP

1/26/2009 1/31/2014 Sleepy Hollow Creek

001 STP Outfall (Existing Plant)

0.1 MGD 10 1 -

ILG840060 Lafarge Aggregates Illinois, Inc. – Fox River Quarry

3/23/2012 2/28/2017 - 35

IL0078352 Lafarge Elburn, LLC – Elburn Pit

5/29/2009 4/30/2014 Unnamed Ditch Tributary to Blackberry Creek

001, 002 -

ILG640090 Lake Holliday Utilities WTP

5/15/2012 4/30/2017 - 15

IL0021733 Lake in the Hills SD – STP

5/2/2011 4/30/2016 Crystal Lake Outlet 001 STP Outfall 4.5 MGD 10 1.5 1

12

Table 5 NPDES Permit Table 2

8/22/2014 P a g e | 3 Revision 3

NPDES Number

Facility

Issue Date

Expiration Date

Receiving Stream

Discharge Number

Design Average Flow

Monthly Average BOD mg

Summer Monthly

Ammonia Nitrogen Limit

as mg N/L

Phosphorus

Monthly Average

TSS mg/L

IL00277286 Mount Saint Joseph Home – STP

9/6/2013 8/31/2018 Unnamed Tributary to Flint Creek

001 STP Outfall 0.0125 MGD 10 1.2 - 12

IL0027260 Mooseheart Child City and School – STP

7/2/2012 6/30/2017 Fox River 001 STP Outfall 0.154 MGD 25 Monitor

30

ILG580153 Newark Sanitary District STP

12/11/2003 12/31/2007 001 STP Outfall 0.11 MGD 23 - 34

IL0024716 North Barrington Elementary School – STP

7/20/2012 7/31/2017 Unnamed Tributary to Flint Creek

001 STP Outfall 0.005 MGD 10 1.1 -

IL0031933

Northern Moraine Wastewater Reclamation District WWTP

11/12/2008 11/30/2013 Fox River 001 STP Outfall (Existing Plant)

2.0 MGD 20 1.5 -

25

IL0020052 City of Plano STP 1/24/2011 2/29/2016 Big Rock Creek 001 STP Outfall (Existing)

2.44 10 1.4 1.0

12

IL0070874 Port Barrington Shores STP

9/20/2013 8/31/2018 Fox River 001 STP Outfall 0.012 MGD 25 - 30

ILG840083 Prairie Material Sales, Inc. – Yard 93 Elgin

-

IL0068292 Radco Industries, Inc.

6/27/2013 05/31/20/18 Unnamed Tributary to Mill Creek

001 – Non-contact Cooling Water

-

IL0024732 River Grange STP 10/30/2008 10/31/2013 Unnamed Tributary of Fox River

001 STP Outfall 0.008 MGD 10 1.2 - 12

IL0072010 Safety-Kleen Systems, Inc. – Elgin

9/28/2012 9/30/2017 Unnamed Ditch Tributary to Fox River

001 – Stormwater Overflow from Retention Pond

-

IL0030970 City of Sandwich STP

12/13/2011 12/31/2016 Harvey Creek Tributary to the Little Rock Creek

003 STP Outfall 1.5 MGD 10 0.9 - 12

ILG580139 Shabbona STP 12/11/2003 12/31/2007 001 STP Outfall 0.120 MGD 25 - 37

ILIL0031062 Sheridan Sanitary District – STP

8/29/2012 8/31/2017 Fox River 001 STP Outfall 0.368 MGD 25 - 30

IL00020265 Somonauk STP 11/20/2012 10/31/2017 Somonauk Creek 001 STP Outfall 0.30 MGD 10 0.9 - 12

Table 6 NPDES Permit Table 3

8/22/2014 P a g e | 4 Revision 3

NPDES Number

Facility

Issue Date

Expiration Date

Receiving Stream

Discharge Number

Design Average Flow

Monthly Average BOD mg

Summer Monthly

Ammonia Nitrogen Limit

as mg N/L

Phosphorus

Monthly Average

TSS mg/L

IL0026123 US Dept. Of Energy

7/17/2008 7/31/2013 Ferry Creek, Kress, Creek, Indian Creek

001-006 Non-Contact Cooling Water and Stormwater

-

IL0020516 Village of Cary WWTP

1/11/2006 2/28/2011 Fox River 001 STP Outfall 2.8 MGD 20 1.5 -

IL0062260 Village of Elburn 10/19/2006 11/30/2011 Welch Creek 001 WWTP Outlet 1.266 MGD 10 1.1 - 12

IL0068764 Village of Gilberts WWTP

7/26/2011 7/31/2016 Tyler Creek 001 STP Outfall (Existing Facility)

