### 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 me thods 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 wastew ater treatment options, and development (if necessary) of cost-effective technologies for trace
metals

P56.004 Passive Treatment ofPoint- 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 Prot ection Agency (EPA) is in the process of determining whether or not to revise the effluent guidelines for the steam electric i ndustry. 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 insta lling new air pollution control technologies (wet flue gas desulfurization [FGD] technologies, se lective catalytic reduction [SCR] technologies, mercury controls), as well as changing coals, which ma y impact power plant wast ewater characteristics. Facilities need accurate data to understand the impa ct of plant operational c hanges on wastewater, so that, if necessary, cost-effective wastewater man agement options can be implemented while complying with current permit limits and negotiating future permits.

**Description** Wastewater characterization will be conducted to eval uate the impact of FGD wa stewater 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, se lenium, 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 optio ns. The chemistry of selenium oxidat ion in the wet FGD will be evaluated in order to optimize selenium wastewater management with traditional SO
2 treatment performance.

The various sampling and analytical approaches fo r 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 devel op 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 dev eloping toxics management options that could reduce environmental discharges and po tentially 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 suffic ient high-quality and accurate data. The project work w ill also assist facilities in respo nding to state and local agencies in permit negotiations. The results will assist wastewater engine ers 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 st akeholders, 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): Wate r Toxics Characterization**  : These reports will summarize field measurements characterizing trace metals in power plant wastewater systems, in cluding a descripti on of the power plant and sampling/analyt ical 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 optim um 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): Wate r Toxics Characterization**  : These reports will summarize field measurements characterizing trace metals in power plant wastewater systems, in cluding a descripti on of the power plant and sampling/analyt ical 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) ar e being installed, the ash pond may be impacted by ammonia (from the fly ash) as well as metals (from the FGD wastew ater). This project will develop integrated approaches for comanaging various so lids 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 a mmonium. The overarching goal of this project is to develop ways to permanently sequester solutes su ch 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 engine ers 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, SC R and wet FGD additions). Periodic workshops will be used to facilitate broader use and awareness of EPRI result s, 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 optimiz e 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 oppor tunity 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] system s) are being installed, their impact on wastewater may require costeffective and reliable technologies to remove trace me tals (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 avai lable technologies can ac hieve only parts-per-billion (ppb) performance levels. Limited EPRI data suggest t hat several forms of selenium may be present in FGD wastewater; the treatment imp lications are now being explored.

**Description** This project will assess and demonst rate promising technolog ies that cost-e ffectively remove trace metals from power plant wa stewaters. EPRI will provide an informed and impartial third-party evaluation of commercially available wastewater treatment tech nologies. The results will as sist 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 technol ogies where the need exists (e.g., mercury and selenium). A bench-scale evaluation is now being co nducted of technologies that may achieve low ppt levels of mercury in effluents. Biological and zero-v alent iron approaches are being evaluated for removal of selenate, which is difficult to treat using traditi onal precipitation technologies. Once successful and appropriate mercury and selenium technologies are i dentified, 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 pr iorities may include boron, chloride, TSS, ammonia, and other trace metals as the need arises.

**Value**

• Evaluates and provides cost-effective, reliabl e 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 w ill assist power plant wa ter engineers and sci entists 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 co rporate environmental sta ff in responding to EPA’s effluent guidelines study.

**2008 Deliverables**

**Deliverable Title & Description Planned**  **Completion Date Deliverable Type** 

**Mercury Treatment Deve lopment 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 Deve lopment and Evaluation**  : This report will summarize EPRI’s evaluation and development of technologies to treat the various forms (or speciati on) 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 dischar ge 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 adv ent of water quality-based effluent limits that allow for the rele ase of very low concentrations of po llutants in plant effluents. As new air pollution controls (e.g., wet flue-gas-desulfurizati on [FGD] systems and selective catalytic reduction [SCR]/selective noncatalytic reduct ion [SNCR] systems) are installed, their impact on wastewater may require cost-effective and reliable approaches to re moving trace metals and other inorganics (e.g., mercury, selenium, arsenic, boron, total suspende d solids [TSS], and ammonia). Power plants require a portfolio of options in addition to traditional chem ical treatment approaches. Passive treatment systems offer a low-cost, low-maintenance altern ative 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 me thod for treating wastewater discharges. Currently, these systems are being used to remove metals, prov iding significant savings compared with chemicalbased approaches. Current research e fforts focus on the development of design criteria for an integrated passive treatment system for treating ammoniated wa stewater 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 su ccessfully design and oper ate a passive treatment system

**How to Apply the Results** The results of this project will allow water engine ers and scientists to properly evaluate and design a passive treatment system for t he treatment of ammoniated wastew ater and associated metals. In addition, EPRI will facilitate broader use and aware ness of the results and software via periodic workshops.

**2008 Deliverables**

**Deliverable Title & Description Planned**  **Completion Date Deliverable Type** 

**Design Guidelines for Constructe d Wetlands, Treatment Planning**  **Tool, Version 2.0** : This manual will provide guidance on designing passive treatment system, with info rmation on efficacy, costs, and operating parameters. 12/31/2008 Software

**Future Year Deliverables**

**Deliverable Title & Description Planned**  **Completion Date Deliverable Type** 

**Implementation Workshop for Op erators Planning To Use the**  **Design Guidelines for Constructe d 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 mi croorganisms, 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 m anaged. 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 plan ts 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 im proving 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 ac oustics—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. T he 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 en vironmentally 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 powe r plant water engi neers 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 whil e maintaining plant efficiency and reliability. Power plants may participate in pilot- and full-scale ev aluations 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 br ief 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 Al ternative Biocides**  : This report will provide a synthesis of pilot and field studies evaluating alternative biocides, including dosage and performance results. 2009 Technical Report