Final 

Sampling Episode Report 

EME Homer City Generation L.P.’s 

Homer City Power Plant 

 Homer City, PA 

Episode 6548 

Prepared for:

U.S. Environmental Protection Agency 

Engineering and Analysis Division 

Office of Water 

1200 Pennsylvania Avenue, NW 

Washington, D.C. 20460 

Prepared by: 

Eastern Research Group, Inc.

14555 Avion Parkway 

Suite 200 

Chantilly, VA 20151 

26 August 2008 

EPA Contract No. 68-C02-095 

Work Assignment 5-22
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CONTENTS 

Page 

1. INTRODUCTION .................................................................................................................1-1 

1.1 Background of Detailed Study.............................................................................1-1 

1.2 Power Plant Site Selection...................................................................................1-1 

1.3 Sampling Episode Overview................................................................................1-2 

2. PLANT OVERVIEW.............................................................................................................2-1 

2.1 FGD Scrubber System .........................................................................................2-2 

2.2 FGD Wastewater Treatment System ...................................................................2-3 

2.3 Bottom Ash Treatment System............................................................................2-6 

3. SAMPLE COLLECTION .......................................................................................................3-1 

3.1 Sampling Points, Sample Collection Methods, and Field Measurements ...........3-1 

3.1.1 Influent to FGD Wastewater Treatment ..................................................3-2 

3.1.2 Second-Stage Clarifier Overflow in FGD Wastewater Treatment ..........3-4 

3.1.3 Effluent from FGD Wastewater Treatment .............................................3-6 

3.1.4 Effluent from Bottom Ash Pond..............................................................3-7 

3.2 List of Analytes and Sample Preservation...........................................................3-9 

3.3 Plant Operational Data.......................................................................................3-10 

3.4 Deviations from the Sampling and Analysis Plan .............................................3-10 

4. LABORATORY ANALYTICAL RESULTS AND DISCUSSION...................................................4-1 

4.1 Measured and Calculated Results for FGD Influent Samples .............................4-1 

4.2 FGD Wastewater Treatment System ...................................................................4-4 

4.3 Bottom Ash Pond Treatment System...................................................................4-4 

5. DATA QUALITY.................................................................................................................5-1 

5.1 Analytical Quality Control...................................................................................5-1 

5.2 Field Quality Control ...........................................................................................5-1 

5.2.1 Bottle Blanks............................................................................................5-1 

5.2.2 Equipment Blanks....................................................................................5-2 

5.2.3 Field Blanks .............................................................................................5-2 

5.2.4 Field Duplicates .......................................................................................5-4 

6. REFERENCES .....................................................................................................................6-1 

Appendix A: ANALYTICAL RESULTS

Appendix B: ANALYTICAL DATA FOR METALS, FGD WASTEWATER AND BOTTOM ASH POND

Appendix C: DATA REVIEW NARRATIVES

Appendix D: PICTURES FROM THE SAMPLING EPISODE
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LIST OF TABLES 

Page 

2-1 Homer City NPDES Monitoring Requirements for the FGD Effluent............................ 2-6 

3-1 Sample Collection Information, Homer City................................................................. 3-13 

3-2 Number of Samples Collected by Sampling Point, Homer City ................................... 3-14 

3-3 Field Measurements, Homer City.................................................................................. 3-15 

3-4 Analytical Methods and Procedures for Samples Collected at Homer City.................. 3-16 

3-5 Summary of Sample Container and Planned Preservation ............................................ 3-17 

3-6 Sample Preservation Summary, Homer City................................................................. 3-18 

3-7 Generating Unit Operating Characteristics During Sample Collection, Homer City.... 3-20 

3-8 FGD Scrubber System Operating Characteristics, Homer City..................................... 3-20 

3-9 FGD Wastewater Treatment System Operating Characteristics, Homer City............... 3-21 

3-10 Bottom Ash System Operating Characteristics, Homer City......................................... 3-21 

4-1 Biphasic Sample Results for Low-Level Total Metals and Routine Total Metals 

Measured Above the Report Limit, FGD Influent, Homer City...................................... 4-5 

4-2 Biphasic Sample Results for Routine Total Mercury, FGD Influent, Homer City.......... 4-7 

4-3 Biphasic Sample Results for Classical Analytes Measured Above the Report Limit, 

FGD Influent, Homer City............................................................................................... 4-7 

4-4 Classical Pollutants Measured Above the Report Limit for the FGD Wastewater 

Treatment System, Homer City ....................................................................................... 4-8 

4-5 Metals Measured Above the Report Limit for the FGD Wastewater Treatment 

System, Homer City......................................................................................................... 4-9 

4-6 Classical Pollutants Measured Above the Report Limit for the Bottom Ash Pond 

Effluent, Homer City ..................................................................................................... 4-12 

4-7 Metals Measured Above the Report Limit for the Bottom Ash Pond Effluent, Homer 

City................................................................................................................................. 4-13 

5-1 Field Blank Results Measured Above the Report Limit, Homer City............................. 5-5 

5-2 Field Duplicate Results, Homer City............................................................................... 5-6 

A-1 FGD Influent Analytical Data, Homer City.................................................................... A-1 
LIST OF TABLES (Continued) 

Page 

iii

A-2 ProChem Biphasic Filtration Blank Analytical Results, Homer City............................. A-9 

A-3 FGD Second-Stage Clarifier Overflow Effluent Analytical Data, Homer City ........... A-10 

A-4 FGD Effluent Analytical Data, Homer City ................................................................. A-14 

A-5 Duplicate of FGD Effluent Analytical Data, Homer City ............................................ A-19 

A-6 Bottom Ash Effluent Analytical Data, Homer City...................................................... A-24 

A-7 Bottle Blank and Equipment Blank Analytical Data, Homer City ............................... A-29 

A-8 FGD Influent Field Blank Analytical Data, Homer City.............................................. A-36 

A-9 FGD Second-Stage Clarifier Overflow Field Blank Analytical Data, Homer City...... A-37 

A-10 FGD Effluent Field Blank Analytical Data, Homer City ............................................. A-41 

A-11 Bottom Ash Effluent Field Blank Analytical Data, Homer City.................................. A-45 

B-1 Analytical Results for Metals in the FGD Wastewater Treatment System, Homer 

City...................................................................................................................................B-1 

B-2 Analytical Results for Metals in the Bottom Ash Pond Effluent, Homer City................B-3 
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LIST OF FIGURES 

Page 

2-1 FGD Wastewater Treatment System, Homer City Power Plant...................................... 2-8 

D-1 Sampler Working Inside a “Cleanbox”........................................................................... D-1 

D-2 Sample Tap Splitter at the Influent to FGD Wastewater Treatment System.................. D-2 

D-3 Sampling Set Up at the Influent to FGD Wastewater Treatment System (SP-1) ........... D-3 

D-4 Sample Collection Point for the 2nd Stage Clarifier Overflow ....................................... D-4 

D-5 Sampling Set Up for the 2nd Stage Clarifier Overflow (SP-2)........................................ D-5 

D-6 Sample Collection Point for the Effluent from the FGD Wastewater Treatment 

System............................................................................................................................. D-6 

D-7 Sampling Set Up at Effluent from FGD Wastewater Treatment System (SP-3)............ D-7 

D-8 Sampling Set Up at Effluent from the Bottom Ash Pond (SP-4) ................................... D-8 
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1. INTRODUCTION

 The Engineering and Analysis Division (EAD) of the U.S. Environmental Protection 

Agency (EPA) has been conducting a program that consists of site visits and sampling at steam 

electric power plants to characterize raw wastewaters generated by coal-fired steam electric 

power plants, as well as to evaluate treatment technologies and best management practices used 

to reduce pollutant discharges. This Sampling Episode Report (SER) describes the sampling 

activities that took place on 21 August 2007 through 23 August 2007 at EME Homer City 

Generation L.P.’s Homer City Power Plant (Homer City), located in Homer City, Pennsylvania 

(Sampling Episode 6548). The focus of Episode 6548 was to characterize the influent to and 

effluent from the flue gas desulfurization (FGD) wastewater treatment system, as well as the 

second stage clarifier overflow within the FGD wastewater treatment system and the effluent 

from the bottom ash ponds at Homer City. 

1.1 Background of Detailed Study

 Section 304(m) of the Clean Water Act (CWA) requires EPA to develop and publish a 

biennial plan that establishes a schedule for the annual review and revision of national effluent 

limitations guidelines and standards (ELGs) required by CWA section 304(b). During EPA’s 

2005/2006 review of ELGs, EPA determined that the steam electric power generating point 

source category (40 CFR Part 423) was the second-largest discharger of toxic-weighted 

pollutants. EPA’s analyses indicated that the toxic-weighted loadings were predominantly driven 

by metals present in wastewater discharges, and that the waste streams contributing the majority 

of the metals are associated with air pollution controls. Other potential sources of metals include 

coal pile runoff, metal/chemical cleaning wastes, coal washing, and certain low-volume wastes. 

 In the 2005/2006 study, EPA noted certain data limitations that affected the Agency’s 

estimate of the potential hazards posed by discharges from this category. Therefore, EPA 

determined that further review of these discharges during the 2007/2008 ELG planning cycle 

was warranted. EPA has concentrated its efforts for the 2007/2008 study on better characterizing 

the sources generating the pollutants responsible for the majority of the toxic-weighted pollutant 

loadings and available pollution control technologies/practices for steam electric plants. 

1.2 Power Plant Site Selection

 EPA selected six coal-fired steam electric plants for wastewater sampling. EPA based the 

plant selection on the process configurations and characteristics of the plants, as well as the site 

visits conducted for the study. The following characteristics (not listed in any priority order) 

were used to select plants for sampling: 

• Coal-fired boilers; 

• Wet FGD scrubber system, including: 

— Type of scrubber, 

— Sorbent used, 

— Year operation began, 

— Chemical additives used, 

— Forced oxidation process, 
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— Water cycling, and 

— Solids removal process; 

• FGD wastewater treatment system; 

• Type of coal; 

• NOx controls; 

• Ash handling systems; 

• Ash treatment system; and 

• Mercury air controls. 

 EPA selected Homer City for sampling based on the following site characteristics: 

• The plant is a coal-fired power plant that burns eastern bituminous coal in each of 

its three generating units; 

• The plant operates a wet FGD system that is a limestone forced oxidation system; 

• The plant adds formic acid to the FGD system to increase the sulfur dioxide 

removal efficiency; 

• The plant operates a segregated FGD wastewater treatment system, which 

includes the following steps: 

— Equalization; 

— First-stage chemical precipitation; 

— First-stage clarification; 

— Second-stage chemical precipitation; 

— Second-stage clarification; 

— Nutrient/phosphoric acid addition; 

— Heat exchange; 

— Biological treatment; and 

— Sand filtration. 

• The plant operates an SCR on the scrubbed unit (Unit 3); and 

• The plant produces a commercial-grade gypsum by-product. 

1.3 Sampling Episode Overview

 On February 6, 2007, EPA and its technical contractor, Eastern Research Group, Inc. 

(ERG), conducted a site visit at Homer City. The purpose of the site visit was to learn about the 

wastewater treatment operations, regarding the FGD scrubber purge, and to gather information in 

order to collect wastewater samples at Homer City. Information collected during the site visit is 

documented in Engineering Site Visit Report for EME Homer City Generation L.P.’s Homer City 

Power Plant [1] and was used to create Sampling Plan, EME Homer City Generation L.P.’s 

Homer City Power Plant (Sampling Plan) [2], which describes the sample collection procedures 

used during the sampling episode. 

 For this sampling episode, EPA arrived at Homer City on Tuesday, August 21, 2007, to 

review the sampling points, determine the set up for the sample collection, label sample bottles, 

and purchase any additional supplies needed for the sampling episode. EPA then collected the 

samples specified in the Sampling Plan on Wednesday, August 22, and Thursday, August 23, 

2007. The following personnel participated in EPA’s sample collection activities: 
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• Ron Jordan, EPA/EAD; 

• Josh Hall, EPA/EAD; 

• TJ Finseth, ERG; 

• Sarah Holman, ERG; and 

• Jessica Wolford, ERG. 

In addition, during the sample collection, EPA collected split samples with the Utility Water Act 

Group (UWAG), acting on behalf of the plant. 
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2. PLANT OVERVIEW

 Homer City operates three coal-fired steam electric generating units. Homer City burns 

approximately five million tons of eastern bituminous coal per year. Units 1 and 2, which came 

on line in 1969, each have a capacity of 650 megawatts (MW) and burn mid-sulfur coal. Unit 3, 

which came on line in 1977, has a capacity of 700 MW and burns high-sulfur coal. Typically, 

Homer City produces between 13 and 14 million MW-hrs annually. The Homer City plant is 

located on approximately 2,400 acres near Homer City, Pennsylvania, near Two Lick Creek and 

Blacklick Creek. 

 Homer City is part of the Pennsylvania, New Jersey, and Maryland (PJM) electricity grid 

and adjusts its MW output based on the grid’s needs (typical fluctuation may be 20 to 30 MW). 

During the summer and winter, Homer City typically operates at maximum or close to maximum 

load 24 hours per day. During the spring and fall, the plant may reduce its load at night to 50 

percent of its capacity. 

 Units 1 through 3 have the following configuration: 

• Boiler; 

• SCR system; 

• Air preheater; 

• Electrostatic precipitator (ESP); and 

• FGD system (Unit 3 only). 

 In 2001, Homer City retrofitted Unit 3 with a wet FGD scrubber system to control the 

sulfur dioxide releases from the plant. Unit 3 is subject to New Source Performance Standards 

(NSPS) air regulations. Plant personnel report that, after installing the FGD scrubber on Unit 3, 

the total plant sulfur dioxide emissions were reduced by 40 percent to comply with new permit 

limits, and the mercury emissions were reduced by 55 percent. The mercury reductions are based 

on the mercury removal across the Unit 3 FGD scrubber as tested by the Department of Energy 

(DOE) during 2001. At the time the FGD scrubber was installed on Unit 3, Homer City also 

installed an FGD wastewater treatment system to control the discharges from the wastewater 

generated during the operation of the FGD scrubber. Section 2.1 discusses the FGD system and 

Section 2.2 discusses the FGD wastewater treatment system. 

 Between 2000 and 2001, Homer City retrofitted Units 1 through 3 with selective catalytic 

reduction (SCR) systems to control nitrogen oxide (NOx) releases from the plant. Plant 

personnel report that, after installing the SCR systems, the total plant NOx emissions were 

reduced by 80 percent to comply with new permit limits. Plant personnel estimate that the SCR 

systems on Units 1 through 3 remove approximately 60 to 90 percent of the NOx from the flue 

gas. Homer City currently operates the SCR systems from May 1 through September 30 each 

year. 

 In the SCR systems, the plant injects only the amount of ammonia needed to convert the 

NOx in the flue gas to nitrogen and water. Excess unreacted ammonia from the SCR system, 

caused by flue gas fluctuations, is known as “ammonia slip.” As the flue gas passes over the 

catalyst in the SCR process, some of the sulfur dioxide is oxidized to sulfur trioxide, which 

combines with unreacted ammonia to form ammonium bisulfate. Ammonium bisulfate can cause 
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fouling and corrosion in air preheaters. The plant typically operates the SCR systems with less 

than two percent ammonia slip to avoid fouling the air preheater with the ammonium bisulfate 

by-product. Typically, without bisulfate fouling, air preheaters are washed once a year for 8 to 12 

hours using ash recycle water at a flow rate of 1,000 gallons per minute (gpm). 

 Homer City has taken steps to reduce air emissions beyond installing FGD and SCR 

systems. Homer City also cleans the coal used in Units 1 and 2 in an on-site process that reduces 

the sulfur content of the coal. The boilers in Units 1 through 3 are equipped with low NOx 

burners and separated overfire air (SOFA) systems, which limit the production of NOx. 

 Homer City utilizes electrostatic precipitators (ESPs) to remove greater than 99.8 percent 

of the fly ash from the flue gas emitted from Units 1 through 3. There is no wastewater generated 

from the operation of the ESPs or fly ash handling system at Homer City. Fly ash is 

pneumatically transferred to silos where it is stored until it is trucked to the on-site, unlined ash 

landfill or beneficially used at the on-site, lined coal refuse site. 

2.1 FGD Scrubber System

 Homer City operates one wet FGD scrubber system on Unit 3, downstream of the ESP, to 

control the emission of sulfur dioxide from the unit. The FGD system is a five-level spray tower 

that uses limestone as the sorbent. 

 The plant has a limestone storage pile on site that contains approximately 30,000 tons of 

Pennsylvania limestone. The plant uses a ball mill to crush the limestone prior to mixing it with 

blowdown water from the Unit 3 cooling tower to create the absorbent limestone slurry used in 

the FGD scrubber. Storm water from the limestone storage and handling area drains to a pond 

and the water is pumped into the FGD make up water tank. 

 The limestone slurry is pumped to the various levels of the scrubber tower (typically 

three or four levels out of the five are operated at one time) and sprayed downward into the 

scrubber. As the flue gas flows up through the tower, countercurrent to the spray, droplets of the 

absorbent slurry absorbs and reacts with the sulfur dioxide in the flue gas to produce calcium 

sulfite. To increase the sulfur dioxide removal efficiency of the scrubber, the plant adds formic 

acid to the system, which buffers the solution and aids in dissolution of the calcium carbonate. 

The plant previously used dibasic acid (DBA), but found that it reduced the selenium removal 

efficiency of the FGD wastewater treatment system. According to Homer City personnel, the 

FGD system removes approximately 97 to 99 percent of the sulfur dioxide from the Unit 3 flue 

gas. Adding the formic acid increases the sulfur dioxide removal by approximately two percent 

and allows the plant to operate the system with one less spray level (i.e., up to four levels instead 

of all five). The reduction in the FGD operating cost outweighs the additional cost to operate a 

biological reactor to remove the formic acid in the FGD wastewater treatment system, which is 

discussed in Section 2.2. 

 The slurry that collects at the bottom of the FGD scrubber is agitated to keep the solids in 

suspension. A forced oxidation system, in which compressed air is introduced into the bottom 

slurry, further oxidizes calcium sulfite to calcium sulfate (gypsum). The slurry is recycled up to 

the various spray levels until the chlorides concentration in the slurry reaches approximately 

15,000 to 20,000 ppm. The spray tower is constructed of Inconel, a superalloy used in high-
2-3

temperature applications that is resistant to oxidation and corrosion. This material can withstand 

up to 25,000 ppm chlorides. When the slurry reaches the maximum allowable solids 

concentration, the plant blows down some of the slurry from the scrubber and adds fresh makeup limestone slurry to the scrubber. Homer City personnel estimate that blowdown occurs daily 

for approximately 12 to 18 hours. During blowdown, the solids level of the slurry typically 

decreases from 15 to 13 percent. 

 During blowdown, the gypsum slurry is sent to primary hydrocyclones, in which solid 

gypsum is separated from the water by centrifugal force. The solid gypsum is forced outward to 

the walls of the hydrocyclones and falls downward, while the water exits the top of the 

hydrocyclones. The gypsum from the primary hydrocyclones is transferred to vacuum filter belts. 

Approximately 80 percent of the supernatant overflow from the primary hydrocyclones is 

recycled back to the scrubber and the remaining 20 percent is transferred to secondary 

hydrocyclones. Homer City recently brought the secondary hydrocyclones on line to further 

reduce the solids content of the supernatant overflow before it is transferred to the FGD 

wastewater treatment system. A portion of the supernatant overflow from the secondary 

hydrocyclones is transferred to the FGD wastewater treatment system and a portion is recycled 

back to the scrubber. 

 The gypsum is rinsed on the vacuum filter belt to reduce the chloride concentration using 

blowdown from Unit 3’s cooling tower as rinse water. As the gypsum is rinsed and dried, water 

that falls through or around the belt is collected and recycled back to the absorber. There is an 

optimal gypsum crystal size range for manufacturing wallboard, and the pores of the vacuum 

filter belts are sized accordingly. If the gypsum crystals are too small, they pass through the 

pores and are recycled back to the scrubber where they continue to grow. The gypsum typically 

contains 30 to 40 percent moisture at the beginning of the vacuum filter belt and 10 percent 

moisture in the final gypsum product. The gypsum falls off the vacuum filter belt and is 

conveyed to a domed structure for storage. Homer City produces gypsum that is light in color 

and contains less than one percent impurities, which is mostly fly ash. Homer City produces 

about 1,000 tons of gypsum per day and sells it to a wallboard manufacturer in Pittsburgh for 

about $1/ton. 

2.2 FGD Wastewater Treatment System

 The FGD wastewater treatment system is designed to receive intermittent discharges of 

FGD wastewater from the secondary hydrocyclones at a flow rate of approximately 220 gpm. 

The intermittent discharges typically occur for 12 to 18 hours per day. The plant operates the 

FGD wastewater treatment system 24 hours per day. The Homer City FGD wastewater treatment 

system contains the following treatment operations: 

• Equalization; 

• First-stage chemical precipitation: 

— Lime addition for pH adjustment, and 

— Ferric chloride, cationic polymer, and air addition for metals 

precipitation/coagulation; 

• First-stage clarification with anionic polymer addition; 
2-4

• Second-stage chemical precipitation: 

— Lime addition for pH adjustment, and 

— Ferric chloride, cationic polymer, and air addition for metals 

precipitation/coagulation; 

• Second-stage clarification with anionic polymer addition; 

• Micronutrient (typically urea), phosphoric acid, and corn syrup addition for 

biological treatment; 

• Heat exchange; 

• Aerobic biological treatment; and 

• Sand filtration. 

 Figure 2-1 presents a process flow diagram of the FGD wastewater treatment system, as 

well as the sampling locations for three of the four sampling points for EPA’s sampling episode. 

 Overflow from the FGD hydrocyclones is transferred directly to the feed tank of the FGD 

wastewater treatment system, where the intermittent flows from the hydrocyclones are equalized, 

allowing the plant to pump a constant flow rate of FGD wastewater through the treatment 

system. The flow rate exiting the feed tank of the FGD wastewater treatment system is typically 

about 110 gpm. Homer City typically adds about 10 to 20 gpm of chemical feed (i.e., lime, ferric 

chloride, and polymer) to the FGD wastewater treatment system; therefore, the flow rate exiting 

the FGD wastewater treatment system averages about 120 gpm. The hydraulic residence time for 

the entire FGD wastewater treatment system is about 3.5 days. The flow rate into the wastewater 

treatment system from the equalization tank during the sampling episode was approximately 109 

gpm (based on one measurement recorded from the flow meter at 1:11 PM on 22 August 2007, 

during sample collection). In addition, the flow rate into the wastewater treatment system from 

the equalization tank on 21 August 2007, ranged from 105 gpm to 113 gpm (based on continuous 

electronic flow monitoring provided to EPA by Homer City). 

