Electric Power Research Institute 

2008 Portfolio 

56 Effluent Guidelines and Water Quality Management 

Program Overview 

Industry Needs and Issues Addressed Key Accomplishments

• Reliable data to support the industry in 

negotiating reasonable, science-based 

regulatory guidelines 

• Cost-effective, reliable wastewater treatment 

options for trace metals and nutrients 

• Data to characterize the fate of trace elements 

in power plant wastewater streams 

• Accurate analytical methods to characterize 

total and speciated trace element 

concentrations in power plant wastewaters 

• Tools to optimize ash pond management of 

total suspended solids (TSS), pH, ammonium, 

and trace metals 

• Alternatives to chlorine for biofouling control 

• Characterization data and predictive tools 

for estimating trace metals in ash pond 

wastewater 

• Screening data identifying potential 

concerns for FGD wastewater 

• Guidelines for optimizing ash pond 

management of TSS and pH 

• Design guidelines for passive treatment 

technologies for traditional wastewater 

constituents and some trace metals 

• Surveys of promising chemical precipitation 

adsorption technologies for power plant 

wastewater treatment 

Value Anticipated Deliverables

• Data and information to assist the U.S. 

Environmental Protection Agency (EPA) in its 

determination of the need for effluent 

guidelines revisions 

• Cost-effective wastewater treatment systems 

with the potential to save O&M costs 

• Strategies to ensure compliance with existing 

or revised permits 

• Optimized ash pond management techniques 

that can avoid the need for costly chemical/ 

physical wastewater treatment, which may cost 

tens of millions of dollars 

• Reliable data to support all stakeholders in 

responding to EPA’s effluent guidelines 

study, as well as to support the industry in 

permit negotiation 

• Wastewater treatment approaches for 

mercury, selenium, and other trace metals 

• Guidelines for integrated ash pond 

management of traditional wastewater 

constituents with trace metals 

• Accurate analytical methods for total and 

speciated selenium, arsenic, mercury, and 

other trace metals in wastewater 

• Alternatives to chlorine for biofouling control 

Industry Involvement

• Estimated total 2008 budget: $1.5 M 

• Program financial leverage: $24:$1 

Program Technical Lead

Paul Chu 

650-855-2812 

pchu@epri.com

 p. 1 
EPRI 2008 Portfolio p. 2

56 Effluent Guidelines and Water Quality Management

Summary of Projects

Project Number Project Title Value 

P56.001 Wastewater Toxics 

Characterization and 

Analytical Methods 

Data and analytical methods to evaluate and characterize the 

impact of flue gas desulfurization (FGD) technologies and other air 

pollution controls on wastewater 

P56.002 Integrated Management 

of Ash Ponds 

Optimization of ash pond management of TSS, pH, ammonium, 

and other trace metals 

P56.003 Cost-Effective, LowWaste Wastewater 

Effluent Control 

Evaluation of promising wastewater treatment options, and 

development (if necessary) of cost-effective technologies for trace 

metals 

P56.004 Passive Treatment of 

Point- and Non-pointSource Aqueous 

Discharges 

Alternative, lower-O&M-cost treatment options to traditional 

chemical precipitation and adsorption technologies 

P56.005 Nonoxidizing Biocides for 

Biofouling Control 

Environmentally friendly alternatives to chlorine for biofouling 

control 

Project Descriptions 

P56.001 Wastewater Toxics Characterization and Analytical Methods (101139) 

Issue 

The U.S. Environmental Protection Agency (EPA) is in the process of determining whether or not to revise 

the effluent guidelines for the steam electric industry. Reliable data will be needed to support the 

stakeholder community in providing EPA with the best information available to arrive at reasonable, 

science-based regulatory guidelines. Power plants are installing new air pollution control technologies 

(wet flue gas desulfurization [FGD] technologies, selective catalytic reduction [SCR] technologies, 

mercury controls), as well as changing coals, which may impact power plant wastewater characteristics. 