1.0 MGD 10 1.4 1 12

IL0050628 Village of Hinckley STP

2/7/2013 1/31/2018 Little Rock Creek 001 STP Outfall (Existing Plant)

0.2 MGD 10 1.1 - 12

ILG580213 Village of Paw Paw STP

12/11/2003 12/31/2007 001 STP Outfall 0.15 mgd 31 - 46

ILG580236 Village of Waterman STP

12/11/2002 12/31/2007 001 STP Outfall 0.18 mgd 38 - 56

IL0038229 Waubonsee Community College - STP

-

IL0020109 Wauconda WWTP 9/13/2011 9/30/2016 Fiddle Creek 001 STP Outfall (Existing Facility)

1.9 MGD 10 1.1 1 12

IL0034843 Wayne Grade School STP

7/24/2013 7/31/2018 North Branch Norton Creek

001 STP Outfall 0.030 MGD 10 1.2 -

12

IL0001759 Wedron Plan 8/23/1996 8/31/2001

Buck Creek, Fox Riverm, Unamed tributary to Fox River

-

IL0036412 Yorkville-Briston Sanitary District – STP

5/14/2007 5/31/2012 Fox River 001 STP Outfall 3.62 MGD 20 1.5 -

25

Table 7 NPDES Permit Table 4

8/22/2014 P a g e | 1 Revision 3

7.1 Appendix 2 Sample Cost Calculation

The equations in Appendix 2 are only meant as rough estimates.

20 Year Life Cycle Costs (US Dollars 2014) per million gallon treated 1 mgd 5 mgd

10 mgd

Chemical Addition $243 $140 $122

A/O System $1126 $791 $700

A/O with Fermenter $1156 $821 $706 A/O with Fermenter and Filters $1369 $913 $821

Table 8 20 Year Life Cycle Costs per Million Gallons for Various Treatment Systems for

reaching 1.0 ���

� to 0.50

���

� 13 pg4-23

Capital Costs (USD 2014) per

MGD of Capacity 1 mgd 5 mgd 10 mgd

Chemical Addition $0.30 $0.07 $0.05

A/O System $2.46 $1.70 $1.52

A/O with Fermentor $2.46 $1.70 $1.52

A/O with Fermentor and Filters $3.04 $2.13 $1.89

Table 9 Capital Costs per MGD for various treatment systems for reaching 1.0 ���

� to

0.50 ���

�.13 pg4-23

The calculation below are based upon USEPA’s methodology of roughly estimating

the upgrade costs of meeting a 1P limit for a 1 mgd WRRF using the cost information in

chapter 4 for biological or chemical removal. This sample calculation should only be

done to give a “ballpark” guess of the costs of upgrading a facility. The first step is to

determine the total flow treated during the 20 year life cycle.

Equation 6

Volume����� = Flow��� × Years�$����%&' ×365 days

year

Volume����� = 1Million Gallons

day× 20 years ×

365 days

year= 7,300 Million gallons

Next, the present worth of retrofitting the plant as well as loan financing to fund

20 years of operations and maintenance will be determined. We will assume the plant is

8/22/2014 P a g e | 2 Revision 3

using chemical addition or A/O process. The calculation for chemical addition does not

include sludge handling.

Equation 7

Present Worth:; ���� = Volume����� × Cost=%>>%&' ��>>&'

Present Worth:; ����,?@��%?�> = 7,300 Million gallons ×$243

Million Gallon= $1,800,000

Present Worth:; ����,D� = 7,300 Million gallons ×$1126

Million Gallon= $8,200,000

The present worth is multiplied by 1.6 as a safety factor to account for variable

site differences.

Equation 8

Present Worth:; ����,?@��%?�>,E%'�> = Present Worth:; ����,?@��%?�> × 1.6

Present Worth:; ����,?@��%?�>,E%'�> = Present Worth:; ����,?@��%?�> × 1.6 = $2,800,000

Present Worth:; ����,D�,E%'�> = Present Worth:; ����,D� × 1.6 = $13,000,000

To determine the capital costs, equation 9 below is used with the same safety

factor as the present worth analysis.

Equation 9

GHIJKHLMNOPO = GQRK�ST,UVSVUWPX × GHIHYJKZ[\],��T × ^H_`KZ]VUPNa = $ bJLLJQc

GHIJKHLMNOPO,Ude�WUVf = 0.30 × 1gJLLJQc hHLLLQcR

iHZ× 1.6 = $ 0.5 bJLLJQc

GHIJKHLMNOPO,\/k = 2.46 × 1gJLLJQc hHLLLQcR

iHZ× 1.6 = $ 3.9 bJLLJQc