 The feed tank is agitated to prevent calcium from settling and scaling the tank. The 

hydraulic residence time in the 150,000-gallon feed tank is about 22 hours. Homer City typically 

maintains the wastewater volume in the feed tank at about 40 to 80 percent of the total tank 

volume. Water from the feed tank is transferred continuously (24 hours per day) to a first-stage 

chemical precipitation tank (referred to hereinafter as the “first-stage neutralization tank”, as 

named by Homer City), in which lime is added to adjust the pH of the wastewater from 6.0 to 

8.1. The plant also adds ferric chloride for metals precipitation, and cationic polymer and air to 

further enhance the precipitation/coagulation. From the first-stage neutralization tank, the 

wastewater is transferred to the first-stage clarifier, in which anionic polymer is added for 

coagulation. The majority of the heavy solids (mainly calcium sulfate and calcium carbonate) are 

removed in the first-stage clarifier. 

 Homer City personnel indicated that excess solids entering the first-stage clarifier can 

interfere with metals precipitation and removal. In particular, Homer City is concerned about 

interference with selenium removal, which affects the plant’s ability to meet its NPDES permit 

limit of 0.8 mg/L total selenium. In an attempt to reduce this interference, Homer City recently 

added a second set of hydrocyclones to the gypsum dewatering system for additional gypsum 

solids removal upstream of the FGD wastewater treatment system, as discussed in Section 2.1. 

With the secondary hydrocyclones operating, the wastewater entering the FGD wastewater 

treatment system contains less than one percent solids. 
2-5

 Water from the first-stage clarifier is transferred to the second-stage chemical 

precipitation tank (referred to hereinafter as the “second-stage neutralization tank”, as named by 

Homer City), in which lime is added to adjust the wastewater pH to 8.1. The plant also adds 

ferric chloride for metals precipitation, and air and occasionally cationic polymer to further 

enhance the precipitation/coagulation. When the plant initially began operating the FGD 

wastewater treatment system, it also added organosulfide to the second-stage neutralization tank 

for mercury removal; however, the plant has since determined that sufficient mercury removal 

can be achieved without the addition of organosulfide. 

 From the second-stage neutralization tank, wastewater is transferred to the second-stage 

clarifier, in which anionic polymer is added for coagulation. The hydraulic residence time across 

each of the 50,000-gallon first- and second-stage clarifiers is approximately 7.5 hours. Prior to 

adding the secondary hydrocyclones, Homer City removed more metals in the second-stage 

clarifier than the first-stage clarifier, due to a better iron hydroxide floc, which plant personnel 

attribute to the lower solids content in the second-stage clarifier. Sludge from the clarifiers is 

transferred to a thickener and then to a vacuum filter. Some sludge from the clarifiers and 

thickener is recycled to the 1st stage neutralization tank to prevent scaling on the tank walls. 

Recycling the sludge introduces crystals into the tank and scaling preferentially occurs on the 

crystal surfaces. 

 Overflow from the second-stage clarifier is transferred to the pH adjustment tank, in 

which micronutrients (typically urea), phosphoric acid, and corn syrup are added to ensure 

growth of microorganisms in the biological reactor. In the past, Homer City has added HCl or 

lime to adjust the pH to 7.5 to 8.0 prior to biological treatment; however, the overflow from the 

second-stage clarifier is typically at the appropriate pH and adjustment is not necessary. From 

the pH adjustment tank, water is transferred through a heat exchanger to the biological reactor. 

The microorganisms in the aerobic biological reactor reduce the organic content and the 

associated biochemical oxygen demand (BOD) of the wastewater. BOD in the FGD wastewater 

is a result of the formic acid that is added to the limestone slurry in the FGD scrubber system. 

Flow through the biological reactor is continuous. The hydraulic residence time in the 350,000-

gallon biological reactor is about 2 days. Sludge from the biological reactor is transferred to the 

thickener, where it is combined with the clarifier sludge and then transferred to the vacuum filter. 

The vacuum filter reduces the sludge moisture content from approximately 60 to 70 percent 

down to 20 percent. Homer City generates 25 tons per day of filter cake (mostly calcium 

sulfate/gypsum) from the vacuum filters, which the plant tests to ensure compliance with 

leachability requirements, and then disposes of this sludge in the on-site, unlined fly ash landfill. 

Homer City generates approximately 3,840 gallons per day (gpd) of filtrate from the vacuum 

filters, which is transferred to the wastewater treatment feed tank. The vacuum filter filtrate 

accounts for approximately 2.4 percent of the total influent to the FGD wastewater treatment 

system. 

 Wastewater from the biological reactor is transferred through sand filters. Wastewater 

from the sand filters is transferred continuously to an effluent tank, except when the filters are 

backwashed. Homer City backwashes the sand filters once every 12 hours for about 15 minutes. 

The backwash is directed to a sump, which also collects all floor drain wastewater. Wastewater 

from the sump is transferred to the FGD wastewater treatment system feed tank a few times per 

day (about 4,000 gallons per transfer). Homer City generates approximately 2,400 gpd of sand 
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filter backwash each day, which accounts for 1.5 percent of the total influent flow to the FGD 

wastewater treatment system. 

 Wastewater from the effluent tank is discharged through NPDES Outfall #027 to 

Blacklick Creek. The flow rate exiting the effluent tank varies from about 70 to 170 gpm due to 

the operation of the variable frequency drive that maintains a constant level in the effluent tank; 

the average flow rate is about 120 gpm. Homer City estimates that the hydraulic residence time 

in the 3,000-gallon, agitated effluent tank is about 12 to 13 minutes. The flow rate of the effluent 

from the wastewater treatment system during the sampling episode was approximately 107 gpm 

(based on the average of 12 measurements recorded randomly at different frequencies from the 

flow meter during sample collection on August 22, 2007). 

 Table 2-1 presents Homer City’s NPDES permit requirements for effluent from the FGD 

wastewater treatment system, which is Outfall #027. 

Table 2-1. Homer City NPDES Monitoring Requirements for the FGD Effluent 

Parameter Daily Minimum Daily Maximum Monthly Average

Total Suspended Solids (TSS) NA 100 mg/L 30 mg/L 

Carbonaceous Biochemical Oxygen Demand 

(CBOD5) 

NA 50 mg/L 25 mg/L 

Oil & Grease NA 20 mg/L 15 mg/L 

Temperature NA 110 NA 

pH 6.0 s.u. 9.0 s.u. NA 

Beryllium NA 1.6 mg/L 0.8 mg/L 

Lead NA 0.2 mg/L 0.1 mg/L 

Selenium NA 1.6 mg/L 0.8 mg/L 

Boron Monitor and Report 

Methylene Blue Active Substances (MBAS) Monitor and Report 

Osmotic Pressure Monitor and Report 

Total Dissolved Solids (TDS) Monitor and Report 

Flow Rate Monitor and Report 

NA – Not applicable. 

 EPA collected a sample of the influent to Homer City’s FGD wastewater treatment 

system downstream of the feed tank and upstream of the first-stage neutralization tank (i.e., the 

sample was collected prior to any chemical addition). EPA collected an interim sample within 

Homer City’s FGD wastewater treatment system at the overflow of the second-stage clarifier. 

EPA also collected a sample of the effluent from Homer City’s FGD wastewater treatment 

system directly from the effluent tank. 

2.3 Bottom Ash Treatment System

 Homer City uses water to sluice the bottom ash and other slag produced from the bottom 

of each boiler. Homer City sluices the bottom ash from the Unit 1 and Unit 2 boilers for 

approximately 90 minutes every 12 hour shift (i.e., two times per day) for both units. In 
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addition, Homer City sluices the bottom ash from the Unit 3 boiler for approximately 45 minutes 

every 12 hour shift. 

 The bottom ash sluice water is piped from the boilers to hydrobins, which remove 90 to 

95 percent of the solids. The dewatered bottom ash from the hydrobins is either used locally for 

antiskid and road construction or placed in the on-site, unlined ash landfill. The supernatant 

overflow from the hydrobins drains to ash settling ponds. 

 Homer City operates four ash settling ponds. The plant typically operates two ash settling 

ponds at one time, which are operated in parallel. Each ash pond has an approximate volume of 

1.76 million gallons. The ash settling ponds receive overflow from the bottom ash hydrobins, as 

well as stormwater runoff. Approximately six acres of storm water drains into the ponds from the 

ash handling and precipitator areas. Water is transferred from the ash settling ponds to a clear 

well via weirs, which are on the opposite side of the ponds from the inlet pipes. From the clear 

well, water is recycled for use as bottom ash sluice. There is a periodic discharge from the clear 

well through the NPDES Outfall #005, the frequency of which depends on the amount of rainfall 

that has been received. The discharge from the clear well is limited to less than 30 mg/L average 

TSS and a pH of 6.0 to 9.0 s.u. The ash settling ponds are cleaned every six to eight months. The 

recovered solids are transported to the on-site, unlined fly ash landfill. 

 EPA collected a sample of the effluent from Homer City’s bottom ash ponds directly 

from the clear well. 
2-8 

Figure 2-1. FGD Wastewater Treatment System, Homer City Power Plant 
3-1 

3. SAMPLE COLLECTION

 During the Homer City sampling episode, the sampling team followed the sample 

collection protocols specified in the Sampling Plan [2]. Section 3.1 describes the sampling 

points, sample collection methods, and field measurements. Section 3.2 describes the list of 

analytes and the sample preservation procedures. Section 3.3 discusses the plant operational data 

collected during the sampling episode. Finally, Section 3.4 discusses any deviations from the 

planned sampling activities described in the Sampling Plan. 

3.1 Sampling Points, Sample Collection Methods, and Field Measurements

 This section describes the sampling points, sample collection methods followed, and the 

field measurements obtained for this sampling episode. Additional details are available in 

Section 3 of the Sampling Plan. Figure 2-1 presents a flow diagram of the FGD wastewater 

treatment plant including sampling point locations. Note that the sampling point at the effluent of 

Homer City’s bottom ash ponds is not shown in Figure 2-1. 

 Table 3-1 lists the sampling points, sampling point descriptions, type of sample 

collection, sample collection dates and times, and the EPA Sample Control Center (SCC) sample 

numbers. Table 3-2 lists the sampling point numbers and descriptions, the number of samples 

collected, and the pollutant parameters analyzed for this sampling episode. Table 3-3 presents the 

field measurement data collected from each of the sampling points. 

 The sampling points collected during this episode were: 

• SP-1: Influent to FGD Wastewater Treatment System; 

• SP-2: Second-Stage Clarifier Overflow in FGD Wastewater Treatment System; 

• SP-3: Effluent from FGD Wastewater Treatment System; 

• SP-4: Effluent from Bottom Ash Pond; 

• SP-5: Duplicate of Effluent from FGD Wastewater Treatment System (SP-3); 

• SP-6: Influent to FGD Wastewater Treatment System (SP-1) Field Blank; 

• SP-7: Second-Stage Clarifier Overflow in FGD Wastewater Treatment System 

(SP-2) Field Blank; 

• SP-8: Effluent from FGD Wastewater Treatment System (SP-3) Field Blank; and 

• SP-9: Effluent from Bottom Ash Pond (SP-4) Field Blank. 

 For all the sampling points (except the total mercury and low-level total metals field 

blank samples at SP-6), EPA collected split samples with Homer City’s representative. Prior to 

the sampling episode, Homer City personnel installed a splitter on the sampling tap at the 

influent to the FGD wastewater treatment system (SP-1), which allowed for split sample 

collection. At all of the other sampling points, EPA inserted a “Y” splitter into the sample tubing 

configuration to allow for split sample collection. For this sampling episode, all analytes, other 

than HEM/SGT-HEM were collected as “true” splits (i.e., samples for the same analyte were 

collected simultaneously). The HEM/SGT-HEM samples were either collected using a bottle 

dipper, or directly from a sample tap; therefore, EPA and Homer City’s representative collected 

duplicate samples, with one filling the bottle immediately after the other. However, for the 

influent to the FGD wastewater treatment system, SP-1, because the splitter was installed in the 
3-2 

sample tap, EPA and Homer City’s representative were able to collect “true” splits for the 

HEM/SGT-HEM sample. 

 The field blank samples at the influent to the FGD wastewater treatment system (SP-6) 

for the low-level total mercury and low-level total metals samples were not collected as split 

samples between EPA and Homer City’s representative. These samples were collected using 

separate blank water and separate tubing. However, the field blank samples for the low-level 

dissolved metals samples were collected as “true” split samples. For a description of the field 

blank sample collection procedures, see Section 5.2.3. 

 At each of the nine sampling points, EPA collected low-level metals sample fractions 

following EPA Method 1669 collection protocols. To collect low-level metals samples, EPA 

samplers donned Tyvek® suits and dust masks (dust masks were worn until all low-level 

mercury samples had been collected) during sample collection. In addition, EPA set up a 

“cleanbox,” which consists of a portable plastic rectangular box with a shallow lip and a flip-top 

lid that secures itself open with clips. The “cleanbox” is double-bagged with a clear inner bag, 

enclosed in a translucent outer bag. The “cleanbox” is handled using “clean hands / dirty hands” 

techniques, whereby the inner bag is handled only by the “clean hands” sampler. When the 

“cleanbox” is opened, the sampler is able to position his/her hands in the box and pull the bag 

over the opening of the box, but is still able to see the sample bottles and tubing. The “cleanbox” 

minimizes potential atmospheric contamination during sample collection. Figure D-1, in 

Appendix D, presents a picture of a sampler working inside a “cleanbox.” To collect samples, 

EPA placed the sample bottles and the inner bag into the “cleanbox” following the protocols 

specified in Method 1669, also referred to as “clean hands / dirty hands” protocols. Sampling 

staff filled the sample container and closed the sample bottle lid and inner bag as quickly as 

possible within the “cleanbox.” The sample bottles were then placed into the outer bag 

following the “clean hands / dirty hands” protocols. 

3.1.1 Influent to FGD Wastewater Treatment 

 The influent to FGD wastewater treatment system (SP-1) was collected from a sample tap 

located on the wastewater piping downstream of the feed tank on the discharge side of the 

transfer pump, and upstream of the first-stage neutralization tank. The sample point thus 

represents a mixture of FGD purge and backwash from the sand filters. Based on average flow 

rates and frequency of the FGD purge, vacuum filter filtrate, and filter backwash, the effluent 

from the feed tank is approximately 110 gpm, comprised of approximately 96 percent FGD 

purge, 2.5 percent vacuum filter filtrate, and 1.5 percent filter backwash. 

 Homer City’s sample tap and valve at SP-1 (as normally configured) is located 

approximately 15 feet above the ground. To aid in sample collection, Homer City installed a 

length of stainless steel pipe (Swagelok tubing) from the sample tap (15 feet above the ground) 

to just below waist level. In addition, Homer City installed a stainless steel splitter, with sample 

valves, to allow split samples to be collected. Figure 2-1 identifies the sampling location for SP1. This sample was collected as a grab sample because the batch discharges from the gypsum 

dewatering process were equalized in the feed tank prior to sample collection and were expected 

to be fairly homogeneous. The sampling point was located inside; therefore, there were no wind 

or rain concerns during the sample collection. 
3-3 

 Prior to collecting the samples at the influent to the FGD wastewater treatment system 

(SP-1), the sampling team purged the newly installed stainless steel piping for five minutes 

(about 10 gallons of wastewater purged). The sampling team then collected field blanks (SP-6) 

for low-level total mercury and low-level total metals. See Section 5.2.3 for a description of the 

field blank sample collection procedures at the influent to the FGD wastewater treatment system. 

 EPA collected the wastewater samples at the influent to the FGD wastewater treatment 

system by attaching a 5-foot length of silicone tubing to one of the fittings on the splitter at the 

sample location (Homer City’s representative attached an identical piece of silicone tubing to the 

other fitting). Figure D-2, in Appendix D, presents a picture of the sample tap splitter installed at 

the influent to the FGD wastewater treatment system by Homer City. After the samplers attached 

the silicone tubing, they opened the valves of the sample tap to purge the tubing. While the 

tubing was being purged, the end of the EPA tubing fell on the ground. EPA removed the 

previous piece of tubing from the tap and attached a new, identical piece of precleaned tubing to 

the tap. Although this newly attached piece of tubing was not used to collect the field blanks, 

EPA does not expect it to be an issue because the tubing sets were identical and were cleaned 

during the same batch. In addition, the supplier of the tubing provided equipment blank results 

for the tubing sets (see Section 5.2.2). 

 After the new tubing was attached, EPA purged the new tubing for four minutes before 

beginning sample collection. Flow from the tap did not stop until all samples were collected 

(except HEM/SGT-HEM and the dissolved metals samples). 

 After the four-minute purge time had elapsed, the samplers filled three 10-liter containers 

with sample, which were later used to pump off the low-level and routine dissolved metals 

sample fractions. Once the 10-liter containers were filled, one member of the sampling team 

transported the three 10-liter containers to the staging area to allow the solids in the wastewater 

to settle while the remainder of the sampling team stayed at the sampling point and continued 

sample collection. Figure D-3, in Appendix D, presents a picture of the sampling set up at the 

influent to the FGD wastewater treatment system. 

 EPA then collected the low-level total metals, low-level total mercury, low-level 

dissolved mercury, routine total metals, as well as the QC samples for each analyte, and the 

arsenic/selenium speciation samples in a “cleanbox,” as described in Section 3.1. The sampling 

team then collected BOD, Group I, and Group II samples by pouring the sample directly from 

the tubing into the sample bottles without using a “cleanbox.” To collect the HEM/SGT-HEM 

samples, the samplers shut off the valve for the sample tap, removed the tubing from the fitting, 

reopened the valve, and filled the sample bottles directly from the tap to prevent any oil and 

grease adhering to the sides of the tubing. 

 During the sample collection, the sampling team collected an aliquot of sample for field 

testing. Sample pH and temperature were measured immediately at the sampling point using a 

pH meter and four-color pH paper. The four-color pH paper was used as an independent check of 

the pH meter to ensure that similar results were measured. After returning to the staging area, the 

sampling team took measurements of free and total residual chlorine using a colorimeter. Table 

3-3 presents the field measurement data for the influent to the FGD wastewater treatment system. 

The samplers noted that the field test jar was initially cloudy and had a brownish-gray 
3-4 

appearance when collected. However, the solids in the sample settled quickly, leaving a layer of 

solids at the bottom of the jar. 

 The sampling team then moved to the staging area, where a pump-off station was set up, 

to collect the low-level and routine dissolved metals samples. The pump-off station consisted of 

a length of Teflon® tubing attached to a length of silicone tubing, which was threaded through 

an ISCO peristaltic pump. The sampling team attached a capsule filter to the silicone tubing, 

which was a short distance downstream of the pump. The sampling team attached another short 

length of silicone tubing to the capsule filter effluent, which was attached to a “Y” splitter and 

two lengths of silicone tubing. This set-up allowed EPA to collect “true” split samples with 

Homer City’s representatives. Prior to collecting any dissolved metals samples of the FGD 

wastewater influent, the samplers collected a field blank sample (SP-6) for low-level dissolved 

metals. See Section 5.2.3 for a description of the dissolved metals field blank sample collection 

at the influent to the FGD wastewater treatment system. 

 After the field blank sample was collected, the sampling team transferred the end of the 

Teflon® tubing into one of the 10-liter containers filled with wastewater from the influent to the 

FGD wastewater treatment system. By this time, the solids in the wastewater had been settling 

for approximately 2.5 hours, and there was approximately a one-inch layer of solids at the 

bottom of the container. 

 The sampling team first purged the tubing and filter with sample for 30 seconds 

(approximately 1 L). The samplers then collected the low-level dissolved metals sample, as well 

as the low-level dissolved metals QC sample. After the low-level dissolved metals samples were 

collected, the samplers transferred the end of the Teflon® tubing into another 10-liter container, 

installed a new capsule filter, and purged the tubing and filter for 30 seconds (approximately 1 L 

of sample). The samplers then collected the routine dissolved metals sample, the routine 

dissolved metals QC sample, and the routine hexavalent chromium sample. 

3.1.2 Second-Stage Clarifier Overflow in FGD Wastewater Treatment 

 The second-stage clarifier overflow in the FGD wastewater treatment system (SP-2) was 

collected from the overflow weir of the clarifier, at the point where the wastewater enters the 

pipe to transfer the wastewater to the pH adjustment tank. To aid in sample collection, Homer 

City constructed scaffolding directly against the clarifier to allow the samplers easy access the 

overflow weir. Figure 2-1 identifies the sampling location for SP-2. This sample was collected as 

a grab sample, because the flow through the FGD wastewater treatment system is continuous; 

therefore, the wastewater characteristics should be fairly homogeneous. 

 During the sample collection at the second-stage clarifier in the FGD wastewater 

treatment system, the sampling team covered the sample collection area with a tarp to cover the 

samplers and sample bottles in case of rain, and prevent debris from falling on the sample 

collection area. There was no rain during the sample collection period. 

 Prior to collecting the samples for the second-stage clarifier overflow in the FGD 

wastewater treatment system (SP-2), the sampling team collected field blanks (SP-7) for lowlevel total mercury, low-level total metals, routine total metals, low-level dissolved metals, lowlevel hexavalent chromium, routine dissolved metals, and routine hexavalent chromium. See 
3-5 

Section 5.2.3 for a description of the field blank sample collection procedures for the secondstage clarifier overflow in the FGD wastewater treatment system. 

 EPA collected the wastewater samples for the second-stage clarifier overflow in the FGD 

wastewater treatment system by pumping samples from the overflow weir into the sample 

containers. EPA attached one end of a 25-foot length of Teflon® tubing to a piece of PVC pipe. 

A sampling team member stood on the scaffolding and submerged the open end of the PVC pipe 

and tubing in the overflow weir. Figure D-4, in Appendix D, presents a picture of the tubing 

submerged in the second-stage clarifier weir. The sampling team positioned the tubing along the 

side of the scaffolding to reach the sampling team at ground level and attached it to a piece of 

silicone tubing, which was threaded through an ISCO peristaltic pump. The sampling team 

attached a “Y” splitter to the end of the silicone tubing, with two additional pieces of silicone 

tubing attached to the “Y” splitter. The length of silicone tubing between the pump and the “Y” 

splitter consisted of two pieces with a small connector, which allowed EPA to attach and detach 

a capsule filter inline with the tubing configuration. The “Y” splitter allowed EPA to collect 

“true” split samples with Homer City’s representative. Figure D-5, in Appendix D, presents a 

picture of the sampling set up for the second-stage clarifier overflow in the FGD wastewater 

treatment system. 

 After EPA configured the tubing for the sampling point, the samplers purged the tubing 

with sample. After approximately 20 seconds of purging, the tubing detached from the filter due 

to backpressure. The samplers were able to recover the filter and tubing without contaminating 

any equipment. The samplers reattached the tubing to the filter and continued purging for two 

minutes. 

 After the tubing was purged, the samplers first collected the low-level dissolved metals 

and low-level hexavalent chromium samples because the capsule filter was already inline with 

the tubing configuration from the dissolved metals field blank sample collection. The sampling 

team then installed a new capsule filter, purged the filter for one minute, and collected the 

routine dissolved metals and routine hexavalent chromium samples. Each of these samples was 

collected in a “cleanbox,” as described in Section 3.1. 