Facilities need accurate data to understand the impact of plant operational changes on wastewater, so 

that, if necessary, cost-effective wastewater management options can be implemented while complying 

with current permit limits and negotiating future permits.

Description 

Wastewater characterization will be conducted to evaluate the impact of FGD wastewater and wastewater 

management options to comply with existing permit limits and to assist in negotiating future permits. 

Studies will evaluate the partitioning of trace metals (e.g., mercury, selenium, arsenic) in the FGD solids 

(gypsum) and wastewater. 

The form or speciation of some metals (specifically selenium and arsenic) impacts health as well as 

wastewater treatment options. The chemistry of selenium oxidation in the wet FGD will be evaluated in 

order to optimize selenium wastewater management with traditional SO2 treatment performance. 

The various sampling and analytical approaches for selenium, arsenic, and mercury will be evaluated 

using power plant matrices to determine suitable approaches. EPRI will monitor EPA analytical method 

development efforts and work to develop alternative approaches as needed. 
EPRI 2008 Portfolio p. 3

56 Effluent Guidelines and Water Quality Management

Value 

• Provides credible, accurate data to inform the EPA effluent guidelines study 

• Improves risk management and supports development of science-based regulations 

• Provides data for permit negotiations by developing predictive estimates for trace substance 

concentrations in wastewater, as well as developing toxics management options that could 

reduce environmental discharges and potentially reduce operating costs 

How to Apply the Results 

Project findings and deliverables will be employed by personnel in environmental affairs/compliance in 

responding to EPA’s effluent guidelines study, so that the stakeholders have sufficient high-quality and 

accurate data. The project work will also assist facilities in responding to state and local agencies in 

permit negotiations. The results will assist wastewater engineers and scientists in developing wastewater 

management options for new FGD systems, as well as evaluating the potential impact of other plant 

operations changes (e.g., coal changes). In addition, EPRI will facilitate broader use and awareness of 

the results by holding periodic briefings for key stakeholders, including regulatory and other government 

agencies; developing materials for the trade press/media; and continuing service on various advisory 

panels.

2008 Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type

Field Site Report(s): Water Toxics Characterization: These reports 

will summarize field measurements characterizing trace metals in 

power plant wastewater systems, including a description of the power 

plant and sampling/analytical methods employed. 

12/31/2008 Technical Update 

Selenium Speciation Analytical Methods Evaluation: This report 

will summarize EPRI’s evaluation of the various analytical methods 

and protocols for determining the different species of selenium in 

power plant wastewater. 

3/31/2009 Technical Update 

Impact of Wet FGDs on Wastewater: This technical update will 

synthesize the latest FGD wastewater characterization data. It will also 

evaluate various wastewater management approaches and how this 

wastewater stream may impact final effluent discharges. 

12/31/2008 Technical Update 

Evaluation of Selenium Oxidation in Wet FGDs: This technical 

update will provide a summary of bench-scale and field data 

evaluating the chemistry of how selenium oxidizes in wet FGD 

systems, as well as approaches to managing the oxidation to obtain 

forms of selenium that are optimum for wastewater treatment and 

general FGD operation. 

12/31/2008 Technical Update 

Future Year Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

Arsenic Speciation Measurement Evaluation: EPRI will evaluate the 

various arsenic speciation methods. Additional characterization studies 

will be conducted, as necessary, and all the results synthesized. 

2009 Technical Update 

Field Site Report(s): Water Toxics Characterization: These reports 

will summarize field measurements characterizing trace metals in 

power plant wastewater systems, including a description of the power 

plant and sampling/analytical methods employed. 

2009 Technical Update 
EPRI 2008 Portfolio p. 4

56 Effluent Guidelines and Water Quality Management

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

Water Toxics Characterization Summary Report: This report will 

synthesize the available water toxics characterization data and provide 

an assessment of potential issues and wastewater management 

options for power plant wastewater streams. 

2009 Technical Report 

P56.002 Integrated Management of Ash Ponds (055830) 

Issue 

Many power plants currently operate ash ponds primarily for solids settling to meet total suspended solids 

(TSS) limits. Water discharge permits have become increasingly stringent, allowing for release of very low 

concentrations of pollutants in plant effluents. As new air pollution controls (e.g., selective catalytic 

reduction [SCR] systems, flue gas desulfurization [FGD] systems) are being installed, the ash pond may 

be impacted by ammonia (from the fly ash) as well as metals (from the FGD wastewater). This project will 

develop integrated approaches for comanaging various solids and solutes that occur in water of coal-ash 

settling ponds. 

Description 

Common constituents on National Pollutant Discharge Elimination System (NPDES) permits for ash pond 

discharges include selenium, chromium, pH, TSS, and ammonium. The overarching goal of this project is 

to develop ways to permanently sequester solutes such as selenium and chromium in ash sediments. 

However, simultaneous dissolution of other metals, such as mercury, must be avoided, particularly if the 

pond is managed with a food web that includes fish. Another goal is to manage nutrient (nitrogen and 

phosphorus) species to avoid creating algal blooms that can increase TSS and cause high pH. Future 

efforts will include optimization of ash pond designs (physical structure) to maximize the ability of 

operators to manage the ponds as treatment facilities. 

Value 

• Optimizes ash pond treatment of TSS, pH, ammonium, and trace metals 

• Reduces O&M costs 

• Enhances compliance to achieve stringent trace metal and organic effluent limits 

How to Apply the Results 

Project findings and deliverables will be employed by wastewater engineers and scientists in developing 

wastewater management options for ash pond management, as well as evaluating the potential impact of 

plant operations changes (e.g., coal changes, SCR and wet FGD additions). Periodic workshops will be 

used to facilitate broader use and awareness of EPRI results, as well as provide a forum for utilities to 

share their experiences and results. 

2008 Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type

Guidelines for Integrated Management of Multiple Constituents in 

Fly Ash Ponds, Vol. III: These guidelines will provide power plant 

operators with a tool to optimize ash pond management for TSS and 

other criteria pollutants, along with trace metals, pH, and nutrients. 

12/31/2008 Technical Report 
EPRI 2008 Portfolio p. 5

56 Effluent Guidelines and Water Quality Management

Future Year Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

Case Studies Report for Integrated Management of Ash Ponds: 

This workshop will facilitate broader use and awareness of EPRI 

results, as well as an opportunity for utility wastewater 

engineers/scientists to share operating experiences and best 

management practices. 

2009 Technical Resource 

P56.003 Cost-Effective, Low-Waste Wastewater Effluent Control (052395) 

Issue 

Water discharge permits are becoming increasingly stringent, allowing for release of very low 

concentrations of pollutants in plant effluents. This trend may accelerate through, for instance, revised 

effluent guidelines. As new air pollution controls (e.g., selective catalytic reduction [SCR] systems, wet 

flue-gas-desulfurization [FGD] systems) are being installed, their impact on wastewater may require costeffective and reliable technologies to remove trace metals (e.g., mercury, selenium, arsenic, boron, total 

suspended solids [TSS], and ammonia). Some states are requiring low parts-per-trillion (ppt) mercury 

discharge levels, even though the commercially available technologies can achieve only parts-per-billion 

(ppb) performance levels. Limited EPRI data suggest that several forms of selenium may be present in 

FGD wastewater; the treatment implications are now being explored. 

Description 

This project will assess and demonstrate promising technologies that cost-effectively remove trace metals 

from power plant wastewaters. EPRI will provide an informed and impartial third-party evaluation of 

commercially available wastewater treatment technologies. The results will assist power plants in 

evaluating treatment options as well as in responding to the U.S. Environmental Protection Agency’s 

(EPA’s) effluent guidelines study. 