 After collecting the routine hexavalent chromium sample, the samplers dropped EPA’s 

silicone tubing on the ground. The samplers recovered the tubing from the ground, but the end of 

tubing was contaminated. The sampling team removed the connector piece on the end of the 

tubing and used Homer City’s representatives’ tubing to pour sample over the end of EPA’s 

tubing for two minutes. EPA did not replace the sample tubing, but rather continued to use the 

tubing for the remainder of the sample collection. 

 After collecting all the dissolved metals samples, the sampling team removed the capsule 

filter from the tubing configuration, and purged the tubing for one minute. The samplers then 

collected the low-level total metals, low-level total mercury, low-level dissolved mercury, 

routine total metals, and arsenic/selenium speciation samples in a “cleanbox,” as described in 

Section 3.1. The sampling team then collected the BOD, Group I, and Group II samples by 

pouring the samples directly from the tubing into the samples bottles without using a “cleanbox.” 

To collect the HEM/SGT-HEM samples, the samplers dipped the sample bottles directly into the 

overflow weir to prevent any oil and grease adhering to the sides of the tubing. Therefore, EPA 
3-6 

did not collect split samples with Homer City’s representative for the HEM/SGT-HEM samples, 

but instead, collected duplicate samples with Homer City’s representative. 

 During the sample collection, the sampling team collected an aliquot of sample for field 

testing. Sample pH and temperature were measured immediately at the sampling point using a 

pH meter and four-color pH paper. The four-color pH paper was used as an independent check of 

the pH meter to ensure that similar results were measured. After returning to the staging area, the 

sampling team took measurements of free and total residual chlorine using a colorimeter. Table 

3-3 presents the field measurement data for the second-stage clarifier overflow in the FGD 

wastewater treatment system. 

3.1.3 Effluent from FGD Wastewater Treatment 

 The effluent from the FGD wastewater treatment system (SP-3) was collected directly 

from the effluent tank. Figure 2-1 identifies the sampling location for SP-3. This sample was 

collected as a grab sample, because all the wastewater entering the effluent tank has been treated 

in the FGD wastewater treatment system and is discharged from the tank; therefore, the 

wastewater characteristics should be fairly homogeneous. The sampling point was located inside, 

next to the staging area; therefore, there were no wind or rain concerns during the sample 

collection. 

 Prior to collecting samples at the effluent from the FGD wastewater treatment system 

(SP-3), the sampling team collected field blanks (SP-8) for low-level total mercury, low-level 

total metals, routine total metals, low-level dissolved metals, low-level hexavalent chromium, 

routine dissolved metals, and routine hexavalent chromium. See Section 5.2.3 for a description 

of the field blank sample collection at the effluent from the FGD wastewater treatment system. 

 EPA collected the wastewater samples for the effluent from the FGD wastewater 

treatment system by pumping samples from the effluent tank into the sample containers. The 

sampling team attached one end of a 25-foot length of Teflon® tubing to a piece of PVC pipe 

and inserted the PVC pipe tubing into the effluent tank through a hole in the top of the tank. The 

sampling team positioned the tubing to reach the sampling team at the staging area and attached 

it to a piece of silicone tubing, which was threaded through an ISCO peristaltic pump. The 

sampling team attached a “Y” splitter to the other end of the silicone tubing, with two additional 

pieces of silicone tubing attached to the “Y” splitter. The length of silicone tubing between the 

pump and the “Y” splitter consisted of two pieces with a small connector, which allowed EPA to 

attach and detach a capsule filter inline with the tubing configuration. The “Y” splitter allowed 

EPA to collect “true” split samples with Homer City’s representative. Figures D-6 and D-7, in 

Appendix D, present pictures of the sampling set up for the effluent from the FGD wastewater 

treatment system. 

 After EPA configured the tubing for the sampling point, the samplers purged the tubing 

and filter with sample for approximately one minute. The samplers first collected the low-level 

dissolved metals sample, as well as the QC and duplicate samples because the capsule filter was 

already inline with the tubing configuration from the dissolved metals field blank sample 

collection. The sampling team then installed a new capsule filter and purged the filter with 

approximately one-half liter of sample. After purging the filter, the samplers collected the lowlevel hexavalent chromium, routine dissolved metals, and the routine hexavalent chromium 
3-7 

samples, as well as the QC and duplicate samples for each analyte. Each of these samples was 

collected in a “cleanbox,” as described in Section 3.1. 

 After collecting all the dissolved metals samples, the sampling team removed the capsule 

filter from the tubing configuration, and purged the tubing for one minute. The samplers then 

collected the low-level total metals, low-level total mercury, low-level dissolved mercury, 

routine total metals, and arsenic/selenium speciation samples, as well as the QC and duplicate 

samples for each analyte in a “cleanbox,” as described in Section 3.1. The sampling team then 

collected the BOD, Group I, and Group II samples, as well as the QC and duplicate samples for 

each analyte, by pouring the samples directly from the tubing into the samples bottles without 

using a “cleanbox.” To aid in the collection of the HEM/SGT-HEM samples, Homer City 

installed a stainless steel tap off of the effluent tank to allow EPA to collect samples without 

using tubing. The samplers flushed the stainless steel tap for four minutes, because the initial 20 

seconds of sample from the tap appeared to contain high solids, but by the end of the four 

minutes, the sample looked similar to the effluent collected for the other samples. EPA then 

collected the HEM/SGT-HEM samples directly from the stainless steel sample tap to prevent any 

oil and grease adhering to the sides of the tubing. Therefore, EPA did not collect split samples 

with Homer City’s representative for the HEM/SGT-HEM samples, but instead, collected 

duplicate samples with Homer City’s representative. 

 During the sample collection, the sampling team collected an aliquot of sample for field 

testing. Sample pH and temperature were measured immediately at the sampling point using a 

pH meter and four-color pH paper. The four-color pH paper was used as an independent check of 

the pH meter to ensure that similar results were measured. After returning to the staging area, the 

sampling team took measurements of free and total residual chlorine using a colorimeter. Table 

3-3 presents the field measurement data for the effluent from the FGD wastewater treatment 

system. 

3.1.4 Effluent from Bottom Ash Pond 

 EPA collected the effluent from the bottom ash pond (SP-4), from the clear well, which 

receives water from the two bottom ash ponds. Homer City collects its bottom ash effluent 

monitoring samples at the clearwell overflow weir. However, EPA collected samples from the 

middle area of the clear well, away from the skimmer and overflow weir, which were rusty and 

had the potential to contaminate the samples with metal. Figure D-8, in Appendix D, shows the 

sampling point location upstream of the skimmer. EPA felt that the sampling point selected, 

although prior to the skimmer and weir, still represented the effluent from a bottom ash pond. 

The sample was collected as a grab sample because the residence time of the ash ponds and the 

clear well equalize the wastewater discharges. 

 The sampling point for the effluent from the bottom ash pond was located outside near 

the clear well. At the time the sampling team went out to the sampling point, a vacuum truck was 

skimming solids from the surface of the clear well. According to the truck operator, the 

skimming had started approximately two hours before the samplers arrived at the sampling point. 

After approximately 10 minutes, the vacuum truck left the sampling area. At the time the truck 

finished skimming, Unit 3 was sluicing the bottom ash to the ash ponds. Because the plant uses 

water from the clear well as the source for bottom ash sluice water, water was being removed 

from the clear well, and therefore, the plant was not discharging. The sampling team waited 
3-8 

approximately one hour before setting up the sampling point so that none of the three units were 

sluicing bottom ash and the plant was discharging from the clear well. 

 Prior to collecting samples at the effluent from the bottom ash pond (SP-4), the sampling 

team collected field blanks (SP-9) for low-level total mercury, low-level total metals, routine 

total metals, low-level dissolved metals, low-level hexavalent chromium, routine dissolved 

metals, and routine hexavalent chromium. See Section 5.2.3 for a description of the field blank 

sample collection at the effluent from the bottom ash pond. 

 EPA collected the wastewater samples for the effluent from the bottom ash pond by 

pumping samples from the clear well into the sample containers. EPA attached one end of a 25-

foot length of Teflon® tubing to a piece of PVC pipe and inserted the tubing into the clear well 

at a point where there was no residue floating on the top of the water. The sampling team secured 

the PVC pipe along a rail, so that the tubing was approximately two feet below the surface of the 

water (the clearwell has a depth of 18 feet). The sampling team positioned the tubing to reach 

the set-up location near the clear well and attached it to a piece of silicone tubing, which was 

threaded through an ISCO peristaltic pump. The sampling team attached a “Y” splitter to the end 

of the silicone tubing, with two additional pieces of silicone tubing attached to the “Y” splitter. 

The length of silicone tubing between the pump and the “Y” splitter consisted of two pieces with 

a small connector, which allowed EPA to attach and detach a capsule filter inline with the tubing 

configuration. The “Y” splitter allowed EPA to collect “true” split samples with Homer City’s 

representative. Figure D-8, in Appendix D, presents a picture of the sampling set up for the 

effluent from the bottom ash pond. 

 After EPA configured the tubing for the sampling point, the samplers purged the tubing 

and filter with sample for approximately 1.5 minutes. The samplers first collected the low-level 

dissolved metals sample and the QC sample because the capsule filter was already inline with the 

tubing configuration from the dissolved metals field blank sample collection. The sampling team 

then installed a new capsule filter and purged the filter with sample for one minute. After 

purging the filter, the samplers collected the low-level hexavalent chromium, routine dissolved 

metals, the routine hexavalent chromium samples, and the QC sample for each analyte. Each of 

these samples was collected in a “cleanbox”, as described in Section 3.1. 

 After collecting all the dissolved metals samples, the sampling team removed the capsule 

filter from the tubing configuration, and purged the tubing for one minute. The samplers then 

collected the low-level total metals, low-level total mercury, low-level dissolved mercury, 

routine total metals, as well as the QC sample for each analyte, and arsenic/selenium speciation 

samples in a “cleanbox,” as described in Section 3.1. The sampling team then collected the BOD, 

Group I, and Group II samples, as well as the QC sample for each analyte, by pouring the 

samples directly from the tubing into the samples bottles without using a “cleanbox.” The 

samplers collected the HEM/SGT-HEM and HEM/SGT-HEM QC samples by using a bottle 

dipper to collect the samples directly from the clear well to prevent any oil and grease adhering 

to the sides of the tubing. Therefore, EPA did not collect split samples with Homer City’s 

representative for the HEM/SGT-HEM samples, but instead, collected duplicate samples with 

Homer City’s representative. The samplers collected the HEM/SGT-HEM samples as close to 

the location where the tubing had been collecting the other samples as possible. 
3-9 

 During the sample collection, the sampling team collected an aliquot of sample for field 

testing. Sample pH and temperature were measured immediately at the sampling point using a 

pH meter and four-color pH paper. The four-color pH paper was used as an independent check of 

the pH meter to ensure that similar results were measured. After returning to the staging area, the 

sampling team took measurements of free and total residual chlorine using a colorimeter. Table 

3-3 presents the field measurement data for the effluent from the bottom ash pond. 

3.2 List of Analytes and Sample Preservation

 Analytes in EPA’s Homer City sampling episode included those in the following classes 

of pollutants: 

• Classicals: 

— Biochemical oxygen demand, 5-day (BOD5), 

— Total suspended solids (TSS), 

— Total dissolved solids (TDS), 

— Sulfate, 

— Chloride, 

— Total Kjeldahl nitrogen (TKN), 

— Ammonia as nitrogen, 

— Nitrate/nitrite as nitrogen, 

— Total phosphorus, 

— Hexane extractable material (HEM), and 

— Silica-gel treated hexane extractable material (SGT-HEM); and 

• Metals: 

— Routine total metals (27 metals: aluminum, antimony, arsenic, barium, 

beryllium, boron, cadmium, calcium, chromium, cobalt, copper, iron, lead, 

magnesium, manganese, mercury, molybdenum, nickel, selenium, silver, 

sodium, thallium, tin, titanium, vanadium, yttrium, and zinc), 

— Routine dissolved metals (27 metals), 

— Routine hexavalent chromium, 

— Low-level total mercury, 

— Low-level dissolved mercury, 

— Low-level hexavalent chromium, 

— Low-level total metals (11 metals: antimony, arsenic, cadmium, 

chromium, copper, lead, nickel, selenium, silver, thallium, zinc), and 

— Low-level dissolved metals (11 metals). 

 The analytes selected reflect the current understanding of coal-fired power plant air 

pollution control wastewaters, including contributions from coal, scrubber sorbents, treatment 

chemicals, and other sources. Table 3-4 lists the analytical methods used to determine pollutant 

concentrations. 

 Table 3-5 lists the containers used for sample collection as well as the preservation 

requirements for each sample, and Table 3-6 summarizes the chemical preservation for each of 

the samples that were preserved on site. The sampling team preserved samples in accordance 

with procedures described in Section 3.4 of the Sampling Plan. All samples except routine total 

and dissolved metals, low-level total and dissolved metals, low-level total and dissolved 
3-10 

mercury, and low-level hexavalent chromium samples were placed on ice and cooled to <6°C 

immediately following collection. All dissolved metals samples, except low-level dissolved 

mercury, were filtered in the field. The routine and low-level hexavalent chromium samples were 

preserved in the field, but all other metals samples were acid-preserved at the laboratory, prior to 

extraction. The routine hexavalent chromium samples were supposed to be preserved to a pH 

between 9.3 and 9.7 using an ammonium sulfate buffer solution; however, the sampling team 

discontinued preservation for some samples because 10 percent of the sample volume was added 

before the required pH was achieved (the pH of these preserved samples was approximately 9.0). 

The low-level hexavalent chromium sample bottles were prepreserved with 4 mL of 50-percent 

NaOH. The Group II and HEM/SGT-HEM samples were preserved with sulfur acid to a pH of 

<2 immediately after collection in the staging area, and the pH was confirmed with four-color pH 

strips. 

3.3 Plant Operational Data

 During the sampling episode at Homer City, plant personnel provided the sampling team 

with operational data for each of the generating units, the FGD scrubber system, and the bottom 

ash collection system, as well as operational and flow data for the FGD wastewater treatment 

system. Table 3-7 presents the unit operating characteristics, Table 3-8 presents the FGD 

scrubber system operating characteristics, Table 3-9 presents the FGD wastewater treatment 

system operating characteristics, and Table 3-10 presents the bottom ash system operating 

characteristics during the sampling episode. 

3.4 Deviations from the Sampling and Analysis Plan

 The sampling episode proceeded as specified in the Sampling Plan with the exceptions 

described below: 

• Collection Containers for Dissolved Metals at SP-1. For the influent to the 

FGD wastewater treatment system, EPA planned to collect volume for the pumpoff of routine and low-level dissolved metals and routine hexavalent chromium 

samples, as well as the QC samples, into two precleaned 10-liter containers. 

However, EPA collected the volume into three precleaned 10-liter container, to 

ensure that enough volume was collected. 

• Dissolved Metals Sample Filtration Time at SP-1. For the influent to the FGD 

wastewater treatment system, EPA planned to filter the dissolved metals samples 

approximately one hour after filling the 10-liter containers with sample; however, 

the filtration did not occur until approximately 2.5 hours later. 

• Dissolved Metals Sample Collection at all Sampling Points. EPA planned to 

collect the dissolved metals samples at all sampling points as “multipour” splits, 

by partially filling the EPA bottle, then filling the split bottle, and then repeating 

the partial filling of both bottles two more times until both bottles are completely 

full. Instead, EPA collected “true” split samples with Homer City’s representative 

at all sampling points by placing a filter directly after the peristaltic pump and 

then having a splitter after the filter. 
3-11 

• Low-Level Total Mercury Field Blank Sample Collection at all Sampling 

Points. EPA planned to collect the low-level total mercury field blank samples 

after the low-level total metals field blank samples at all sampling points; 

however, EPA decided to collect the low-level total mercury field blank samples 

first. The low-level total metals field blank water was held in a plastic container, 

while the low-level mercury field blank water was held in a borosilicate glass 

container (because the glass is easier to clean for mercury contamination). The 

borosilicate glass has the potential to leach into the mercury field blank water, and 

therefore, could potentially contaminate the samples for the boron analysis. For 

this reason, EPA decided that the low-level total metals field blanks should be 

collected after the low-level mercury field blanks because then the field blank and 

the wastewater sample are both exposed to the same potential boron 

contamination from the low-level total mercury field blank water. 

• Sample Collection at the Second-Stage Clarifier (SP-2). EPA planned to 

collect the samples of the second-stage clarifier overflow by setting up the 

sampling point on the clarifier bridge; however, EPA set up the sampling 

equipment on the ground, at the bottom of the clarifier. One sampler stood on the 

scaffolding set up by Homer City holding the tubing in the clarifier overflow weir. 

• Second-Stage Clarifier Flow Rate Estimation. EPA planned to estimate the 

flow rate of the second-stage clarifier overflow by measuring the time required to 

fill a 1-L jar placed at the overflow weir, if possible. However, EPA decided that 

this flow value would likely not produce a reliable result and that the influent flow 

rate into the treatment system would be a more accurate representation of the flow 

rate. 

• HEM/SGT-HEM Sample Collection at Second-Stage Clarifier. EPA planned 

to collect the HEM/SGT-HEM samples at the second-stage clarifier by using a 

bottle dipper to place the bottle near the overflow weir and filling the bottle with 

the water flowing over the weir. However, because Homer City built the 

scaffolding along the clarifier wall, EPA was able to dip the bottles directly into 

the overflow weir where the water was collected prior to being transported to the 

pH adjustment tank. 

• Sample Collection at the FGD Effluent (SP-3). EPA planned to collect the 

samples of the effluent from the FGD wastewater treatment system by using 

Homer City’s ISCO pump and tubing and attaching new tubing to the end of the 

preexisting tubing. However, EPA decided to use new Teflon® and silicone 

tubing cleaned according to EPA Method 1669 protocols and a rented ISCO pump 

to collect the samples. 

• HEM/SGT-HEM Sample Collection at FGD Effluent. EPA planned to collect 

the HEM/SGT-HEM samples by dipping the bottles directly into the effluent tank 

using a bottle dipper; however, Homer City determined it would be inconvenient 

to remove the top of the effluent tank. Therefore, prior to the sampling episode, 

Homer City installed a stainless steel tap at the bottom of the effluent tank to 

allow EPA to collect samples without the use of tubing. EPA collected the 
3-12 

HEM/SGT-HEM samples at the effluent from the FGD wastewater treatment 

system by filling bottles directly from a stainless steel tap that Homer City had 

installed. 

• Sample Tubing Dropped During Sample Collection. During the collection of 

the influent to the FGD wastewater treatment system (SP-1) and the second-stage 

clarifier overflow in the FGD wastewater treatment system (SP-2), EPA dropped 

the sample tubing on the ground. For the influent sample, EPA replaced the 

tubing with an identical piece of pre-cleaned tubing and resumed sample 

collection. For the second-stage clarifier overflow sample, EPA removed the 

connector on the end of the sample tubing and rinsed the tubing for 2 minutes 

with sample, prior to resuming sample collection. 

• Sample Tubing Detached During Sample Collection at SP-2. While purging 

the sample tubing at the second-stage clarifier overflow in the FGD wastewater 

treatment system (SP-2), the tubing detached from the filter due to backpressure. 

The samplers were able to recover the filter and tubing without contaminating any 

equipment. The samplers reattached the tubing to the filter and continued purging 

for two minutes. 

• Chlorine Field Test Measurements. EPA did not perform the chlorine field test 

measurement for the influent to the FGD wastewater treatment system (SP-1) 

immediately after sample collection because the color of the sample would have 

prevented an accurate measurement; therefore, EPA performed the analysis on a 

filtered sample collected during the pump-off. Because this test was performed on 

a filtered sample and because the chlorine may have dissipated during the time 

between initial sample collection and pump-off, the result may not represent the 

actual wastewater characteristics. In addition, EPA was unable to perform the 

chlorine field test measurement for the effluent from the bottom ash pond 

immediately after sample collection. 

• Preservation of Routine Hexavalent Chromium. The routine hexavalent 

chromium samples were supposed to be preserved to a pH between 9.3 and 9.7 

using an ammonium sulfate buffer solution; however, for some of the samples, 

preservation was discontinued because 10 percent of the sample volume was 

added before the required pH was achieved (the pH of these preserved samples 

was approximately 9.0). 
3-13 

Table 3-1. Sample Collection Information, Homer City 

Sampling 

Point Number Sampling Point Description 

Type of 

Sample 

Sample Collection 

Date and Time SCC Number

SP-1 Influent to FGD Wastewater Treatment 

System 

Grab 08/22/2007 

1153 a and 1442 b

70420 

SP-2 Second-Stage Clarifier Overflow in FGD 

Wastewater Treatment System 

Grab 08/23/2007 

0750 

70421 

SP-3 Effluent from FGD Wastewater Treatment 

System 

Grab 08/22/2007 

0813 

70422 

SP-4 Effluent from Bottom Ash Pond Grab 08/23/2007 

1130 

70423 

SP-5 Duplicate of Effluent from FGD 

Wastewater Treatment System 

Grab 08/22/2007 

0813 

70424 

SP-6 Influent to FGD Wastewater Treatment 

System Field Blank 

Grab 08/22/2007 

1127 a

 and 1430 b

70425 

SP-7 Second-Stage Clarifier Overflow in FGD 

Wastewater Treatment System Field 

Blank 

Grab 08/23/2007 

0718 

70426 

SP-8 Effluent from FGD Wastewater Treatment 

System Field Blank 

Grab 08/22/2007 

0731 

70427 

SP-9 Effluent from Bottom Ash Pond Field 

Blank 

Grab 08/23/2007 

1102 

70428 

a – Collection of the total metals samples (low-level and routine), low-level dissolved mercury, and classicals. 

b – Collection of the dissolved metals samples (except low-level dissolved mercury). 
3-14 

Table 3-2. Number of Samples Collected by Sampling Point, Homer City 

Sampling 

Point 

Number Sampling Point Description 

Low-Level Total Metals (11 

analytes) 

Low-Level Dissolved Metals 

(11 analytes) 

Low-Level Total Mercury 

Low-Level Dissolved 

Mercury 

Low-Level Hexavalent 

Chromium 

Routine Total Metals (27 

analytes) 

Routine Dissolved Metals 

(27 analytes) 

BOD

5 

Group I 

a

 

Group II 

b

SP-1 Influent to FGD Wastewater 

Treatment System 

1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1 1 1 

SP-2 Second-Stage Clarifier Overflow in 

FGD Wastewater Treatment System 

1 1 1 1 1 1 1 1 1 1 

SP-3 Effluent from FGD Wastewater 

Treatment System 

1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 

SP-4 Bottom Ash Pond Effluent 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC 1+QC SP-5 Duplicate of Effluent from FGD 

Wastewater Treatment System 

1 1 1 1 1 1 1 1 1 1 

SP-6 Influent to FGD Wastewater 

Treatment System Field Blank 

1 1 1 

SP-7 Second-Stage Clarifier Overflow in 

FGD Wastewater Treatment System Field Blank 

1 1 1 1 1 1 

SP-8 Effluent from FGD Wastewater 

Treatment System Field Blank 

1 1 1 1 1 1 

SP-9 Bottom Ash Pond Effluent Field 

Blank 

1 1 1 1 1 1 

Total Number of Samples 9+3QC 9+3QC 9+3QC 5+3QC 7+2QC 8+3QC 8+3QC 5+2QC 5+2QC 5+2QC 

a – Group I includes total suspended solids (TSS), total dissolved solids (TDS), sulfate and chloride. b – Group II includes ammonia as nitrogen, nitrate/nitrite as nitrogen, total Kjeldahl nitrogen (TKN), and total phosphorus. 

c – The selenium/arsenic speciation results from the sampling episode were not available at the time this report was finalized and therefore are not inc
3-15 

Table 3-3. Field Measurements, Homer City 

pH 

(S.U.) Sampling Point 

Number 

Sampling Point 

Description 

Date and 

Time 

Temp 

°C 

Meter Meter a Strips 

Free Chlorine 

(mg/L) 

Total Chlorine 

(mg/L) 

M

Int

R

SP-1 Influent to FGD 

Wastewater Treatment 

08/22/07 

1249 

38.2 6.78 NA 0.00 b 0.00 b 

SP-2 Second-Stage Clarifier 

Overflow in FGD Wastewater Treatment System 

08/23/07 

0823 

32.8 8.09 8.5 0.00 d 0.00 d 

SP-3 Effluent from FGD 

Wastewater Treatment 

08/22/07 

0921 

29.4 7.37 7 0.33 0.33 

SP-4 Bottom Ash Pond Effluent 08/23/07 

1207 

37.8 8.46 NA 0.00 f 0.00 f 

a – The pH meter was calibrated on the morning of August 22 and 23, 2007 using pre-packaged buffer solutions at pHs 4.0, 7.0, and 10b – EPA did not initially perform a free and total chlorine measurement because the color of the sample would prevent an accurate cololater performed a reading of the filtered sample after settling, which resulted in 0.00 mg/L for both free and total chlorine. 

c – Flow rate based on one measurement recorded from the influent flow meter during sample collection at 1:11 PM on August 22, 200d – The free and total chlorine measurements were 0.00 mg/L; however, the samplers observed that the sample looked cloudy after the 

phenylenediamine (DPD) reagent addition (as compared to the colorless sample prior to reagent addition). e – Flow rate based on the average of 12 measurements recorded from the effluent flow meter during sample collection on August 22, 2NA – Not analyzed. f – EPA performed the free and total chlorine measurements at 5:00 pm; therefore, the chlorine in the sample may have dissipated. 
3-16

Table 3-4. Analytical Methods and Procedures for Samples Collected at Homer City 

Method Number Parameter Method Type 

Classicals 

SM 5210 B Biochemical Oxygen Demand (BOD5) Probe 

SM 2540 D Total Suspended Solids (TSS) Gravimetric 

SM 2540 C Total Dissolved Solids (TDS) Gravimetric 

ASTM D516-90 Sulfate Turbidimetric 

SM 4500–Cl–C Chloride Titrimetric, mercuric 

nitrate 

SM 4500—NH3 F 

(18th ed.) 

Ammonia as Nitrogen Distillation, 

potentiometric 

SM 4500—NO3 -H Nitrate/Nitrate as Nitrogen Autoanalyzer 

SM 4500—N,C 

(18th ed.) 

Total Kjeldahl Nitrogen (TKN) Digestion, distillation, 

potentiometric 

EPA 365.3 (Rev 1978) Total Phosphorus Digestion, 

spectrophotometric 

EPA 1664A Hexane Extractable Material (HEM) Gravimetric 

EPA 1664A Silica Gel Treated Hexane Extractable Material (SGT-HEM) Gravimetric 

Metals 

EPA 1631 Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor 

Atomic Fluorescence Spectrometry 

Oxidation, Purge and 

Trap, and CVAFS 

EPA 1636 Determination of Hexavalent Chromium by Ion Chromatography Ion Chromatography 

EPA 1638 Determination of Trace Elements in Ambient Waters by 

Inductively Coupled Plasma – Mass Spectroscopy (includes 

antimony, arsenic, cadmium, chromium, copper, lead, nickel, 

selenium, silver, thallium, and zinc) 

ICP/MS 

EPA 200.7, 245.1 Metals by Inductively Coupled Plasma Atomic Emission 

Spectrometry, and Atomic Absorption Spectroscopy 

ICP and CVAA 

ASTM D1687-92 Hexavalent Chromium Colorimetric 

CVAFS – Cold vapor atomic fluorescence spectrometry. 

ICP/MS – Inductively coupled plasma with mass spectrometry. 

ICP – Inductively coupled plasma. 

CVAA – Cold vapor atomic adsorption. 
3-17

Table 3-5. Summary of Sample Container and Planned Preservation 

Parameter Sample Container and Volume On-Site Preservation 

Classicals 

BOD5 One 1-L plastic bottle ≤6oC 

Group I a Two 1-L plastic bottles ≤6EC 

Group II b Two 1-L plastic bottles H2SO4 to pH <2, ≤6EC 

HEM/SGT-HEM Two 1-L wide mouth glass jars H2SO4 to pH <2, ≤6oC 

Metals 

Routine total metals, 27 element 

quantitation (Method 200.7, 200.8, 

200.9, 245.1) 

One 500-mL plastic bottle None 

(acid preserve at laboratory) 

Routine dissolved metals, 27 element 

quantitation (Method 200.7, 200.8, 

200.9, 245.1) 

One 500-mL plastic bottle 0.45 μm filter (performed in field) 

(acid preserve at laboratory) 

Routine hexavalent chromium One 250-mL plastic bottle 0.45 μm filter (performed in field) 

Ammonium sulfate buffer to pH 9.3 

– 9.7, ≤6EC 

Low-level total mercury (Method 1631) Two 250-mL glasses (ultraclean), 

fluoropolymer lined caps 

None 

(acid preserve at laboratory) 

Low-level dissolved mercury (Method 

1631) 

Two 250-mL glasses (ultraclean), 

fluoropolymer lined caps 

None 

(acid preserve and filter at 

laboratory) 

Low-level total elements by ICP/MS (11 

elements, Method 1638) 

One 1-L LDPE (ultraclean), 

fluoropolymer lined caps 

None 

(acid preserve at laboratory) 

Low-level dissolved elements by 

ICP/MS (11 elements, Method 1638) 

One 1-L LDPE (ultraclean), 

fluoropolymer lined caps 

0.45 μm filter (performed in field) 

(acid preserve at laboratory) 

Low-level hexavalent chromium 

(Method 1636) 

One 500-mL LDPE (ultraclean), 

fluoropolymer lined caps 

0.45 μm filter (performed in field) 

4 mL 50% NaOH per 500 mL 

sample (performed in field) c 

Selenium/arsenic speciation Two 125-mL amber glasses 

(ultraclean) 

None for original sample, ≤6EC 

Duplicate: HCl to pH <2, ≤6EC 

a – Group I includes TSS, TDS, sulfate, and chloride. 

b – Group II includes ammonia as nitrogen, nitrate/nitrite as nitrogen, TKN, and total phosphorus. 

c – Method 1636 has a preservation requirement that the low-level hexavalent chromium sample be cooled to ≤6EC; 

however, EPA did not cool the low-level hexavalent chromium samples due to contamination concerns. 
a – Preservation of this sample was stopped due to excessive buffering of the sample. The pH of the sample was not 

changing with the addition of the ammonium sulfate buffer solution; therefore, the preservation was stopped to 

prevent the sample from being diluted by the preservative. 

b – The sample bottle was filled too full to preserve initially; therefore, EPA removed some excess volume with a 

pipet prior to preserving the sample. The bottle was shaken well prior to removing the excess volume. 

3-18 

Table 3-6. Sample Preservation Summary, Homer City 

Sampling 

Point 

Number Analysis 

Date and 

Time Chemical 

Initial 

pH 

Final 

pH Amount Added

70420 Group II V1 08/22/07 H2SO4 7 2 50 drops 

70420 Group II V2 08/22/07 H2SO4 7 2 50 drops 

70420 HEM/SGT-HEM V1 08/22/07 H2SO4 7 2 65 drops 

70420 HEM/SGT-HEM V2 08/22/07 H2SO4 7 2 65 drops 

70420 Routine Hexavalent 

Chromium 

08/22/07 Ammonium 

Sulfate Buffer 

7 9 250 drops a

70420 Arsenic/Selenium 

Speciation (Duplicate) 

08/22/07 HCl 7 2 15 drops 

70421 Group II V1 08/23/07 H2SO4 8.5 2 50 drops 

70421 Group II V2 08/23/07 H2SO4 8.5 2 50 drops 

70421 HEM/SGT-HEM V1 08/23/07 H2SO4 8.5 2 70 drops 

70421 HEM/SGT-HEM V2 08/23/07 H2SO4 8.5 2 70 drops 

70421 Routine Hexavalent 

Chromium 

08/23/07 Ammonium 

Sulfate Buffer 

8.5 9.5 250 drops 

70421 Arsenic/Selenium 

Speciation (Duplicate) 

08/23/07 HCl 8.5 2 30 drops 

70422 Group II V1 08/22/07 H2SO4 7 2 60 drops 

70422 Group II V2 08/22/07 H2SO4 7 2 60 drops 

70422 Group II V1 MS/MSD 08/22/07 H2SO4 7 2 60 drops 

70422 Group II V2 MS/MSD 08/22/07 H2SO4 7 2 60 drops 

70422 HEM/SGT-HEM V1 08/22/07 H2SO4 7 2 100 drops 

70422 HEM/SGT-HEM V2 08/22/07 H2SO4 7 2 100 drops 

70422 HEM/SGT-HEM V1 

MS/MSD 

08/22/07 H2SO4 7 2 100 drops 

70422 HEM/SGT-HEM V2 

MS/MSD 

08/22/07 H2SO4 7 2 100 drops 

70422 Routine Hexavalent 

Chromium 

08/22/07 Ammonium 

Sulfate Buffer 

7 9 250 drops b

70422 Routine Hexavalent 

Chromium MS/MSD 

08/22/07 Ammonium 

Sulfate Buffer 

7 9 250 drops b

70422 Arsenic/Selenium 

Speciation (Duplicate) 

08/22/07 HCl 7 2 20 drops 

70423 Group II V1 08/23/07 H2SO4 6.5 2 50 drops 

70423 Group II V2 08/23/07 H2SO4 6.5 2 50 drops 

70423 Group II V1 MS/MSD 08/23/07 H2SO4 6.5 2 50 drops 

70423 Group II V2 MS/MSD 08/23/07 H2SO4 6.5 2 50 drops 

70423 HEM/SGT-HEM V1 08/23/07 H2SO4 6.5 2 80 drops 
a – Preservation of this sample was stopped due to excessive buffering of the sample. The pH of the sample was not 

changing with the addition of the ammonium sulfate buffer solution; therefore, the preservation was stopped to 

prevent the sample from being diluted by the preservative. 

b – The sample bottle was filled too full to preserve initially; therefore, EPA removed some excess volume with a 

pipet prior to preserving the sample. The bottle was shaken well prior to removing the excess volume. 

3-19 

Table 3-6. Sample Preservation Summary, Homer City 

Sampling 

Point 

Number Analysis 

Date and 

Time Chemical 

Initial 

pH 

Final 

pH Amount Added

70423 HEM/SGT-HEM V2 08/23/07 H2SO4 6.5 2 80 drops 

70423 HEM/SGT-HEM V1 08/23/07 H2SO4 6.5 2 90 drops 

70423 HEM/SGT-HEM V2 08/23/07 H2SO4 6.5 2 90 drops 

70423 Routine Hexavalent 

Chromium 

08/23/07 Ammonium 

Sulfate Buffer 

6.5 9.5 250 drops 

70423 Routine Hexavalent 

Chromium MS/MSD 

08/23/07 Ammonium 

Sulfate Buffer 

6.5 9.5 250 drops 

70423 Arsenic/Selenium 

Speciation (Duplicate) 

08/22/07 HCl 5.5 2 20 drops 

70424 Group II V1 (Duplicate) 08/22/07 H2SO4 7 2 60 drops 

70424 Group II V2 (Duplicate) 08/22/07 H2SO4 7 2 60 drops 

70424 Routine Hexavalent 

Chromium (Duplicate) 

08/22/07 Ammonium 

Sulfate Buffer 

7 9 250 drops b

70426 Routine Hexavalent 

Chromium (Field Blank) 

08/23/07 Ammonium 

Sulfate Buffer 

7 9.5 80 drops 

70427 Routine Hexavalent 

Chromium (Field Blank) 

08/22/07 Ammonium 

Sulfate Buffer 

7 9.5 90 drops 

70428 Routine Hexavalent 

Chromium (Field Blank) 

08/23/07 Ammonium 

Sulfate Buffer 

7 9.5 140 drops 
3-20 

Table 3-7. Generating Unit Operating Characteristics During Sample Collection, Homer 

Unit 

ID Boiler Type Coal type 

Coal 

Usage 

(tons) a

Source of Coal 

(coal region 

and/or state) 

Capacity 

(MW) 

Electricity 

Production (or 

percent 

capacity) 

SCR 

(No, On, 

Off) 

Particul

Control Sy

(HS/CS ES

BH) 

1 Supercritical 

wall fired boiler 

Eastern Bituminous blend 

11,429 See note below. 650 646 (99%) SCR on. ESP 

2 Supercritical 

wall fired boiler 

Eastern Bituminous blend 

10,939 See note below. 650 618 (95%) SCR on. ESP 

3 Babcock & 

Wilson drum boiler 

Eastern Bituminous blend 

12,097 See note below. 700 675 (96%) SCR on. ESP 

Note: Homer City was burning an Eastern Bituminous blend of mostly coal from the upper and lower Freeport seam and the upper, miseam. In addition a lesser amount of coal from the Pittsburgh seam is also used. a – Total amount of coal burned in the units from 12 AM 8/22/07 through 11 PM 8/23/07 (48 hours average). 

Table 3-8. FGD Scrubber System Operating Characteristics, Homer City 

Unit ID 

Type of 

Scrubber Sorbent 

Additives 

(DBA, Formic 

Acid, etc.) 

FGD Make-up Water 

Source 

SO2 Removal 

Percentage 

(%) 

Forced 

Oxidation

(Yes/No) 

Percent S

in Slur

(%) 

3 Spray tray Limestone Formic Acid Open cycle using 

clarified river water and cooling water blowdown from unit 3 only. 

Typically 95-98% 

95.4% Average for 

8/22-23 

Yes Typical

13-15% 

a – The solids concentration in the scrubber purge, after the primary and secondary hydroclones, during the sampling episode was 9,900 21,700 mg/L on 8/23/07. 
3-21

Table 3-9. FGD Wastewater Treatment System Operating Characteristics, Homer City 

FGD Solids Dewatering (for last cycle prior to sampling or while sampling) 

Scrubber slurry blowdown flow rate 1444 gpm 

Scrubber slurry blowdown duration 12 - 13 hours 

Scrubber slurry blowdown percent solids 16 percent to 13 percent (start to finish) 

FGD Wastewater Treatment System Operation During Sample Collection 

Scrubber purge flow rate 230 gpm 

Scrubber purge duration 12 – 13 hours 

Lime addition 2.78 gpm for pH of 8.1 

Ferric chloride addition 63 ppm (set-point in first-stage neutralization tank) 

60 ppm (set-point in second-stage neutralization tank) 

Anionic Polymer (Nalco Pol-E-Z 2706) addition 14 ppm (set-point in first-stage clarifier) 

6.5 ppm (set-point in second-stage clarifier) 

Cationic Polymer (Nalcolyte 8100) addition 20 ppm (set-point in first stage neutralization tank) 

Hydrochloric acid addition Not used during sampling episode 

Effluent flow rate (average) 110 gpm 

Frequency of effluent discharge Continuous 

Retention time of first-stage neutralization tank 38 minutes 

Retention time of first-stage clarifier 60 minutes 

Retention time of second-stage neutralization tank 38 minutes 

Retention time of second-stage clarifier 60 minutes 

Note: Data regarding the FGD solids dewatering frequency were not provided by Homer City. 

Table 3-10. Bottom Ash System Operating Characteristics, Homer City 

Unit ID 

Bottom Ash 

Generation (tph) 

Bottom Ash Sluice 

Water Flow Rate 

(gph) 

Source of Bottom 

Ash Sluice Water

Sluice Cycle 

Duration and 

Frequency 

Continuous 

Sluicing (Yes/No)

1 8.09 168,000 Units 1, 2, and 3 

circulation water 

cooling towers. 

90 minutes each 12 

hour shift 

No 

2 8.09 168,000 Units 1, 2, and 3 

circulation water 

cooling towers. 

90 minutes each 12 

hour shift 

No 

3 4.62 168,000 Units 1, 2, and 3 

circulation water 

cooling towers. 

45 minutes each 12 

hour shift 

No 
4-1 

4. LABORATORY ANALYTICAL RESULTS AND DISCUSSION

 This section summarizes and discusses the analytical data collected during this sampling 

episode. Section 4.1 discusses the methods used by the laboratories for the biphasic analysis of 

SP-1 and presents the results of the analyses. Section 4.2 presents the laboratory analytical data 

for the influent to and effluent from the FGD wastewater treatment system, as well as the 

second-stage clarifier overflow within the system. Section 4.3 presents the laboratory analytical 

data for the effluent from the bottom ash pond. 

 Appendix A provides all analytical results for all samples collected at Homer City, 

including all qualified results and all results that were measured above the method detection 

limit, but below the reporting limit (i.e., J-values). Appendix B presents the analytical results in a 

format similar to that used in Sections 4.2 and 4.3, but with the J-values shown (J-values are not 

included in the tables presented in Sections 4.2 and 4.3). 

4.1 Measured and Calculated Results for FGD Influent Samples

 The samples of the influent to the FGD wastewater treatment system were expected to 

contain significant amounts of readily settleable solids, to a large degree consisting of gypsum, 

unreacted limestone, and fly ash. Because of this, EPA was concerned that there could be 

analytical interferences for the metals analyses, since the acid digestion procedures used may not 

be sufficiently rigorous for samples with high solids loads. Therefore, EPA directed its contract 

laboratories to separate the aqueous and solid phases of the sample prior to conducting certain 

analyses, where allowed by the analytical method and if necessary to obtain acceptable analytical 

results. This biphasic approach provides EPA with both measured and calculated pollutant 

concentrations for the following phases of the sample: 

• Aqueous phase; 

• Solid phase; and 

• Total sample. 

The routine metals laboratory, ProChem Analytical (ProChem), and the low-level laboratory, 

Battelle Marine Sciences Laboratory (Battelle), used two different approaches for the biphasic 

analysis because of the different methods used for routine versus low-level metals analyses. This 

section describes the approaches used by each laboratory and presents the results of the analyses. 

Routine Metals and Selected Classicals Analyses 

 ProChem used EPA Method 200.7 to analyze the wastewater samples for routine metals, 

and EPA Method 245.1 to analyze for routine mercury. EPA Method 200.7 states, “Aqueous 

samples containing total suspended solids ≥1% (w/v) should be extracted as a solid type 

sample.” [4] Because EPA expected the solids content to be greater than one percent, ProChem 

developed an approach for the analysis of the FGD influent samples that consisted of filtering the 

solids from the sample and analyzing the solid and aqueous phases separately. To calculate the 

total sample concentration from the solid and aqueous phase results, the laboratory also needed 

to measure the original sample volume, solid phase weight, and filtrate volume. EPA developed 

the following equation to calculate the individual metal total concentrations for the sample. 
4-2 

Sample

Filtrate Filtrate Solid Solid

V

(C V ) (C Wt ) Total SampleConcentration × + × = (4-1) 

where: 

CFiltrate = concentration of the analyte in the aqueous phase of the sample; 

VFiltrate = volume of the filtrate; 

CSolid = concentration of the analyte in the solid phase of the sample; 

WtSolid = weight of the solids in the sample; and 

VSample = volume of the original sample. 

ProChem used the same approach for the six classical pollutants that were analyzed as biphasic 

samples: ammonia as nitrogen, chloride, nitrate/nitrite, sulfate, total Kjeldahl nitrogen (TKN), 

and total phosphorus. 

Low-Level Metals Analyses 

 Battelle used EPA Method 1638 to analyze the wastewater samples for low-level metals, 

and EPA Method 1631E to analyze for low-level mercury. EPA Method 1638 does not contain 

any language stating how wastewater samples with high solid concentrations should be analyzed; 

therefore, Battelle developed an approach for the analysis of the FGD influent samples that 

minimized potential contamination to the samples. Battelle’s approach consisted of analyzing the 

total metals concentration and dissolved metals concentration for each analyte directly from the 

sample bottles, and calculating the solid phase concentration. By using this approach, the 

laboratory did not have to perform an extra filtration step to determine the individual metals 

concentrations for the various phases in the sample. Battelle did not have any problems with the 

digestion of the solids during the total sample analyses for the Homer City FGD influent 

samples. 

 To calculate the solid phase concentration from the total and dissolved phase results, 

Battelle also measured the TSS level in the total metals sample bottle. EPA used the following 

equation to calculate the individual metal solid phase concentrations for the sample: 

TSS

Total Diss

Solid C

C - C C = (4-2) 

where: 

CSolid = concentration of the metal in the solid phase of the sample; 

CTotal = total concentration of the metal in the sample; 

CDiss = concentration of the metal in the dissolved phase of the sample; and 

CTSS = TSS concentration of the sample. 

Analytical Deviations 

 During the analysis of the Homer City FGD influent samples, ProChem did not measure 

the original sample volume and filtrate volume for the routine total metals samples, which were 

needed for the calculation of the total sample concentration. Because ProChem did not have 

extra sample volume to reanalyze the samples, extra sample volume from the low-level total 

metals sample bottles at Battelle were shipped to ProChem for the reanalysis of routine total 

metals. When performing the reanalysis using Battelle’s extra sample volume, ProChem used the 
4-3 

same approach as Battelle (i.e., analyzing the total sample directly), because the laboratory 

determined that the suspended solids present in the sample were at a concentration less than one 

percent; therefore, the phase separation was not required by EPA Method 200.7. The laboratory 

analyzed the total metals directly from the sample bottle. The laboratory had already analyzed 

the dissolved metals concentration; therefore, a solid concentration was calculated using 

Equation 4-2. 

 Table 4-1 presents the results of the biphasic analysis for low-level total metals and 

routine total metals (except routine total mercury, which is discussed below) in the FGD influent 

samples. Only those analytes that were detected at the influent to the FGD wastewater treatment 

system (at levels above the reporting limit) are included in the table. Results are rounded to three 

significant figures. Appendix Table A-1 presents all the analytical results from the influent to the 

FGD wastewater treatment system (SP-1) sample analysis, including J-values. 

 For the biphasic classical analyses, ProChem did not measure the original sample volume 

and filtrate volume, which were needed for the calculation of the total sample concentration, and 

they did not have extra sample volume to reanalyze the classicals. Although additional sample 

volume was available for the reanalysis of mercury, by the time the error was recognized, the 

holding time for the mercury analysis had expired. 