As necessary, EPRI will seek to develop technologies where the need exists (e.g., mercury and 

selenium). A bench-scale evaluation is now being conducted of technologies that may achieve low ppt 

levels of mercury in effluents. Biological and zero-valent iron approaches are being evaluated for removal 

of selenate, which is difficult to treat using traditional precipitation technologies. Once successful and 

appropriate mercury and selenium technologies are identified, pilot- and full-scale evaluations will be 

conducted at various power plant sites. EPRI will also evaluate the various commercial approaches for 

arsenic, as well as developing technologies such as hybrid-ion exchange. EPRI will also evaluate the 

applicability of zero liquid discharge. Other future priorities may include boron, chloride, TSS, ammonia, 

and other trace metals as the need arises. 

Value 

• Evaluates and provides cost-effective, reliable and environmentally protective wastewater 

treatment approaches and options to achieve increasingly stringent trace metal and organic 

effluent limits 

• Reduces O&M costs 

• Enhance compliance 

• Maintains overall plant reliability 
EPRI 2008 Portfolio p. 6

56 Effluent Guidelines and Water Quality Management

How to Apply the Results 

Project findings and deliverables will assist power plant water engineers and scientists in providing 

wastewater treatment options for new FGD systems, ash ponds, and other low-volume waste streams. 

Power plants can participate in hosting pilot- and full-scale evaluations of promising wastewater 

treatment. The results will also be employed by corporate environmental staff in responding to EPA’s 

effluent guidelines study.

2008 Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type

Mercury Treatment Development and Evaluation: This report will 

summarize EPRI’s evaluation and development of treatment 

approaches to achieve ultralow levels of mercury discharges in power 

plant wastewater streams. 

12/31/2008 Technical Report 

Selenium Treatment Development and Evaluation: This report will 

summarize EPRI’s evaluation and development of technologies to 

treat the various forms (or speciation) of selenium in power plant 

wastewater streams. 

3/31/2009 Technical Report 

Evaluation of Zero Liquid Discharge: This technical update will 

provide an engineering evaluation of the potential applicability and 

limitations of zero liquid discharge for FGD wastewater and other 

power plant wastewater streams. 

6/30/2008 Technical Update 

Future Year Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

Arsenic Treatment Evaluation: EPRI will evaluate the treatment 

performance and limitations of various commercial approaches for 

precipitation and adsorption of arsenic, as well as developing 

technologies such as hybrid-ion exchange technology. 

2009 Technical Update 

Literature/Vendor Wastewater Survey Update: Other Trace 

Elements: As appropriate, EPRI will survey the available literature and 

interview treatment vendors to evaluate wastewater treatment options 

for other metals and pollutants of interest (e.g., boron, chromium, 

chloride, ammonia, and TSS). 

2009 Technical Update 

P56.004 Passive Treatment of Point- and Non-point-Source Aqueous Discharges 

(SP1756) 

Issue 

Water discharge permits are becoming increasingly stringent with the advent of water quality-based 

effluent limits that allow for the release of very low concentrations of pollutants in plant effluents. As new 

air pollution controls (e.g., wet flue-gas-desulfurization [FGD] systems and selective catalytic reduction 

[SCR]/selective noncatalytic reduction [SNCR] systems) are installed, their impact on wastewater may 

require cost-effective and reliable approaches to removing trace metals and other inorganics (e.g., 

mercury, selenium, arsenic, boron, total suspended solids [TSS], and ammonia). Power plants require a 

portfolio of options in addition to traditional chemical treatment approaches. Passive treatment systems 

offer a low-cost, low-maintenance alternative for meeting discharge limits. 
EPRI 2008 Portfolio p. 7

56 Effluent Guidelines and Water Quality Management

Description 

Passive treatment systems can be a cost-effective method for treating wastewater discharges. Currently, 

these systems are being used to remove metals, providing significant savings compared with chemicalbased approaches. Current research efforts focus on the development of design criteria for an integrated 

passive treatment system for treating ammoniated wastewater and associated metals, including mercury, 

employing a field-scale pilot passive treatment system. As part of this research, spiking of the passive 

treatment system with mercury, arsenic (III and V), and selenium (IV and VI) will be undertaken to support 

the development of the design criteria.