 To determine the total sample results for the classical analytes, EPA calculated the 

sample volume using the sample weight and sample density. EPA was also able to calculate the 

filtrate volume using data that had already been collected by the laboratory. Therefore, the 

classical analytes total concentrations were calculated using Equation 4-1 without making any 

assumptions. For the routine total mercury concentration, EPA had to estimate the sample 

volume to calculate the filtrate volume needed for the calculation. As a best available estimate, 

EPA assumed that the sample volume was 500 mL, based on the sample bottle size, knowing that 

the actual volume of sample collected may have been less than or greater than 500 mL. 

 Table 4-2 presents the results of the biphasic analysis for routine total mercury and Table 

4-3 presents the results of the biphasic analysis for ammonia as nitrogen, chloride, sulfate, 

nitrate/nitrite, TKN, and total phosphorus in the FGD influent samples. Only those analytes that 

were detected at the influent to the FGD wastewater treatment system (at levels above the 

reporting limit) are included in the tables. Results are rounded to three significant figures. 

Appendix Table A-1 presents all the analytical results from the influent to the FGD wastewater 

treatment system (SP-1) sample analysis, including J-values. 

 ProChem performed a filtration blank associated with the biphasic sample separation 

process for the FGD influent (SP-1) sample analysis. For the blank, ProChem poured blank 

water through the filter used for the separation and analyzed the filtered blank water for routine 

mercury (note: routine mercury is the only analytical result from the filtration blank that is 

applicable to the biphasic analysis because all other metals were analyzed without the biphasic 

separation). Mercury was not measured in the filtration blank sample above the reporting limit, 

indicating that there was no contamination from the filtration process. Appendix Table A-2 

presents all the routine mercury analytical result from the filtration blank. 
4-4 

4.2 FGD Wastewater Treatment System

 Table 4-4 presents the analytical results of the classical pollutants at the influent to the 

FGD wastewater treatment system (SP-1), the second-stage clarifier overflow from the FGD 

wastewater treatment system (SP-2), and the effluent from the FGD wastewater treatment system 

(average of SP-3 and SP-5 results). Table 4-5 presents the analytical results of the routine and 

low-level metals for these same sampling points. Only those analytes that were detected in one or 

more samples (at levels above the reporting limit) for the sampling episode are included in the 

table. Results are rounded to three significant digits. If an analyte was measured above the 

method detection limit, but below the report limit, “NQ” is reported followed by the samplespecific report limit in parentheses. If an analyte was not detected in a sample above the method 

detection limit, “ND” is reported followed by the sample-specific report limit in parentheses. 

Note that the results presented in Tables 4-4 and 4-5 are not paired results, meaning that sample 

collection across the treatment system was not timed to reflect the amount of time it takes the 

wastewater to pass through the treatment system (approximately 3.5 days). 

 Appendix Tables A-1, A-3, A-4, and A-5 present all the analytical results from the 

influent to the FGD wastewater treatment system (SP-1), the second-stage clarifier overflow 

from the FGD wastewater treatment system (SP-2), the effluent from the FGD wastewater 

treatment system (SP-3), and the duplicate of the effluent from the FGD wastewater treatment 

system (SP-5) sample analyses, including J-values. Appendix Table B-1 presents the analytical 

results for the metal analytes in a format similar to Table 4-5; however, Table B-1 also include 

results where analytes were measured above the method detection level, but below the reporting 

limit (i.e., J-values). 

4.3 Bottom Ash Pond Treatment System

 Table 4-6 presents the analytical results of the classical pollutants at the effluent from the 

bottom ash treatment system (SP-4). Table 4-7 presents the analytical results of the routine and 

low-level metals at the effluent from the bottom ash treatment system (SP-4). Only those 

analytes that were detected in one or more samples (at levels above the reporting limit) for the 

sampling episode are included in the table. Results are rounded to three significant digits. If an 

analyte was measured above the method detection limit, but below the report limit, “NQ” is 

reported followed by the sample-specific report limit in parentheses. If an analyte was not 

detected in a sample above the method detection limit, “ND” is reported followed by the samplespecific report limit in parentheses. Appendix Table A-6 presents all the analytical results from 

the effluent from the bottom ash treatment system (SP-4) sample analysis, including J-values. 

Appendix Table B-2 presents the analytical results for the metal analytes in a format similar to 

Table 4-7; however, Table B-2 also include results where analytes were measured above the 

method detection level, but below the reporting limit (i.e., J-values). 
ND – Not detected (number in parenthesis is the report limit). 

NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is 

the report limit). The analytical result is presented in Appendix A with a J flag designation. 

R – MS/MSD % Recovery outside method acceptance criteria. 

Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

4-5 

Table 4-1. Biphasic Sample Results for Low-Level Total Metals and Routine Total Metals 

Measured Above the Report Limit, FGD Influent, Homer City 

Analyte 

Dissolved Sample 

Result (ug/L) 

Calculated Solid 

Phase Result (mg/kg) 

Total Sample Result 

(ug/L) 

Low-level Total Metals 

Antimony ND (0.400) 2.67 31.1 

Arsenic 24.2 R 103 1,220 

Cadmium 24.5 2.43 52.8 R 

Chromium ND (16.0) 109 1,270 

Copper 11.3 63.2 747 

Lead ND (1.00) 30.2 351 

Mercury 0.0809 50.8 533 

Nickel 1,450 119 2,840 

Selenium 584 253 3,530 

Thallium 23.2 1.21 37.3 

Zinc 34.7 180 2,130 

Routine Total Metals 

Aluminum ND (50.0) 21,700 289,000 

Antimony NQ (20.0) 5.11 86.4 

Arsenic NQ (10.0) 119 1,590 

Barium 149 R 884 11,900 R 

Beryllium 10.5 1.38 28.8 

Boron 254,000 ND (1,500) 224,000 

Cadmium 26.2 9.31 150 

Calcium 1,990,000 92,500 3,220,000 

Chromium ND (10.0) 105 1,400 

Cobalt 201 12.6 369 

Copper 14.5 59.9 811 

Iron ND (100) 62,000 824,000 

Lead NQ (50.0) 24.7 340 

Magnesium 3,100,000 ND (1,500) 2,760,000 

Manganese 173,000 3,910 225,000 

Molybdenum 30.6 25.9 375 

Nickel 1,350 91.0 2,560 

Selenium 656 251 4,000 

Sodium 1,440,000 ND (3,760) 1,430,000 

Thallium 61.2 Exclude Exclude 

Titanium ND (10.0) 97.7 1,300 

Vanadium ND (20.0) 57.6 766 
ND – Not detected (number in parenthesis is the report limit). 

NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is 

the report limit). The analytical result is presented in Appendix A with a J flag designation. 

R – MS/MSD % Recovery outside method acceptance criteria. 

Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

4-6 

Table 4-1. Biphasic Sample Results for Low-Level Total Metals and Routine Total Metals 

Measured Above the Report Limit, FGD Influent, Homer City 

Analyte 

Dissolved Sample 

Result (ug/L) 

Calculated Solid 

Phase Result (mg/kg) 

Total Sample Result 

(ug/L) 

Yttrium 6.28 43.6 586 

Zinc ND (10.0) 143 1,900 
4-7 

Table 4-2. Biphasic Sample Results for Routine Total Mercury, FGD Influent, Homer 

City

Analyte

Aqueous Phase 

Result (mg/L)

Solid Phase Result 

(mg/kg)

Calculated Total 

Sample Result (mg/L) 

Routine Total Metals 

Mercury ND (10.0) 14.5 243

ND – Not detected (number in parenthesis is the report limit). 

Table 4-3. Biphasic Sample Results for Classical Analytes Measured Above the Report 

Limit, FGD Influent, Homer City

Analyte

Aqueous Phase 

Result (mg/L)

Solid Phase Result 

(mg/kg)

Calculated Total 

Sample Result (mg/L) 

Classical Pollutants 

Ammonia As Nitrogen (NH3-N) 3.62 23.8 4.12

Nitrate/Nitrite (NO3-N + NO2-N) 44.0 467 54.5 

Total Kjeldahl Nitrogen (TKN) 9.52 199 14.2 

Chloride 12,000 4,000 11,800

Sulfate 5,900 46,900 6,920

Total Phosphorus 0.680 79.6 2.64
4-8 

Table 4-4. Classical Pollutants Measured Above the Report Limit for the FGD Wastewater Treatment S

Analyte Method Unit FGD Influent (SP-1) 

FGD Second-stage 

Clarifier Overflow 

Effluent (SP-2) 

Classical Pollutants Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 4.12 3.80 Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 54.5 6.00 Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 14.2 13.1 Chloride 4500-CL-C MG/L 11,800 11,500 Sulfate D516-90 MG/L 6,920 2,920 Total Dissolved Solids (TDS) 2540 C MG/L 23,200 20,500 Total Phosphorus 365.3 MG/L 2.64 0.350 Total Suspended Solids (TSS) 2540 D MG/L 13,300 8.00 

a – The FGD effluent results represent the average of the FGD effluent and the duplicate of the FGD effluent analytical measurements. 

R – MS/MSD % Recovery outside method acceptance criteria. < – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

Note: Results shown are not paired samples. See Section 4.2. 
4-9 

a – The FGD effluent results represent the average of the FGD effluent and the duplicate of the FGD effluent analytical measurements. 

NA – Not analyzed. ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. A “NQ” for the average FGD effluent indicates that the original FGD effluent and/o

FGD effluent is a J-value. The analytical result for the original FGD effluent and/or the duplicate of the FGD effluent is presented in A

designation. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. < – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

Note: Results shown are not paired samples. See Section 4.2. 

Table 4-5. Metals Measured Above the Report Limit for the FGD Wastewater Treatment System, 

FGD Influent (SP-1) 

FGD Second-stage Clarifier 

Overflow Effluent (SP-2) FGD Ef

Analyte Method Unit Total Dissolved Total Dissolved Total 

Routine Metals Aluminum 200.7 UG/L 289,000 ND (50.0) ND (50.0) ND (50.0) ND (50.0) Antimony 200.7 UG/L 86.4 NQ (20.0) 20.1 NQ (20.0) <20.8 Arsenic 200.7 UG/L 1,590 NQ (10.0) NQ (10.0) NQ (10.0) NQ (10.0) Barium 200.7 UG/L 11,900 R 149 R 112 116 71.3 Beryllium 200.7 UG/L 28.8 10.5 7.69 7.90 7.68 Boron 200.7 UG/L 224,000 254,000 191,000 187,000 191,000 Cadmium 200.7 UG/L 150 26.2 NQ (5.00) NQ (5.00) NQ (5.00) Calcium 200.7 UG/L 3,220,000 1,990,000 1,740,000 1,520,000 2,000,000 Chromium 200.7 UG/L 1,400 ND (10.0) ND (10.0) NQ (10.0) ND (10.0) Hexavalent Chromium 

D1687-92 UG/L NA ND (2.00) NA ND (2.00) NA 

Cobalt 200.7 UG/L 369 201 NQ (50.0) NQ (50.0) NQ (50.0) Copper 200.7 UG/L 811 14.5 12.3 12.0 12.5 Iron 200.7 UG/L 824,000 ND (100) NQ (100) NQ (100) <117 Lead 200.7 UG/L 340 NQ (50.0) NQ (50.0) ND (50.0) NQ (50.0) Magnesium 200.7 UG/L 2,760,000 3,100,000 2,640,000 2,630,000 2,610,000 Manganese 200.7 UG/L 225,000 173,000 47,700 47,000 30,100 
4-10 

a – The FGD effluent results represent the average of the FGD effluent and the duplicate of the FGD effluent analytical measurements. 

NA – Not analyzed. ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. A “NQ” for the average FGD effluent indicates that the original FGD effluent and/o

FGD effluent is a J-value. The analytical result for the original FGD effluent and/or the duplicate of the FGD effluent is presented in A

designation. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. < – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

Note: Results shown are not paired samples. See Section 4.2. 

Table 4-5. Metals Measured Above the Report Limit for the FGD Wastewater Treatment System, 

FGD Influent (SP-1) 

FGD Second-stage Clarifier 

Overflow Effluent (SP-2) FGD Ef

Analyte Method Unit Total Dissolved Total Dissolved Total 

Mercury 245.1 UG/L 243 ND (10.0) ND (10.0) ND (10.0) ND (10.0) Molybdenum 200.7 UG/L 375 30.6 36.7 35.9 37.6 Nickel 200.7 UG/L 2,560 R 1,350 56.9 56.9 NQ (50.0) Selenium 200.7 UG/L 4,000 R 656 R 187 179 771 Sodium 200.7 UG/L 1,430,000 1,440,000 1,140,000 1,130,000 1,280,000 Thallium 200.7 UG/L Exclude 61.2 ND (10.0) ND (10.0) ND (10.0) Titanium 200.7 UG/L 1,300 R ND (10.0) ND (10.0) ND (10.0) ND (10.0) Vanadium 200.7 UG/L 766 ND (20.0) ND (20.0) ND (20.0) ND (20.0) Yttrium 200.7 UG/L 586 6.28 NQ (5.00) NQ (5.00) NQ (5.00) Zinc 200.7 UG/L 1,900 ND (10.0) ND (10.0) ND (10.0) ND (10.0) Low-Level Metals Antimony 1638 UG/L 31.1 ND (0.400) ND (0.400) ND (0.400) ND (0.400) Arsenic 1638 UG/L 1,220 24.2 R 20.6 21.8 23.0 Cadmium 1638 UG/L 52.8 R 24.5 NQ (2.00) NQ (2.00) NQ (2.00) Chromium 1638 UG/L 1,270 ND (16.0) NQ (16.0) NQ (16.0) NQ (16.0) Hexavalent Chromium 

1636 UG/L NA NA NA ND (2.50) NA 

Copper 1638 UG/L 747 11.3 10.9 9.22 9.67 
4-11 

a – The FGD effluent results represent the average of the FGD effluent and the duplicate of the FGD effluent analytical measurements. 

NA – Not analyzed. ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. A “NQ” for the average FGD effluent indicates that the original FGD effluent and/o

FGD effluent is a J-value. The analytical result for the original FGD effluent and/or the duplicate of the FGD effluent is presented in A

designation. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. < – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

Note: Results shown are not paired samples. See Section 4.2. 

Table 4-5. Metals Measured Above the Report Limit for the FGD Wastewater Treatment System, 

FGD Influent (SP-1) 

FGD Second-stage Clarifier 

Overflow Effluent (SP-2) FGD Ef

Analyte Method Unit Total Dissolved Total Dissolved Total 

Lead 1638 UG/L 351 ND (1.00) NQ (1.00) NQ (1.00) NQ (1.00) Mercury 1631E UG/L 533 0.0809 0.125 0.0245 0.117 Nickel 1638 UG/L 2,840 1,450 111 116 92.1 Selenium 1638 UG/L 3,530 584 238 241 613 Thallium 1638 UG/L 37.3 23.2 16.8 16.6 16.0 Zinc 1638 UG/L 2,130 34.7 15.0 14.4 15.2 
4-12 

Table 4-6. Classical Pollutants Measured Above the Report Limit for the Bottom Ash 

Pond Effluent, Homer City 

Analyte Method Unit 

Bottom Ash Pond 

Effluent (SP-4) 

Classical Pollutants 

Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 0.340 

Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 37.0 

Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1.36 

Chloride 4500-CL-C MG/L 90.0 

Sulfate D516-90 MG/L 1,290 

Total Dissolved Solids (TDS) 2540 C MG/L 1,250 

Total Phosphorus 365.3 MG/L 1.09 

Total Suspended Solids (TSS) 2540 D MG/L 5.00 
L – Sample result between 5x and 10x blank result. 

NA – Not analyzed. 

ND – Not detected (number in parenthesis is the report limit). 

NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is 

the report limit). The analytical result is presented in Appendix A with a J flag designation.

4-13 

Table 4-7. Metals Measured Above the Report Limit for the Bottom Ash Pond Effluent, 

Homer City 

Bottom Ash Pond Effluent (SP-4) 

Analyte Method Unit Total Dissolved 

Routine Total Metals 

Aluminum 200.7 UG/L 323 231 

Antimony 200.7 UG/L NQ (20.0) NQ (20.0) 

Arsenic 200.7 UG/L NQ (10.0) NQ (10.0) 

Barium 200.7 UG/L 101 106 

Beryllium 200.7 UG/L NQ (5.00) NQ (5.00) 

Boron 200.7 UG/L 396 397 

Cadmium 200.7 UG/L NQ (5.00) NQ (5.00) 

Calcium 200.7 UG/L 186,000 192,000 

Chromium 200.7 UG/L NQ (10.0) NQ (10.0) 

Hexavalent Chromium D1687-92 UG/L NA ND (2.00) 

Cobalt 200.7 UG/L NQ (50.0) NQ (50.0) 

Copper 200.7 UG/L NQ (10.0) NQ (10.0) 

Iron 200.7 UG/L 355 106 

Lead 200.7 UG/L ND (50.0) ND (50.0) 

Magnesium 200.7 UG/L 31,800 32,600 

Manganese 200.7 UG/L 128 129 

Mercury 245.1 UG/L ND (0.200) ND (0.200) 

Molybdenum 200.7 UG/L 19.7 20.2 

Nickel 200.7 UG/L NQ (50.0) NQ (50.0) 

Selenium 200.7 UG/L 6.02 6.10 L 

Sodium 200.7 UG/L 106,000 106,000 

Thallium 200.7 UG/L NQ (10.0) NQ (10.0) 

Titanium 200.7 UG/L NQ (10.0) NQ (10.0) 

Vanadium 200.7 UG/L NQ (20.0) NQ (20.0) 

Yttrium 200.7 UG/L NQ (5.00) ND (5.00) 

Zinc 200.7 UG/L 21.6 35.2 

Low-Level Metals 

Antimony 1638 UG/L 1.09 0.990 

Arsenic 1638 UG/L 6.52 5.00 

Cadmium 1638 UG/L NQ (0.500) NQ (0.500) 

Chromium 1638 UG/L NQ (4.00) NQ (4.00) 

Hexavalent Chromium 1636 UG/L NA 3.01 

Copper 1638 UG/L 2.37 2.08 

Lead 1638 UG/L NQ (0.250) NQ (0.250) 
L – Sample result between 5x and 10x blank result. 

NA – Not analyzed. 

ND – Not detected (number in parenthesis is the report limit). 

NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is 

the report limit). The analytical result is presented in Appendix A with a J flag designation.

4-14 

Table 4-7. Metals Measured Above the Report Limit for the Bottom Ash Pond Effluent, 

Homer City 

Bottom Ash Pond Effluent (SP-4) 

Analyte Method Unit Total Dissolved 

Mercury 1631E UG/L 0.00511 0.00141 

Nickel 1638 UG/L 10.7 10.4 

Selenium 1638 UG/L 5.74 5.16 

Thallium 1638 UG/L 1.32 1.31 

Zinc 1638 UG/L 24.2 15.0 
5-1 

5. DATA QUALITY

 QA/QC procedures applicable to the Homer City sampling episode are outlined in the 

Quality Assurance Project Plan for the Steam Electric Detailed Study (QAPP) [3]. This section 

describes the QC procedures used to assess the precision and accuracy of the analytical data 

presented in Section 4 and Appendices A and B. QC practices used for this sampling episode 

include the analysis of matrix spikes, blanks, duplicate samples, and QC standard checks. 

5.1 Analytical Quality Control

 EPA contracted directly with analytical laboratories for the analysis of samples collected 

during this episode. EPA’s Sample Control Center (SCC) verified that the performances of the 

laboratories selected by EPA was acceptable by conducting QC checks of the analytical data as 

specified by SCC’s Quality Assurance Project Plan dated 15 February 2008. SCC data review 

chemists prepared written data review narratives describing any qualifications of the analytical 

data from this episode. The data review narratives are included in Appendix C. 

5.2 Field Quality Control

 This section discusses the bottle blanks, equipment blanks, field blanks, and field 

duplicate sample results. Section 3.8 of the Sampling Plan discusses field QC specifications. 

Tables presented in this section include results for only certain analytes (e.g., only those detected 

in the respective field QC sample or those detected during the sampling episode). Appendix A 

contains the results for all analytes, both detected and nondetected. 

5.2.1 Bottle Blanks 

 EPA collects bottle blanks to evaluate possible contamination from the sample collection 

bottles. Bottle blanks were collected and analyzed for low-level metals by the supplier of the precleaned bottles, Albion Environmental. 

 Albion Environmental collected the bottle blanks for the low-level metals sample bottles 

(1000 mL LDPE), the low-level hexavalent chromium samples bottles (500 mL LDPE), the 

speciation sample bottles (125 mL amber glass bottles), and the 2-L blank water bottles by filling 

the pre-cleaned bottle to the neck with ASTM Type 1 water, preserving the sample with nitric 

acid to a pH <2, and allowing the sample to sit for at least 24 hours. Albion Environmental then 

analyzed the samples using EPA Method 1638. 

 Albion Environmental collected the bottle blanks for the 4-liter blank water bottles by 

filling the pre-cleaned bottle with ASTM Type 1 water and allowing it to soak for approximately 

24 hours. Albion Environmental then poured a representative aliquot into a pre-cleaned LDPE 

sample bottle, preserved the sample with nitric acid to a pH <2, and allowed the sample to sit for 

at least 24 hours. Albion Environmental then analyzed the samples using EPA Method 1638. 

 Albion Environmental collected the bottle blanks for the low-level mercury sample 

bottles (250 flint glass bottles and 1-L borosilicate glass bottles) by filling the pre-cleaned bottle 

to the neck with ASTM Type 1 water, preserving the sample with bromine monochloride, and 
5-2 

allowing the sample to sit for at least 24 hours. Albion Environmental then analyzed the samples 

using EPA Method 1631E. 

 Albion Environmental collected the bottle blank for the 10-liter composite containers by 

filling the container with approximately two liters of ASTM Type 1 water and allowing it to soak 

for approximately 24 hours. During this period, Albion Environmental shook the container 

periodically and changed its orientation to expose all surfaces of the container to the ASTM 

Type 1 water. Albion Environmental then shook the 10-liter container and poured a 

representative sample into a pre-cleaned sample bottle (a LDPE bottle for low-level metals and a 

glass bottle for low-level mercury). The blank samples were then preserved and analyzed 

according to the analytical methods (i.e., EPA Method 1638 or 1631E), as described above for 

the other bottle blank samples. 

 No metals were detected in the bottle blank, indicating that there was no contamination 

from the sample containers. Appendix Table A-7 presents all of the analytical results from the 

bottle blank and equipment blank analyses for all of the equipment used for the collection of 

low-level samples. 

5.2.2 Equipment Blanks 

 EPA collects equipment blanks to evaluate possible contamination from the equipment 

used for sample collection. EPA did not collect specific equipment blanks for this sampling 

program; however, the field blanks as collected (as described in Section 5.2.3) include the 

sampling equipment. In addition, Albion Environmental collected and analyzed equipment 

blanks for low-level metals for each type of pre-cleaned equipment supplied for the episode. 

 Albion Environmental collected the equipment blanks for the capsule filters and 

fabricated tubing sets by pumping approximately 500 mL of ASTM Type 1 water through the 

pre-cleaned filter or tubing set and discarding the water. Albion Environmental then pumped 

additional water through the pre-cleaned filter or tubing set into a pre-cleaned bottle (a LDPE 

bottle for low-level metals and a glass bottle for low-level mercury). The blank samples were 

then preserved and analyzed according to the analytical methods (EPA Method 1638 or 1631E), 

as described in Section 5.2.1 for the bottle blank samples. For the fabricated tubing sets, Albion 

Environmental collected and analyzed equipment blanks for the individual components of the 

tubing sets, the assembled tubing sets, or both. 

 No metals were detected in the equipment blanks, indicating that there was no 

contamination from the sampling equipment. Appendix Table A-7 presents all of the analytical 

results from the bottle blank and equipment blank analyses for all of the equipment used for the 

collection of low-level samples. 

5.2.3 Field Blanks 

 The sampling team collected field blanks (SP-6, SP-7, SP-8, and SP-9) to evaluate 

possible contamination caused by sampling equipment, sampling equipment decontamination 

procedures, sample collection procedures, or atmospheric contamination. EPA analyzed the field 
5-3 

blank samples for the low-level and routine metals analyses, including both total and dissolved 

metals1

. 

 The low-level total metals field blank samples for the influent to the FGD Wastewater 

Treatment System (SP-6) were collected by pouring ASTM Type 1 water through a precleaned 

funnel attached to the silicone tubing used for sample collection. The sampling team shrouded 

the blank water and funnel with a plastic bag while pouring the blank water into the funnel to 

prevent potential atmospheric deposition. In addition, the sample bottles were placed in a 

“cleanbox” to prevent potential atmospheric deposition. The ASTM Type 1 water flowed 

through the funnel and tubing, and was poured into the sample bottles. EPA collected the field 

blank samples separately from the Homer City representative’s field blank samples. Split 

samples were not collected for the field blank samples because the sample split was performed at 

the tap outlet, not within the sample tubing. 

 The low-level and routine total metals field blank samples for the second-stage clarifier 

overflow in the FGD wastewater treatment system (SP-7), the effluent from the FGD Wastewater 

Treatment System (SP-8), and the effluent from the bottom ash pond (SP-9) were collected by 

pumping ASTM Type 1 water through the tubing used for the sample collection. The container 

holding the ASTM Type 1 water was placed in a large plastic bag and the tubing was placed 

directly into the container. The large plastic bag was closed off as quickly as possible to 

minimize potential atmospheric deposition. The sample bottles were placed in a “cleanbox” and 

the ASTM Type 1 water was pumped through the tubing and “Y” splitter, and poured into the 

sample bottles. EPA collected the field blank samples as “true” split samples with Homer City’s 

representative, using the same procedure discussed in the sample collection description (Section 

3.1). 

 The low-level and routine dissolved metals field blank samples for the influent to the 

FGD Wastewater Treatment System (SP-6), the second-stage clarifier overflow in the FGD 

wastewater treatment system (SP-7), the effluent from the FGD Wastewater Treatment System 

(SP-8), and the effluent from the bottom ash pond (SP-9) were collected by pumping ASTM 

Type 1 water through the tubing used for the dissolved metals sample collection and a capsule 

filter. The container holding the ASTM Type 1 water was placed in a large plastic bag and the 

tubing was placed directly into the container. The large plastic bag was closed off as quickly as 

possible to minimize potential atmospheric deposition. The sample bottles were placed in a 

“cleanbox” and the ASTM Type 1 water was pumped through the tubing, capsule filter, and “Y” 

splitter, and poured into the sample bottles. EPA collected the field blank samples as “true” split 

samples with Homer City’s representative, using the same procedure discussed in the sample 

collection description (Section 3.1). 

 

1 EPA did not collect a low-level dissolved mercury field blank sample in the field because the sample filtration was 

performed at the laboratory to minimize potential mercury contamination. The laboratory performed a filtration 

blank prior to filtering the sample, which is assessed as the field blank for the low-level dissolved mercury sample. 

Mercury was detected at a concentration of 0.000315 ug/L in the filtration blank performed for the first day of 

samples, which includes the influent to the FGD wastewater treatment system, the effluent from the FGD 

wastewater treatment system, and the duplicate of the effluent from the FGD wastewater treatment system; however, 

this concentration is below the report limit of 0.0005 ug/L. Therefore, this sample result is flagged as a J-value. 

Mercury was not detected above the method detection limit (0.000188 ug/L) in the filtration blank performed for the 

second day of samples, which includes the FGD second-stage clarifier overflow effluent and the bottom ash pond 

effluent. 
5-4 

 Table 5-1 presents the field blank analytical results for SP-6 through SP-9. Only those 

analytes that were detected in the field blank samples at levels above the reporting limit are 

included in the table. Results are rounded to three significant digits. Appendix Tables A-8 

through A-11 present all the analytical results for the field blanks from the influent to the FGD 

wastewater treatment system (SP-6), second-stage clarifier overflow in the FGD wastewater 

treatment system (SP-7), effluent from the FGD wastewater treatment system (SP-8), and 

effluent from the bottom ash pond (SP-9) sample analyses, including all qualified results and all 

results that were measured above the method detection limit, but below the reporting limit (i.e., 

J-values). 

5.2.4 Field Duplicates 

 The sampling team collected field duplicate samples (SP-5) to assess the sampling 

measurement precision for the episode. Field duplicate samples are separate samples collected 

from the same location as the original sample. The duplicate is filled immediately after the 

original sample, and is stored and analyzed independently. The relative percent difference (RPD) 

between the two sample results is examined to determine the precision of the data. EPA used the 

following equation to calculate the RPD for the duplicate sample results. 

100

2

S D

S D

RPD (%) ×

⎟

⎠

⎞ ⎜

⎝

⎛ +

− = (5-1) 

where: 

S = concentration of the analyte from original sample analysis; 

D = concentration of the analyte from the duplicate sample analysis; and 

RPD = relative percent difference between the original and duplicate sample 

result. 

 During this sampling episode, duplicate samples (SP-5) for all analytes (except 

HEM/SGT-HEM) were collected from the effluent from the FGD wastewater treatment system 

(SP-3). Table 5-1 presents analytical results and the RPD for SP-3 and SP-5 and includes 

analytical results for only those analytes that were detected in one or more samples for the 

sampling episode. Results are rounded to three significant figures. Appendix Tables A-4 and A-5 

present all the analytical results for the effluent from the FGD wastewater treatment system (SP3) and the duplicate of the effluent from the FGD wastewater treatment system (SP-5) sample 

analyses, including all qualified results and all results that were measured above the method 

detection limit, but below the reporting limit (i.e., J-values). 
5-5 

Table 5-1. Field Blank Results Measured Above the Report Limit, Homer City 

Analyte Sample Point Method Unit 

Concentration 

(ug/L) 

Routine Total Metals 

Calcium FGD Effluent 200.7 UG/L 141 

Calcium Bottom Ash Effluent 200.7 UG/L 86.3 

Magnesium Bottom Ash Effluent 200.7 UG/L 220 

Routine Dissolved Metals 

Barium FGD Effluent 200.7 UG/L 4.70 

Calcium FGD Effluent 200.7 UG/L 193 

Magnesium FGD Effluent 200.7 UG/L 221 

Molybdenum FGD Effluent 200.7 UG/L 55.8 

Selenium FGD Effluent 200.7 UG/L 15.1 

Low-Level Dissolved Metals 

Hexavalent Chromium FGD Second-stage Clarifier 

Overflow 

1636 UG/L 3.17 

Hexavalent Chromium FGD Effluent 1636 UG/L 2.56 

Copper Bottom Ash Effluent 1638 UG/L 0.240 

Hexavalent Chromium Bottom Ash Effluent 1636 UG/L 4.36 
5-6 

< – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

R – MS/MSD % Recovery outside method acceptance criteria.

T – MS/MSD RPD outside method acceptance criteria. NC – Not calculated.ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. 

Table 5-2. Field Duplicate Results, Homer City 

Analyte

Original FGD Effluent 

Concentration (SP-3) 

Duplicate FGD Effluent 

Concentration (SP-5) Average Result 

Relat

Diffe

Classical Pollutants Ammonia As Nitrogen (NH3-N) 0.360 0.230 0.295 Nitrate/Nitrite (NO3-N + NO2-N) 37.0 36.0 R 36.5 Total Kjeldahl Nitrogen (TKN) 2.96 3.11 3.04 Chloride 12,000 11,500 11,800 Sulfate 2,520 3,050 2,790 Total Dissolved Solids (TDS) 23,800 21,300 22,600 Total Phosphorus 0.720 0.320 0.520 Total Suspended Solids (TSS) ND (5.00) 6.00 < 5.50 Routine Total Metals Aluminum ND (50.0) ND (50.0) ND (50.0) Antimony NQ (20.0) 21.5 < 20.8 Arsenic NQ (10.0) NQ (10.0) ND (10.0) Barium 71.1 R 71.4 71.3 Beryllium 7.61 7.74 7.68 Boron 188,000 193,000 191,000 Cadmium NQ (5.00) NQ (5.00) ND (5.00) Calcium 1,920,000 2,070,000 2,000,000 Chromium ND (10.0) ND (10.0) ND (10.0) Cobalt NQ (50.0) NQ (50.0) ND (50.0) Copper 13.0 12.0 12.5 Iron 134 NQ (100) < 117 Lead NQ (50.0) NQ (50.0) ND (50.0) 
5-7 

< – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

R – MS/MSD % Recovery outside method acceptance criteria.

T – MS/MSD RPD outside method acceptance criteria. NC – Not calculated.ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. 

Table 5-2. Field Duplicate Results, Homer City 

Analyte

Original FGD Effluent 

Concentration (SP-3) 

Duplicate FGD Effluent 

Concentration (SP-5) Average Result 

Relat

Diffe

Magnesium 2,560,000 2,650,000 2,610,000 Manganese 29,800 30,300 30,100 Mercury ND (10.0) ND (10.0) ND (10.0) Molybdenum 37.9 37.2 37.6 Nickel NQ (50.0) NQ (50.0) ND (50.0) Selenium 773 768 771 Sodium 1,280,000 1,270,000 1,280,000 Thallium ND (10.0) ND (10.0) ND (10.0) Titanium ND (10.0) ND (10.0) ND (10.0) Vanadium ND (20.0) ND (20.0) ND (20.0) Yttrium NQ (5.00) NQ (5.00) ND (5.00) Zinc ND (10.0) ND (10.0) ND (10.0) Routine Dissolved Metals Aluminum ND (50.0) ND (50.0) ND (50.0) Antimony NQ (20.0) NQ (20.0) ND (20.0) Arsenic NQ (10.0) NQ (10.0) ND (10.0) Barium 71.9 R,T 69.2 70.6 Beryllium 7.74 7.68 7.71 Boron 182,000 185,000 184,000 Cadmium NQ (5.00) NQ (5.00) ND (5.00) Calcium 1,970,000 1,880,000 1,930,000 Chromium ND (10.0) ND (10.0) ND (10.0) Hexavalent Chromium ND (2.00) ND (2.00) ND (2.00) 
5-8 

< – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

R – MS/MSD % Recovery outside method acceptance criteria.

T – MS/MSD RPD outside method acceptance criteria. NC – Not calculated.ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. 

Table 5-2. Field Duplicate Results, Homer City 

Analyte

Original FGD Effluent 

Concentration (SP-3) 

Duplicate FGD Effluent 

Concentration (SP-5) Average Result 

Relat

Diffe

Cobalt NQ (50.0) NQ (50.0) ND (50.0) Copper 11.6 11.9 11.8 Iron 134 R 197 166 Lead NQ (50.0) NQ (50.0) ND (50.0) Magnesium 2,520,000 2,500,000 2,510,000 Manganese 29,200 29,000 29,100 Mercury ND (10.0) ND (10.0) ND (10.0) Molybdenum 36.3 35.2 35.8 Nickel NQ (50.0) NQ (50.0) ND (50.0) Selenium 766 R 715 741 Sodium 1,250,000 1,210,000 1,230,000 Thallium ND (10.0) ND (10.0) ND (10.0) Titanium ND (10.0) ND (10.0) ND (10.0) Vanadium ND (20.0) NQ (20.0) ND (20.0) Yttrium NQ (5.00) NQ (5.00) ND (5.00) Zinc NQ (10.0) ND (10.0) ND (10.0) Low-Level Total Metals Antimony ND (0.400) ND (0.400) ND (0.400) Arsenic 23.5 22.4 23.0 Cadmium NQ (2.00) NQ (2.00) ND (2.00) Chromium NQ (16.0) NQ (16.0) ND (16.0) Copper 9.44 9.90 9.67 Lead NQ (1.00) NQ (1.00) ND (1.00) 
5-9 

< – Average result includes at least one non-detect value. (Calculation uses detection limit for non-detected results). 

R – MS/MSD % Recovery outside method acceptance criteria.

T – MS/MSD RPD outside method acceptance criteria. NC – Not calculated.ND – Not detected (number in parenthesis is the report limit). NQ – Analyte was measured above the method detection limit, but below the report limit (number in parenthesis is the report limit). Thpresented in Appendix A with a J flag designation. 

Table 5-2. Field Duplicate Results, Homer City 

Analyte

Original FGD Effluent 

Concentration (SP-3) 

Duplicate FGD Effluent 

Concentration (SP-5) Average Result 

Relat

Diffe

Mercury 0.117 0.117 0.117 Nickel 92.0 92.2 92.1 Selenium 621 605 613 Thallium 15.9 16.0 16.0 Zinc 15.2 15.2 15.2 Low-Level Dissolved Metals Antimony ND (0.400) ND (0.400) ND (0.400) Arsenic 22.5 22.4 22.5 Cadmium NQ (2.00) NQ (2.00) ND (2.00) Chromium NQ (16.0) NQ (16.0) ND (16.0) Hexavalent Chromium ND (2.50) ND (2.50) ND (2.50) Copper 9.26 9.52 9.39 Lead ND (1.00) NQ (1.00) ND (1.00) Mercury 0.0556 0.0528 0.0542 Nickel 93.7 93.3 93.5 Selenium 606 634 620 Thallium 15.8 15.8 15.8 Zinc 15.2 16.2 15.7 
6-1

6. REFERENCES

1. Eastern Research Group, Inc., 2007. Final Engineering Site Visit Report for EME Homer 

City Generation L.P.’s, Homer City Power Plant. August 9. DCN 04718. EPA-HQ-OW2006-0071-0695. 

2. Eastern Research Group, Inc., 2007. Sampling Plan, EME Homer City Generation L.P.’s 

Homer City Power Plant. August 17. DCN 04860A1. EPA-HQ-OW-2006-0071-0649.1. 

3. Eastern Research Group, Inc., 2007. Quality Assurance Project Plan for the Steam 

Electric Detailed Study. September 25. DCN 05079. EPA-HQ-OW-2006-0071-0724. 

4. U.S. EPA. 2001. Method 200.7: Trace Elements in Water, Solids, and Biosolids, by 

Inductively Coupled Plasma-Atomic Emission Spectrometry. Revision 5.0. EPA-821-R01-010. January. 
Appendix A 

ANALYTICAL RESULTS 
A-1 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Classical Pollutants – Total Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L NA NP NP Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L NA NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L NA NP NP Biochemical Oxygen Demand (BOD) 5210B MG/L 120 NP NP Chloride 4500-CL-C MG/L NA NP NP Hexane Extractable Material (HEM) 1664A MG/L 1 NP NP Sulfate D516-90 MG/L NA NP NP Total Dissolved Solids (TDS) 2540 C MG/L 1 NP NP Total Phosphorus 365.3 MG/L NA NP NP Total Suspended Solids (TSS) 2540 D MG/L 1 NP NP Classical Pollutants – Solid (wet weight) Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/KG 1 NP NP Nitrate/Nitrite (NO3-N + NO2-N) 1685 MG/KG 1 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/KG 1 NP NP Chloride 4500-CL-C MG/KG 1 NP NP Sulfate D516-90 MG/KG 5,000 NP NP Total Phosphorus 365.3 MG/KG 1 NP NP Classical Pollutants – Filtered Aqueous Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 1 NP NP 
A-2 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 10 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1 NP NP Chloride 4500-CL-C MG/L 50 NP NP Sulfate D516-90 MG/L 200 NP NP Total Phosphorus 365.3 MG/L 1 NP NP Routine Metals – Total Aluminum 200.7 UG/L 20 212 1,000 Antimony 200.7 UG/L 2 1.40 40.0 Arsenic 200.7 UG/L 2 1.00 20.0 Barium 200.7 UG/L 20 2.00 40.0 Beryllium 200.7 UG/L 2 1.00 10.0 Boron 200.7 UG/L 200 540 20,000 Cadmium 200.7 UG/L 2 0.200 10.0 Calcium 200.7 UG/L 20 102 1,000 Chromium 200.7 UG/L 2 0.400 20.0 Cobalt 200.7 UG/L 2 1.20 100 Copper 200.7 UG/L 2 0.400 20.0 Iron 200.7 UG/L 20 108 2,000 Lead 200.7 UG/L 2 1.40 100 Magnesium 200.7 UG/L 20 178 4,000 
A-3 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Manganese 200.7 UG/L 200 40.0 3,000 Mercury 245.1 UG/L NA NC 22.0 Molybdenum 200.7 UG/L 2 0.400 20.0 Nickel 200.7 UG/L 2 2.20 100 Selenium 200.7 UG/L 2 1.20 10.0 Silver 200.7 UG/L 2 0.800 40.0 Sodium 200.7 UG/L 20 810 10,000 Thallium 200.7 UG/L 2 1.00 20.0 Tin 200.7 UG/L 2 0.800 60.0 Titanium 200.7 UG/L 2 0.400 20.0 Vanadium 200.7 UG/L 2 1.20 40.0 Yttrium 200.7 UG/L 2 0.400 10.0 Zinc 200.7 UG/L 2 0.400 20.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 
A-4 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 
A-5 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Filtered Aqueous Mercury 245.1 UG/L 50 2.50 10.0 Routine Metals – Solid (wet weight) Mercury 245.5 MG/KG 50 0.300 1.25 Routine Metals – Solid (dry weight) Aluminum 200.7 MG/KG NA 15.9 75.2 Antimony 200.7 MG/KG NA 0.105 3.01 Arsenic 200.7 MG/KG NA 0.0752 1.50 Barium 200.7 MG/KG NA 0.150 3.01 Beryllium 200.7 MG/KG NA 0.0752 0.752 Boron 200.7 MG/KG NA 40.6 1,500 Cadmium 200.7 MG/KG NA 0.0150 0.752 Calcium 200.7 MG/KG NA 38.3 376 Chromium 200.7 MG/KG NA 0.0301 1.50 Cobalt 200.7 MG/KG NA 0.0902 7.52 Copper 200.7 MG/KG NA 0.0301 1.50 Iron 200.7 MG/KG NA 8.12 150 Lead 200.7 MG/KG NA 0.105 7.52 
A-6 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Magnesium 200.7 MG/KG NA 66.9 1,500 Manganese 200.7 MG/KG NA 3.01 226 Molybdenum 200.7 MG/KG NA 0.0301 1.50 Nickel 200.7 MG/KG NA 0.165 7.52 Selenium 200.7 MG/KG NA 0.0902 0.752 Silver 200.7 MG/KG NA 0.0602 3.01 Sodium 200.7 MG/KG NA 305 3,760 Thallium 200.7 MG/KG NA 0.0752 1.50 Tin 200.7 MG/KG NA 0.0602 4.51 Titanium 200.7 MG/KG NA 0.0301 1.50 Vanadium 200.7 MG/KG NA 0.0902 3.01 Yttrium 200.7 MG/KG NA 0.0301 0.752 Zinc 200.7 MG/KG NA 0.0301 1.50 Low-Level Metals – Total Antimony 1638 UG/L 200 1.40 4.00 Arsenic 1638 UG/L 200 3.04 30.0 Cadmium 1638 UG/L 200 0.200 20.0 Chromium 1638 UG/L 200 16.6 160 Copper 1638 UG/L 200 0.800 40.0 Lead 1638 UG/L 200 0.200 10.0 
A-7 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Mercury 1631E UG/L 1,000 0.188 0.500 Nickel 1638 UG/L 200 2.60 200 Selenium 1638 UG/L 200 3.20 200 Silver 1638 UG/L 200 0.400 20.0 Thallium 1638 UG/L 200 0.0800 4.00 Zinc 1638 UG/L 200 41.8 100 Low-Level Metals - Dissolved Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 100 0.0188 0.0500 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 
A-8 

NA – Not applicable. Calculated value. NC – A sample-specific MDL was not calculated for the analyte. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. 

Table A-1. FGD Influent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor 

Sample-Specific 

MDL 

SampleSpecific RL 

Low-Level Metals – Solid (dry weight) Antimony 1638 MG/KG NA 0.120 0.344 Arsenic 1638 MG/KG NA 0.261 2.58 Cadmium 1638 MG/KG NA 0.0189 1.72 Chromium 1638 MG/KG NA 1.43 13.8 Copper 1638 MG/KG NA 0.0688 3.44 Lead 1638 MG/KG NA 0.0172 0.859 Mercury 1631E MG/KG NA 0.0179 0.0477 Nickel 1638 MG/KG NA 0.224 17.2 Selenium 1638 MG/KG NA 0.275 17.2 Silver 1638 MG/KG NA 0.0344 1.72 Thallium 1638 MG/KG NA 0.00690 0.344 Zinc 1638 MG/KG NA 3.59 8.59 
A-9 

Table A-2. ProChem Biphasic Filtration Blank Analytical Results, Homer City 

Analyte Method Unit 

Dilution 

Factor 

Sample-Specific 

MDL 

Sample-Specific 

RL Concentration 

Mercury 245.1 UG/L 1 0.0500 0.200 ND (0.200) U 

ND – Not detected (number in parenthesis is the report limit). 