Value 

• Provides design information on efficacy, costs, and operating parameters 

• Provides software and a design manual to successfully design and operate a passive treatment 

system 

How to Apply the Results 

The results of this project will allow water engineers and scientists to properly evaluate and design a 

passive treatment system for the treatment of ammoniated wastewater and associated metals. In 

addition, EPRI will facilitate broader use and awareness of the results and software via periodic 

workshops. 

2008 Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type

Design Guidelines for Constructed Wetlands, Treatment Planning 

Tool, Version 2.0: This manual will provide guidance on designing 

passive treatment system, with information on efficacy, costs, and 

operating parameters. 

12/31/2008 Software 

Future Year Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

Implementation Workshop for Operators Planning To Use the 

Design Guidelines for Constructed Wetlands, Treatment Planning 

Tool, Version 2.0.: A workshop for EPRI members will serve as a 

training and distribution channel for the Design Guidelines. 

2009 Workshop, Training, 

or Conference 

Design Guidelines for the Passive Treatment of Ammoniated 

Wastewater and Associated Metals: The Design Guidelines manual 

will assist users in the treatment of ammoniated wastewater and 

associated metals using passive treatment system technology. 

2009 Technical Report 

P56.005 Nonoxidizing Biocides for Biofouling Control (101136) 

Issue 

Biofouling is the undesirable accumulation of microorganisms, plants, and animals on heat transfer 

surfaces such as condenser tubes. Managing biofouling is critical, as such accumulation reduces the heat 

transfer rate and can lead to material corrosion. Biofouling can lead to significant plant efficiency and 

availability problems unless it is controlled and managed. Chlorine is commonly used for biofouling 

control; however, this use of chlorine will likely become more limited due to regulatory restrictions. 

Alternative approaches are needed that will allow plants to maintain efficient operations with lower 

maintenance costs. 
EPRI 2008 Portfolio p. 8

56 Effluent Guidelines and Water Quality Management

Description 

This research will provide nontoxic alternatives to oxidizing biocides for biofouling control, aiming to 

provide environmental benefits while maintaining or improving facility thermal performance. As this work 

progresses, pilot studies will be used to quantify the economics and performance of emerging options, 

leading to full-scale trials at participant sites. EPRI has achieved promising results in bench-scale 

development of two technologies—enzymes and pulsed acoustics—as alternatives to oxidizing biocides. 

Promising technologies will be evaluated through pilot studies at various power plant sites to evaluate 

both micro- and macrofouling. These technologies may minimize or eliminate the need for oxidizing 

biocides such as chlorine for biofouling control. The research is targeted predominantly at heat-transfer 

surfaces but may also be applicable to process water systems. 

Value 

• Provides environmentally acceptable alternatives to chlorine for biofouling control 

• Improves or maintains plant heat rates using environmentally acceptable options for controlling 

biofouling and also possibly reducing corrosion in cooling and service water systems 

How to Apply the Results 

Project findings and deliverables will assist all power plant water engineers and scientists in minimizing 

biofouling where chlorine use is restricted. Operating guidelines will assist water engineers and scientists 

in managing service and cooling water biofouling while maintaining plant efficiency and reliability. Power 

plants may participate in pilot- and full-scale evaluations of alternative biocide approaches.

2008 Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type

Field Site Report: The results from the field evaluation of alternative 

biocides will be summarized, describing their efficacy, potential issues, 

and limitations, as well as giving a brief description of the power plant, 

test conditions, and test methodology. 

12/31/2008 Technical Update 

Future Year Deliverables 

Deliverable Title & Description Planned 

Completion Date Deliverable Type 

O&M Guidelines for Alternative Biocides: This report will provide a 

synthesis of pilot and field studies evaluating alternative biocides, 

including dosage and performance results. 

2009 Technical Report