U – Result below the MDL. Number shown in parentheses is the reporting limit). 
A-10 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-3. FGD Second-Stage Clarifier Overflow Effluent Analytical Data, Homer Cit

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Classical Pollutants Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 1 NP NP Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 5 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1 NP NP Biochemical Oxygen Demand (BOD) 5210B MG/L 60 NP NP Chloride 4500-CL-C MG/L 50 NP NP Hexane Extractable Material (HEM) 1664A MG/L 1 NP NP Sulfate D516-90 MG/L 100 NP NP Total Dissolved Solids (TDS) 2540 C MG/L 1 NP NP Total Phosphorus 365.3 MG/L 1 NP NP Total Suspended Solids (TSS) 2540 D MG/L 1 NP NP Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 
A-11 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-3. FGD Second-Stage Clarifier Overflow Effluent Analytical Data, Homer Cit

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 
A-12 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-3. FGD Second-Stage Clarifier Overflow Effluent Analytical Data, Homer Cit

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Low-Level Metals – Total Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 
A-13 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-3. FGD Second-Stage Clarifier Overflow Effluent Analytical Data, Homer Cit

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Chromium 1638 UG/L 20 1.66 16.0 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 5 0.000940 0.00250 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 Low-Level Metals - Dissolved Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 5 0.000940 0.00250 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 
A-14 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-4. FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Classical Pollutants Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 1 NP NP Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 10 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1 NP NP Biochemical Oxygen Demand (BOD) 5210B MG/L 120 NP NP Chloride 4500-CL-C MG/L 50 NP NP Hexane Extractable Material (HEM) 1664A MG/L 1 NP NP Sulfate D516-90 MG/L 100 NP NP Total Dissolved Solids (TDS) 2540 C MG/L 1 NP NP Total Phosphorus 365.3 MG/L 1 NP NP Total Suspended Solids (TSS) 2540 D MG/L 1 NP NP Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 
A-15 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-4. FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 
A-16 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-4. FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 
A-17 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-4. FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Low-Level Metals – Total Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 100 0.0188 0.0500 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 Low-Level Metals - Dissolved Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 100 0.0188 0.0500 Nickel 1638 UG/L 20 0.260 20.0 
A-18 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-4. FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 
A-19 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-5. Duplicate of FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Classical Pollutants Ammonia As Nitrogen (NH3-N)) 4500-NH3F MG/L 1 NP NP Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 25 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1 NP NP Biochemical Oxygen Demand (BOD) 5210B MG/L 120 NP NP Chloride 4500-CL-C MG/L 50 NP NP Sulfate D516-90 MG/L 100 NP NP Total Dissolved Solids (TDS) 2540 C MG/L 1 NP NP Total Phosphorus 365.3 MG/L 1 NP NP Total Suspended Solids (TSS) 2540 D MG/L 1 NP NP Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 
A-20 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-5. Duplicate of FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 100 270 10,000 Cadmium 200.7 UG/L 1 0.100 5.00 
A-21 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-5. Duplicate of FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Calcium 200.7 UG/L 100 510 5,000 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 100 890 20,000 Manganese 200.7 UG/L 100 20.0 1,500 Mercury 245.1 UG/L 50 2.50 10.0 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 100 4,050 50,000 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Low-Level Metals – Total Antimony 1638 UG/L 20 0.140 0.400 
A-22 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-5. Duplicate of FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 100 0.0188 0.0500 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 Low-Level Metals - Dissolved Antimony 1638 UG/L 20 0.140 0.400 Arsenic 1638 UG/L 20 0.304 3.00 Cadmium 1638 UG/L 20 0.0200 2.00 Chromium 1638 UG/L 20 1.66 16.0 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 20 0.0800 4.00 Lead 1638 UG/L 20 0.0200 1.00 Mercury 1631E UG/L 100 0.0188 0.0500 Nickel 1638 UG/L 20 0.260 20.0 Selenium 1638 UG/L 20 0.320 20.0 Silver 1638 UG/L 20 0.0400 2.00 
A-23 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. R – MS/MSD % Recovery outside method acceptance criteria. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-5. Duplicate of FGD Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific R

Thallium 1638 UG/L 20 0.00800 0.400 Zinc 1638 UG/L 20 4.18 10.0 
A-24 

J – Result measured above the MDL, but less than the reporting limit. L – Sample result between 5x and 10x blank result. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-6. Bottom Ash Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Classical Pollutants Ammonia As Nitrogen (NH3-N) 4500-NH3F MG/L 1 NP NP Nitrate/Nitrite (NO3-N + NO2-N) 353.2 MG/L 10 NP NP Total Kjeldahl Nitrogen (TKN) 4500-N,C MG/L 1 NP NP Biochemical Oxygen Demand (BOD) 5210B MG/L 1 NP NP Chloride 4500-CL-C MG/L 1 NP NP Hexane Extractable Material (HEM) 1664A MG/L 1 NP NP Sulfate D516-90 MG/L 100 NP NP Total Dissolved Solids (TDS) 2540 C MG/L 1 NP NP Total Phosphorus 365.3 MG/L 1 NP NP Total Suspended Solids (TSS) 2540 D MG/L 1 NP NP Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 10 51.0 500 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 
A-25 

J – Result measured above the MDL, but less than the reporting limit. L – Sample result between 5x and 10x blank result. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-6. Bottom Ash Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 
A-26 

J – Result measured above the MDL, but less than the reporting limit. L – Sample result between 5x and 10x blank result. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-6. Bottom Ash Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 10 51.0 500 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 
A-27 

J – Result measured above the MDL, but less than the reporting limit. L – Sample result between 5x and 10x blank result. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-6. Bottom Ash Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Low-Level Metals – Total Antimony 1638 UG/L 5 0.0350 0.100 Arsenic 1638 UG/L 5 0.0760 0.750 Cadmium 1638 UG/L 5 0.00500 0.500 Chromium 1638 UG/L 5 0.415 4.00 Copper 1638 UG/L 5 0.0200 1.00 Lead 1638 UG/L 5 0.00500 0.250 Mercury 1631E UG/L 5 0.000940 0.00250 Nickel 1638 UG/L 5 0.0650 5.00 Selenium 1638 UG/L 5 0.0800 5.00 Silver 1638 UG/L 5 0.0100 0.500 Thallium 1638 UG/L 5 0.00200 0.100 Zinc 1638 UG/L 5 1.05 2.50 Low-Level Metals - Dissolved Antimony 1638 UG/L 5 0.0350 0.100 Arsenic 1638 UG/L 5 0.0760 0.750 Cadmium 1638 UG/L 5 0.00500 0.500 Chromium 1638 UG/L 5 0.415 4.00 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 5 0.0200 1.00 Lead 1638 UG/L 5 0.00500 0.250 Mercury 1631E UG/L 1 0.000188 0.000500 Nickel 1638 UG/L 5 0.0650 5.00 
A-28 

J – Result measured above the MDL, but less than the reporting limit. L – Sample result between 5x and 10x blank result. ND – Not detected (number in parenthesis is the report limit). NP – Not provided. The sample-specific MDL and sample-specific RL are only provided for the metal analytes because EPA is presen

metals that are quantified below the report limit. For this analyte, only values above the report limit are presented. If the analyte was n

report limit, the report limit is presented in parentheses in the concentration column. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-6. Bottom Ash Effluent Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Selenium 1638 UG/L 5 0.0800 5.00 Silver 1638 UG/L 5 0.0100 0.500 Thallium 1638 UG/L 5 0.00200 0.100 Zinc 1638 UG/L 5 1.05 2.50 
ND – Not detected (number in parenthesis is the report limit). 

A-29 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

LDPE 1000 ml Plastic Bottles – Bottle Blank (for low-level metals samples)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

LDPE 500 ml Plastic Bottles – Bottle Blank (for low-level hexavalent chromium samples)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 
ND – Not detected (number in parenthesis is the report limit). 

A-30 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Flint 125 ml Amber Glass Bottles – Bottle Blank (for speciation samples)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

Flint 250 ml Glass Bottles – Bottle Blank (for low-level mercury samples)

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Capsule Filter – Equipment Blank (for dissolved low-level metals sample collection)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Dissolved UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 
ND – Not detected (number in parenthesis is the report limit). 

A-31 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

LDPE 4000 ml Plastic Bottles – Bottle Blank (for low-level metals field blank water)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

LDPE 2000 ml Plastic Bottles – Bottle Blank (for low-level metals field blank water)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 
ND – Not detected (number in parenthesis is the report limit). 

A-32 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Borosilicate 1000 ml Glass Bottles – Bottle Blank (for low-level mercury field blank water)

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

LDPE 10 L Composite Bottles – Bottle Blank (sample composite bottle for dissolved/filtration pump-off)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

Pump-Off Tubing Set – Equipment Blank (Teflon® and silicone tubing for dissolved sample collection for 

low-level metals)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 
ND – Not detected (number in parenthesis is the report limit). 

A-33 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

C-Flex Tubing Set – Equipment Blank (#73 silicone tubing attached to #24 silicone tubing for sample 

collection for low-level mercury and metals from FGD influent sample tap)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

Tubing Set – Equipment Blank (25 feet of Teflon® tubing, 5 feet #24 silicone tubing, Y-splitter, two pieces 

of 5 feet #24 silicone tubing for sample collection for low-level mercury and metals from FGD primary 

clarifier effluent, effluent from FGD wastewater treatment system, and bottom ash pond effluent)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 
ND – Not detected (number in parenthesis is the report limit). 

A-34 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

Funnel Assembly Set – Equipment Blank (Plastic funnel attached to #73 silicone tubing for field blank 

sample collection for low-level total metals at the FGD influent)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 

C-Flex Tubing Set – Equipment Blank (10 feet #73 silicone tubing, Y-splitter, two pieces of 5 feet #24 

silicone tubing for alternative sample collection approach for low-level mercury and metals from FGD 

influent sample tap)

Aluminum EPA 1638 Dissolved UG/L ND (2.0) 

Antimony EPA 1638 Dissolved UG/L ND (0.50) 

Arsenic EPA 1638 Dissolved UG/L ND (0.50) 

Barium EPA 1638 Dissolved UG/L ND (0.10) 

Beryllium EPA 1638 Dissolved UG/L ND (0.10) 

Cadmium EPA 1638 Dissolved UG/L ND (0.10) 

Chromium EPA 1638 Dissolved UG/L ND (1.0) 

Cobalt EPA 1638 Dissolved UG/L ND (0.10) 

Copper EPA 1638 Dissolved UG/L ND (0.30) 

Lead EPA 1638 Dissolved UG/L ND (0.050) 

Manganese EPA 1638 Dissolved UG/L ND (0.50) 

Mercury EPA 1631E Total Recoverable UG/L ND (0.00020) 
ND – Not detected (number in parenthesis is the report limit). 

A-35 

Table A-7. Bottle Blank and Equipment Blank Analytical Data, Homer City 

Analyte Method Process Units Concentration 

Molybdenum EPA 1638 Dissolved UG/L ND (0.50) 

Nickel EPA 1638 Dissolved UG/L ND (0.50) 

Selenium EPA 1638 Dissolved UG/L ND (2.0) 

Silver EPA 1638 Dissolved UG/L ND (0.10) 

Thallium EPA 1638 Dissolved UG/L ND (0.050) 

Vanadium EPA 1638 Dissolved UG/L ND (1.0) 

Zinc EPA 1638 Dissolved UG/L ND (0.50) 
A-36 

ND – Not detected (number in parenthesis is the report limit). J – Result measured above the MDL, but less than the reporting limit. U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-8. FGD Influent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Low-Level Metals – Total Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 Mercury 1631E UG/L 1 0.000188 0.000500 Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 Low-Level Metals - Dissolved Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 
A-37 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-9. FGD Second-Stage Clarifier Overflow Field Blank Analytical Data, Homer C

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 
A-38 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-9. FGD Second-Stage Clarifier Overflow Field Blank Analytical Data, Homer C

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 
A-39 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-9. FGD Second-Stage Clarifier Overflow Field Blank Analytical Data, Homer C

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Low-Level Metals – Total Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 Mercury 1631E UG/L 1 0.000188 0.000500 Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 Low-Level Metals - Dissolved Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 
A-40 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-9. FGD Second-Stage Clarifier Overflow Field Blank Analytical Data, Homer C

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL 

Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 
A-41 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-10. FGD Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 
A-42 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-10. FGD Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 
A-43 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-10. FGD Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Low-Level Metals – Total Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 Mercury 1631E UG/L 1 0.000188 0.000500 Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 Low-Level Metals - Dissolved Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 
A-44 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-10. FGD Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific RL Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 
A-45 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-11. Bottom Ash Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific 

Routine Metals – Total Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 
A-46 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-11. Bottom Ash Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific 

Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Routine Metals – Dissolved Aluminum 200.7 UG/L 1 10.6 50.0 Antimony 200.7 UG/L 1 0.700 20.0 Arsenic 200.7 UG/L 1 0.500 10.0 Barium 200.7 UG/L 1 0.100 2.00 Beryllium 200.7 UG/L 1 0.500 5.00 Boron 200.7 UG/L 1 2.70 100 Cadmium 200.7 UG/L 1 0.100 5.00 Calcium 200.7 UG/L 1 5.10 50.0 Chromium 200.7 UG/L 1 0.200 10.0 Hexavalent Chromium D1687-92 UG/L 1 1.00 2.00 Cobalt 200.7 UG/L 1 0.600 50.0 Copper 200.7 UG/L 1 0.200 10.0 Iron 200.7 UG/L 1 5.40 100 Lead 200.7 UG/L 1 0.700 50.0 Magnesium 200.7 UG/L 1 8.90 200 Manganese 200.7 UG/L 1 0.200 15.0 Mercury 245.1 UG/L 1 0.0500 0.200 Molybdenum 200.7 UG/L 1 0.200 10.0 Nickel 200.7 UG/L 1 1.10 50.0 Selenium 200.7 UG/L 1 0.600 5.00 Silver 200.7 UG/L 1 0.400 20.0 Sodium 200.7 UG/L 1 40.5 500 Thallium 200.7 UG/L 1 0.500 10.0 
A-47 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-11. Bottom Ash Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific 

Tin 200.7 UG/L 1 0.400 30.0 Titanium 200.7 UG/L 1 0.200 10.0 Vanadium 200.7 UG/L 1 0.600 20.0 Yttrium 200.7 UG/L 1 0.200 5.00 Zinc 200.7 UG/L 1 0.200 10.0 Low-Level Metals – Total Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 Mercury 1631E UG/L 1 0.000188 0.000500 Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 Low-Level Metals - Dissolved Antimony 1638 UG/L 1 0.00700 0.0200 Arsenic 1638 UG/L 1 0.0152 0.150 Cadmium 1638 UG/L 1 0.00100 0.100 Chromium 1638 UG/L 1 0.0830 0.800 Hexavalent Chromium 1636 UG/L 5 1.75 2.50 Copper 1638 UG/L 1 0.00400 0.200 Lead 1638 UG/L 1 0.00100 0.0500 
A-48 

J – Result measured above the MDL, but less than the reporting limit. ND – Not detected (number in parenthesis is the report limit). U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

Table A-11. Bottom Ash Effluent Field Blank Analytical Data, Homer City 

Analyte Method Unit Dilution Factor Sample-Specific MDL Sample-Specific 

Nickel 1638 UG/L 1 0.0130 1.00 Selenium 1638 UG/L 1 0.0160 1.00 Silver 1638 UG/L 1 0.00200 0.100 Thallium 1638 UG/L 1 0.000400 0.0200 Zinc 1638 UG/L 1 0.209 0.500 
Appendix B 

ANALYTICAL DATA FOR METALS, FGD WASTEWATER AND BOTTOM ASH POND
B-1 

J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. Number shown in parentheses is the reporting limit). NA – Not analyzed. ND – Not detected (number in parenthesis is the report limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. Note: Results shown are not paired samples. See Section 4.2. 

Table B-1. Analytical Results for Metals in the FGD Wastewater Treatment System, Home

FGD Influent (SP-1) 

Second-Stage Clarifier 

Overflow Effluent (SP-2) Original FGD Effluent (SP-3) 

D

Analyte Method Unit Total Dissolved Total Dissolved Total Dissolved 

Routine Metals Aluminum 200.7 UG/L 289,000 ND (50.0) U ND (50.0) U ND (50.0) U ND (50.0) U ND (50.0) U ND (Antimony 200.7 UG/L 86.4 18.4 J 20.1 14.0 J 13.6 J 14.0 J 21Arsenic 200.7 UG/L 1,590 7.51 J 3.81 J 3.05 J 3.60 J 3.56 J 3.Barium 200.7 UG/L 11,900 R 149 R 112 116 71.1 R 71.9 R,T 71Beryllium 200.7 UG/L 28.8 10.5 7.69 7.90 7.61 7.74 7.Boron 200.7 UG/L 224,000 254,000 191,000 187,000 188,000 182,000 193Cadmium 200.7 UG/L 150 26.2 3.93 J 3.58 J 3.24 J 3.30 J 3.Calcium 200.7 UG/L 3,220,000 1,990,000 1,740,000 1,520,000 1,920,000 1,970,000 2,070Chromium 200.7 UG/L 1,400 ND (10.0) U ND (10.0) U 2.46 J ND (10.0) U ND (10.0) U ND (Hexavalent Chromium 

D1687-92 UG/L NA ND (2.00) U NA ND (2.00) U NA ND (2.00) U N

Cobalt 200.7 UG/L 369 201 10.8 J 10.7 J 6.36 J 6.27 J 6.Copper 200.7 UG/L 811 14.5 12.3 12.0 13.0 11.6 12Iron 200.7 UG/L 824,000 ND (100) U 85.9 J 85.4 J 134 134 R 86Lead 200.7 UG/L 340 11.5 J 3.17 J ND (50.0) U 0.987 J 2.58 J 1.Magnesium 200.7 UG/L 2,760,000 3,100,000 2,640,000 2,630,000 2,560,000 2,520,000 2,650Manganese 200.7 UG/L 225,000 173,000 47,700 47,000 29,800 29,200 30,Mercury 245.1 UG/L 243 ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U ND (Molybdenum 200.7 UG/L 375 30.6 36.7 35.9 37.9 36.3 37Nickel 200.7 UG/L 2,560 R 1,350 56.9 56.9 34.0 J 31.7 J 33Selenium 200.7 UG/L 4,000 R 656 R 187 179 773 766 R 76Silver 200.7 UG/L 34.6 J 7.93 J ND (20.0) U ND (20.0) U ND (20.0) U ND (20.0) U ND (
B-2 

J – Result measured above the MDL, but less than the reporting limit. R – MS/MSD % Recovery outside method acceptance criteria. T – MS/MSD RPD outside method acceptance criteria. U – Result below the MDL. Number shown in parentheses is the reporting limit). NA – Not analyzed. ND – Not detected (number in parenthesis is the report limit). Exclude – Results were excluded because the MS/MSD samples had a zero percent recovery for total thallium. Note: Results shown are not paired samples. See Section 4.2. 

Table B-1. Analytical Results for Metals in the FGD Wastewater Treatment System, Home

FGD Influent (SP-1) 

Second-Stage Clarifier 

Overflow Effluent (SP-2) Original FGD Effluent (SP-3) 

D

Analyte Method Unit Total Dissolved Total Dissolved Total Dissolved 

Sodium 200.7 UG/L 1,430,000 1,440,000 1,140,000 1,130,000 1,280,000 1,250,000 1,270Thallium 200.7 UG/L Exclude 61.2 ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U ND (Tin 200.7 UG/L 38.1 J ND (30.0) U 0.938 J 1.88 J 3.41 J 4.41 J 0.5Titanium 200.7 UG/L 1,300 R ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U ND (Vanadium 200.7 UG/L 766 ND (20.0) U ND (20.0) U ND (20.0) U ND (20.0) U ND (20.0) U ND (Yttrium 200.7 UG/L 586 6.28 1.52 J 1.62 J 1.46 J 1.53 J 1.Zinc 200.7 UG/L 1,900 ND (10.0) U ND (10.0) U ND (10.0) U ND (10.0) U 9.62 J ND (Low-Level Metals Antimony 1638 UG/L 31.1 ND (0.400) U ND (0.400) U ND 

(0.400) 

U ND (0.400) U ND 

(0.400) 

U ND (0

Arsenic 1638 UG/L 1,220 24.2 R 20.6 21.8 23.5 22.5 22Cadmium 1638 UG/L 52.8 R 24.5 1.74 J 1.69 J 1.77 J 1.61 J 1.Chromium 1638 UG/L 1,270 ND (16.0) U 8.76 J 9.27 J 10.4 J 10.2 J 11Hexavalent Chromium 

1636 UG/L NA NA NA ND (2.50) U NA ND (2.50) U N

Copper 1638 UG/L 747 11.3 10.9 9.22 9.44 9.26 9.Lead 1638 UG/L 351 ND (1.00) U 0.0512 J 0.0485 J 0.0362 J ND (1.00) U 0.0Mercury 1631E UG/L 533 0.0809 0.125 0.0245 0.117 0.0556 0.1Nickel 1638 UG/L 2,840 1,450 111 116 92.0 93.7 92Selenium 1638 UG/L 3,530 584 238 241 621 606 60Silver 1638 UG/L ND (20.0) U ND (2.00) U 0.0413 J 0.0891 J 0.0672 J 0.0695 J 0.0Thallium 1638 UG/L 37.3 23.2 16.8 16.6 15.9 15.8 16Zinc 1638 UG/L 2,130 34.7 15.0 14.4 15.2 15.2 15
J – Result measured above the MDL, but less than the reporting limit. 

L – Sample result between 5x and 10x blank result. 

ND – Not detected (number in parenthesis is the report limit). 

U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

B-3 

Table B-2. Analytical Results for Metals in the Bottom Ash Pond Effluent, Homer City 

Bottom Ash Pond Effluent (SP-4) 

Analyte Method Unit Total Dissolved 

Routine Metals 

Aluminum 200.7 UG/L 323 231 

Antimony 200.7 UG/L 2.68 J 1.62 J 

Arsenic 200.7 UG/L 6.50 J 4.88 J 

Barium 200.7 UG/L 101 106 

Beryllium 200.7 UG/L 0.569 J 0.576 J 

Boron 200.7 UG/L 396 397 

Cadmium 200.7 UG/L 0.117 J 0.174 J 

Calcium 200.7 UG/L 186,000 192,000 

Chromium 200.7 UG/L 0.549 J 0.268 J 

Hexavalent Chromium D1687-92 UG/L NA ND (2.00) U 

Cobalt 200.7 UG/L 2.07 J 1.74 J 

Copper 200.7 UG/L 2.93 J 2.82 J 

Iron 200.7 UG/L 355 106 

Lead 200.7 UG/L ND (50.0) U ND (50.0) U 

Magnesium 200.7 UG/L 31,800 32,600 

Manganese 200.7 UG/L 128 129 

Mercury 245.1 UG/L ND (0.200) U ND (0.200) U 

Molybdenum 200.7 UG/L 19.7 20.2 

Nickel 200.7 UG/L 7.36 J 7.06 J 

Selenium 200.7 UG/L 6.02 6.10 L 

Silver 200.7 UG/L ND (20.0) U ND (20.0) U 

Sodium 200.7 UG/L 106,000 106,000 

Thallium 200.7 UG/L 1.10 J 0.634 J 

Tin 200.7 UG/L ND (30.0) U 1.22 J 

Titanium 200.7 UG/L 6.78 J 0.745 J 

Vanadium 200.7 UG/L 7.85 J 6.98 J 

Yttrium 200.7 UG/L 0.314 J ND (5.00) U 

Zinc 200.7 UG/L 21.6 35.2 

Low-Level Metals – Total 

Antimony 1638 UG/L 1.09 0.990 

Arsenic 1638 UG/L 6.52 5.00 

Cadmium 1638 UG/L 0.0973 J 0.117 J 

Chromium 1638 UG/L 2.67 J 2.28 J 

Hexavalent Chromium 1636 UG/L NA 3.01 

Copper 1638 UG/L 2.37 2.08 
J – Result measured above the MDL, but less than the reporting limit. 

L – Sample result between 5x and 10x blank result. 

ND – Not detected (number in parenthesis is the report limit). 

U – Result below the MDL. (Number shown in parentheses is the reporting limit). 

B-4 

Table B-2. Analytical Results for Metals in the Bottom Ash Pond Effluent, Homer City 

Bottom Ash Pond Effluent (SP-4) 

Analyte Method Unit Total Dissolved 

Lead 1638 UG/L 0.231 J 0.00830 J 

Mercury 1631E UG/L 0.00511 0.00141 

Nickel 1638 UG/L 10.7 10.4 

Selenium 1638 UG/L 5.74 5.16 

Silver 1638 UG/L 0.0313 J ND (0.500) U 

Thallium 1638 UG/L 1.32 1.31 

Zinc 1638 UG/L 24.2 15.0 
Appendix C 

DATA REVIEW NARRATIVES 
Computer Sciences Corporation 

www.csc.com 

6101 Stevenson Avenue 

Alexandria, Virginia 22304 

703.461.2000 Fax 703.461.2020 

MEMORANDUM

DATE: December 7, 2007 

TO: Ron Jordan, Project Officer 

 EPA EAD 

FROM: Maria A. Vargas, Quality Assurance Chemist 

Computer Sciences Corporation 

SUBJECT: Data Review Narrative for Classical Analyses for the Steam Electric Study, Episode 6548 

OVERVIEW

Under EPA Contract Number 68-C-03-058, ProChem Analytical, Inc. submitted classical wet chemistry 

data for eight samples in Episode 6548 with the exception of Nitrate/Nitrite analysis. Six samples were 

analyzed for nitrate and nitrite by Analytical Laboratory Services, Inc., under EPA Contract Number 68-

C-03-068. Sample 70420, identified as FGD influent, was expected to contain a significant and variable 

particulate concentration. EPA and industry representatives were concerned that the variable nature of 

the sample would 1) complicate the collection of a representative sample for both EPA and industry 

analyses and 2) lead to analytical interferences. Therefore, for some classical analyses (those with a phase 

listed in Table 1), the laboratory was directed by EPA to separate the FGD influent sample into an 

aqueous-phase and a solid-phase and analyze each. The two sets of results (filtered aqueous and filtered 

solid phases) are provided in the analytical database, as are calculated total results (derived by combining 

filtered aqueous and filtered solid phase results). 

 

Table 1 provides a complete listing of samples, matrices, descriptions, sampling dates, phases, and the 

required analytes. 

Table 1 - Sample Identifiers, Descriptions, Sampling Dates and Analytes

EPA Sample 

# Matrix Sample Description Sampling Date Phase Analytes

70420 Aqueous SP-1 – FGD Influent 8/22/07 NA 

BOD (SM 5210B), 

Hexavalent Chromium 

(ASTM D1687-92), TSS 

(SM 2540D), TDS (SM 

2540C), HEM (1664A), 

and SGT-HEM (1664A) 

70420 Aqueous SP-1 – FGD Influent 8/22/07 Filtered 

Aqueous 

Chloride (SM 4500-Cl-

 C), 

Total Phosphorus (365.3), 

TKN (SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), and Sulfate 

(ASTM D516-90) 
2

Table 1 - Sample Identifiers, Descriptions, Sampling Dates and Analytes

EPA Sample 

# Matrix Sample Description Sampling Date Phase Analytes

70420 Aqueous SP-1 – FGD Influent 8/22/07 Filtered 

Solid 

Chloride (SM 4500-Cl-

 C), 

Total Phosphorus (365.3), 

TKN (SM 4500-N C), 

Nitrate/Nitrite (1685), 

Ammonia as nitrogen (SM 

4500-NH3 F), and Sulfate 

(ASTM D516-90), and 

Total Solids (2540B) 

70420 Aqueous SP-1 – FGD Influent NA Calculated 

Total 

Chloride (SM 4500-Cl-

 C), 

Total Phosphorus (365.3), 

TKN (SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), and Sulfate 

(ASTM D516-90) 

70421 Aqueous SP-2 – 2nd Stage 

Clarifier 8/23/07 NA 

BOD (SM 5210B), 

Hexavalent Chromium 

(ASTM D1687-92), TSS 

(SM 2540D), TDS (SM 

2540C), Chloride (SM 

4500-Cl-

 C), Total 

Phosphorus (365.3), TKN 

(SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), and Sulfate 

(ASTM D516-90), HEM 

(1664A), and SGT-HEM 

(1664A) 

70422 Aqueous SP-3 – FGD 

Effluent 

8/22/07-

8/23/07 NA 

BOD (SM 5210B), 

Hexavalent Chromium 

(ASTM D1687-92), TSS 

(SM 2540D), TDS (SM 

2540C), Chloride (SM 

4500-Cl-

 C), Total 

Phosphorus (365.3), TKN 

(SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), Sulfate 

(ASTM D516-90), HEM 

(1664A), and SGT-HEM 

(1664A) 
3

Table 1 - Sample Identifiers, Descriptions, Sampling Dates and Analytes

EPA Sample 

# Matrix Sample Description Sampling Date Phase Analytes

70423 Aqueous SP-4 – Bottom Ash 

Effluent 8/23/07 NA 

BOD (SM 5210B), 

Hexavalent Chromium 

(ASTM D1687-92), TSS 

(SM 2540D), TDS (SM 

2540C), Chloride (SM 

4500-Cl-

 C), Total 

Phosphorus (365.3), TKN 

(SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), Sulfate 

(ASTM D516-90), HEM 

(1664A), and SGT-HEM 

(1664A) 

70424 Aqueous SP-5 – FGD 

Effluent Duplicate 8/22/07 NA 

BOD (SM 5210B), 

Hexavalent Chromium 

(ASTM D1687-92), TSS 

(SM 2540D), TDS (SM 

2540C), Chloride (SM 

4500-Cl-

 C), Total 

Phosphorus (365.3), TKN 

(SM 4500-N C), 

Nitrate/Nitrite (353.2), 

Ammonia as nitrogen (SM 

4500-NH3 F), and Sulfate 

(ASTM D516-90) 

70426 Aqueous SP-7 – 2nd Stage 

Clarifier Field Blank 8/23/07 NA Hexavalent Chromium 

(ASTM D1687-92) 

70427 Aqueous SP-8 – FGD 

Effluent Field Blank 8/22/07 NA Hexavalent Chromium 

(ASTM D1687-92) 

70428 Aqueous SP-9 – Bottom Ash 

Effluent Field Blank 8/23/07 NA Hexavalent Chromium 

(ASTM D1687-92) 

 NA= Not applicable. In the Phase column, only one result exists in the EPA database for this sample/analyte 

 combination. 

These data have been reviewed in accordance with CSC’s Data Review Guidelines for Classical Wet 

Chemistry Analyses (DR-02 Revision 2, September 1, 2007) and with the specifications listed in the 

contract. All data are of acceptable quality with the qualifiers described below and detailed in the data 

review summary table (Table 2). 

SUMMARY 

All samples were analyzed within the contract-specified holding times for all classical wet chemistry 

parameters specified in the sampling and analysis plan. The calibration and continuing calibration 

standards were successfully analyzed. Laboratory blanks were performed for each analysis, and there was 

no contamination detected above the laboratory reporting limit. Field blanks were analyzed for 

hexavalent chromium and were found to contain no hexavalent chromium above the ML. The quality 

control samples (QC), including the ongoing precision and recovery sample (OPR) and matrix 

spike/matrix spike duplicate (MS/MSD) samples, demonstrated that laboratory performance for these 
4

analyses was acceptable with the exception of the samples described below. The MS/MSDs analyses 

were performed on numerous samples and are detailed below. 

DATA ISSUES 

Nitrate and Nitrite 

The matrix spike (MS) recovery for sample 70424 (96%) was within the contract specified acceptance 

criteria (75-125%). The related matrix spike duplicate (MSD) recovery (73%) was outside the acceptance 

criteria. The relative percent difference (RPD) (14%) between the MS and MSD in sample 70424 was 

within the acceptance criteria of 20%. CSC considers the nitrate/nitrite results in sample 70424 to be of 

acceptable quality, but may be a minimum value. 

Ammonia as Nitrogen, Total Phosphorus, and TSS 

The relative percent difference (RPD) between field duplicate samples 70422 (FGD effluent) and 70424 

(FGD effluent duplicate) for the following analytes were: ammonia as nitrogen (44%), total phosphorus 

(78%) and TSS (100%). CSC does not routinely qualify results based on field duplicate RPD. 

TECHNICAL NOTES 

BOD (Biochemical Oxygen Demand) 

Samples 70420, 70421, 70422, and 70424 did not meet the contract-specified minimum dissolved oxygen 

depletion of 2.0 mg/L, indicating that less dilute sample aliquots should have been analyzed. The samples 

were re-prepared using less dilute aliquots, however, the 48-hour holding time had expired. Therefore, 

CSC recommends reporting the original results for these samples in the database as not detected at the 

lower limit of the measurement range, adjusted for dilution. 

HEM/SGT-HEM 

Although HEM/SGT-HEM analyses were requested for samples 70420, 70421, 70422, and 70423, SGTHEM analysis was not required because HEM was not detected in these samples. 

Nitrate/Nitrite 

The ICV, CCV, ICB, and CCB analyses were not performed in the proper sequence (blanks were run 

before verification samples) for the nitrate/nitrite analytes. All calibration verification standards and 

blanks, however, met contract specifications. Therefore, CSC considers the sample data acceptable 

without qualification. 

QC Samples 

The laboratory performed QC sample analyses on the following: 

• 70420: chloride, sulfate, ammonia as nitrogen, TKN, and total phosphorus 

• 70422: BOD, hexavalent chromium, TSS, Hem, chloride, sulfate, TDS, ammonia as nitrogen, 

TKN, and total phosphorus 

• 70423: BOD, hexavalent chromium, TSS, Hem, chloride, sulfate, TDS, ammonia as nitrogen, 

TKN, and total phosphorus. 

• 70424: nitrate/nitrite 
5

Phase Separation and Calculations 

As described in the phase separation document, EPA’s contract laboratory was asked to measure and 

record the following data as part of the phase separation process: 

• Original sample weight 

• Original sample volume 

• Net weight of solid phase on the filter 

• Filtrate weight 

• Filtrate volume 

Some of these variables were required for used to calculate a total result; there should be one set of these 

records for each of Group I and Group II analyses. The laboratory failed to provide those items listed in 

bold above for Group 1 analyses and all of the required elements for the Group II analyses. 

CSC calculated the total results for the FGD Influent sample using the following formula: 

For Group I, several variables were not recorded by the laboratory as requested—most importantly, the 

original sample volume and filtrate volume. In discussion with the lab, CSC was able to calculate the 

missing variables based on other information that the laboratory was able to provide including the original 

sample density, original sample weight, and the solid phase weight. This series of calculations are as 

follows and detailed in the phase separation data elements table (Table 3): 

• Original sample weight = (Original sample volume) x (Original sample density) 

• Filtrate weight = (Original sample weight) - (Solid-phase weight) 

• Filtrate volume = (Filtrate weight) / (Original sample density) 

For Group II, because none of the required elements were recorded, Group I volumes and weights were 

used to generate the “Calculated Total”. CSC believes because there was a equalization tank at the FGD 

influent sampling point, Group I and II sample bottles should be very similar in particulate content; the 

Group I volumes and weights therefore may be applied to Group II results. However, because this still 

involves some level of uncertainty, calculated total data for Group II analyses will be qualified as 

estimated for sample 70420. 

In generating the classicals “Calculated Total” results for the Steam Electric Study, CSC used all values 

greater than the ML. However, if any concentration was affected by contamination in an associated blank 

at less than 5 times the associated blank result, it was changed to a zero before going through the 

calculation, per CSC's data review protocols. Negative values submitted by the laboratory were not used 

in the calculations. 

Please note that the results for the various phases will be labeled in the PROCEDUR field of the EPA 

database as “FILTERED AQUEOUS”, “FILTERED SOLID (WET WEIGHT)”, and “CALCULATED 

TOTAL”. 

Minimum Levels 

When two results are mathematically combined to obtain a Calculated Total result, CSC will report the 

larger of the two MLs associated with each result as the Calculated Total ML. 

Vol. L

(Conc. mg/L x Vol. L) (Conc. mg/kg Wt. kg) Total SampleConcentration mg/L

original sample

Filtrate Filtrate + solid phase × solid phase =
6

Percent Solids

The percent solid result is provided in Table 3, if desired, to convert solid phase wet weight basis values 

to dry weight results, and was not used to generate the “Calculated Total” results. 

If you have any questions regarding the analyses of these samples or the review of these data, please 

contact Barbara Beard by telephone at (703) 461-2154, by facsimile at (703) 461-8056, or by email at 

bbeard2@csc.com. 

cc: Brian D’Amico, EPA 

Marla Smith, EPA 

 Beverly Randolph, EPA 

Nelson Andrews, EPA 

 Brian Englert, EPA 

Deb Bartram, ERG 

TJ Finseth, ERG 

Lynn Walters, CSC 

Barbara Beard, CSC 

Table 2

Data Review Summary Table 

Episode: 6548 Analysis: Classicals 

Industry: Steam Electric Study Reviewer: Maria A. Vargas 

Sample Analyte Action Reason CSC Qual Level

70420 

Ammonia as 

nitrogen, 

Nitrate/Nitrite, 

TKN, Total 

Phosphorus 

Estimated value Estimated value used 

in calculation of total NA See database 

70424 Nitrate/Nitrite Minimum value 

MSD Recovery below 

the contract-specified 

criteria 

NA 36 mg/L 

NA= Not Applicable 
7

 Table 3 

 Phase Separation Data Elements 

Episode: 6548 Analysis: Classicals 

Industry: Steam Electric Study Reviewer: Maria A. Vargas 

Group number I II 

Sample number 70420 70420 

Original sample vol (mL) 997.01a

 997.01b 

Net weight of solid phase on the filter (g) 24.73 24.73 b

Density (g/mL) 1.004 1.004 b

Original sample weight (g) 1001 1001 b

Filtrate weight (g) 976.27a

 976.27b 

Filtrate volume (mL) 972.38a

 972.38b 

Percent Solid (of solid phase) (%) 61 62 

 

a

Derived value. Calculated using lab measured results (if available), or otherwise estimated

b Volumes and weights from Group I bottle because measurements were not performed on the Group II 

bottle. 
Computer Sciences Corporation 

www.csc.com

MEMORANDUM 

DATE: December 7, 2007 

TO: Ron Jordan, Work Assignment Manager 

 EPA EAD 

FROM: Lisa White, Quality Assurance Chemist 

Computer Sciences Corporation 

SUBJECT: Revised Data Review Narrative for Total and Dissolved Metals Analyses for the Steam

Electric Study, Episode 6548 

Under EPA contract number 68-C-03-044, ProChem Analytical submitted data for the analysis of total 

and dissolved metals by EPA Method 200.7 and mercury by Method 245.1 in Episode 6548. Eight 

aqueous samples in this episode were analyzed for total and dissolved metals. 

Sample 70420, identified as FGD Influent, was expected to contain a significant and variable particulate 

concentration. EPA and Industry representatives were concerned that the variable nature of the sample 

would 1) complicate the collection of a representative sample for both EPA and Industry analyses and 2) 

lead to analytical interferences. Therefore, the laboratory was directed by EPA to separate the FGD 

Influent sample into an aqueous phase and a solid phase, and analyze each for mercury. The two sets of 

results (filtered aqueous and filtered solid phases) are provided in the analytical database, including the 

calculated total result (derived by combining filtered aqueous and filtered solid phase results). Please 

note that the total metals results for the FGD Influent sample will be delivered under a separate Data 

Review Narrative. 

Table 1 provides a list of samples, matrices, descriptions, sampling dates, phase, and the required 

analytical methods.

Table 1 - Sample Identifiers, Descriptions, Sampling Dates, and Analysis Methods

EPA 

Sample # Matrix Sample Description Sampling

Date Phase Methods

Dissolved 200.7, 245.1

8/22/07 Filtered Solid Phase

Filtered Aqueous Phase

70420 Aqueous SP-1 FGD Influent

NA Calculated Total

245.1 

Total 

70421 Aqueous SP-2 2nd Stage Clarifier 8/23/07 

Dissolved 

200.7, 245.1

Total 70422 Aqueous SP-3 FGD Effluent 8/22/07 

Dissolved 

200.7, 245.1

Total 

70423 Aqueous SP-4 Bottom Ash Effluent 8/23/07 

Dissolved 

200.7, 245.1

Total 

70424 Aqueous SP-5 FGD Effluent Duplicate 8/22/07 

Dissolved 

200.7, 245.1

6101 Stevenson Avenue 

Alexandria, Virginia 22304 

703.461.2000 Fax 703.461.2020
Table 1 - Sample Identifiers, Descriptions, Sampling Dates, and Analysis Methods

EPA 

Sample # Matrix Sample Description Sampling

Date Phase Methods

Total 

70426 Aqueous 

SP-7 2nd Stage Clarifier Field 

Blank 8/23/07 

Dissolved 

200.7, 245.1

Total 

70427 Aqueous 

SP-8 FGD Effluent Field 

Blank 8/22/07 

Dissolved 

200.7, 245.1

Total 

70428 Aqueous 

SP-9 Bottom Ash Effluent

Field Blank 8/23/07 

Dissolved 

200.7, 245.1

NA = Not Applicable 

These data have been reviewed in accordance with CSC's Data Review Guidelines for Metals Analyses 

(November 2004); the EAD contract; and with the specifications listed in EPA Methods 200.7 (Rev. 5.0), 

and 245.1 (03/83). All data are of acceptable quality with the qualifiers described below and detailed in 

the data review summary table (Table 2). 

 

SUMMARY 

All samples were successfully analyzed within the method-specified holding times, with the exceptions 

noted below for mercury. The method detection limit (MDL) studies were performed and met the 

contract-specified criteria. The aqueous initial precision and recovery (IPR) analysis was performed and 

met the contract-specified criteria. The solid phase initial precision and recovery (IPR) analysis was also 

performed and met the contract-specified criteria. 

Calibration curves, calibration standards, and calibration blanks were successfully analyzed, with the 

exceptions noted below. Preparation blanks performed for each analysis detected no contamination above 

the laboratory’s reporting limits. Field and filter blank analyses detected no analytes above the ML, with 

the exceptions noted below. QC samples, including ongoing precision and recovery (OPR) samples, 

matrix spike (MS) samples, matrix spike duplicate (MSD) samples, and laboratory serial dilution samples 

demonstrated that laboratory performance for these analyses was acceptable, with the exception of the 

issues described below and summarized in Table 2. The MS/MSD analyses were performed on samples 

70420, 70422, and 70423. 

DATA ISSUES

Method and Analytical Blanks

Several analytes were detected in the preparation blanks (PBs), initial calibration blanks (ICBs), and 

continuing calibration blanks (CCBs) associated with the samples in this episode at concentrations greater 

than the respective MDLs, but less than the method-specified MLs. The data quality is affected as 

follows: 

 • Sample Results Greater than Five Times but Less than Ten Times Blank Results: CSC considers 

these results to be of acceptable quality, but they may be maximum values. The affected samples 

and analytes are as follows: dissolved selenium in sample 70423. 

• Sample Results Greater than Ten Times Blank Results or Analyte Not Detected in Sample: CSC 

does not consider the presence of the analyte in the blank to adversely affect the data in cases 

where the sample results are greater than ten times the associated blank results or where the 

2 
3

analyte is not detected in associated samples. Several samples fall into this category, but because 

CSC considers such data to be acceptable without qualification, these cases do not merit further 

detail. 

Holding Times - Mercury 

Due to severe matrix interferences in the original analyses for mercury, the laboratory redigested and 

reanalyzed several samples one day past the contract-specified holding time. The affected sample results 

are as follows: filtered aqueous phase and dissolved mercury for sample 70420; total and dissolved 

mercury for samples 70422 and 70424. In all cases, mercury was not detected in the sample. CSC does 

not qualify results for holding time failures when the affected analytes are not detected in the samples. 

Matrix Performance 

MS/MSD and Serial Dilution analyses were performed on samples 70420, 70422, and 70423. 

70420

The percent recoveries for dissolved barium in the matrix spike (MS) and matrix spike duplicate (MSD) 

for sample 70420 were below contract-specified criteria of 75% (48% and 51% respectively). CSC 

recommends that the result for dissolved barium in sample 70420 be considered of acceptable quality but 

may be a minimum value. 

 

The percent recovery for dissolved selenium (133%) in the MSD for sample 70420 was above the 

contract-specified criteria of 125%. In addition, the serial dilution percent difference for dissolved 

selenium (29%) in dissolved sample 70420 was above the contract-specified criteria of 10%. The 

combination of spike recovery failure and serial dilution failure indicates severe matrix interferences. 

Therefore, CSC recommends that the result for dissolved selenium in sample 70420 be considered an 

estimated value. 

The percent recoveries for dissolved antimony (135% and 139%) in the MS and MSD for sample 70420 

were above the contract-specified criteria of 125%. In addition, the serial dilution percent difference 

(130%) was above the contract-specified criteria of 10%. Because antimony was not detected in 

dissolved sample 70420, CSC recommends that the result for antimony be included in the database 

without qualification. 

The percent recoveries for dissolved arsenic (129%) and silver (127%) in the MSD for sample 70420 

were above the contract-specified criteria of 125%. Because arsenic and silver were not detected in 

dissolved sample 70420, CSC recommends that the results for arsenic and silver be included in the 

database without qualification. 

The serial dilution percent differences for several analytes were above the contract-specified criteria of 

10% in sample 70420. These instances are as follows: dissolved cadmium (14%), copper (47%), 

molybdenum (43%), and thallium (100%) in sample 70420. In these cases, MS/MSD percent recoveries 

were within acceptable criteria. CSC recommends that the results for these analytes be included in the 

database without qualification.

70422

The percent recoveries for dissolved barium in the matrix spike (MS) and matrix spike duplicate (MSD) 

for sample 70422 were below contract-specified criteria of 75% (21% and 64% respectively). In addition, 
4

the relative percent difference (RPD) between the matrix spike and matrix spike duplicate for dissolved 

barium in sample 70422 (87%) was above contract-specified criteria of 20%. CSC recommends that the 

result for dissolved barium in sample 70422 be considered an estimated value. 

The percent recoveries for total barium in the MS and MSD for sample 70422 (44% and 50% 

respectively) were below contract-specified criteria of 75%. CSC recommends that the result for total 

barium in sample 70422 be considered of acceptable quality but may be a minimum value. 

The percent recovery for dissolved iron in the MS for sample 70422 (68%) was below the contractspecified criteria of 75%. CSC recommends that the result for dissolved iron in sample 70422 be 

considered of acceptable quality but may be a minimum value. 

The percent recovery for dissolved selenium (130%) in the MSD for sample 70422 was above the 

contract-specified criteria of 125%. In addition, the serial dilution percent difference for selenium (20%) 

was above the contract-specified criteria of 10%. The combination of spike recovery failure and serial 

dilution failure indicates severe matrix interferences. Therefore, CSC recommends that the result for 

dissolved selenium in sample 70422 be considered an estimated value. 

The percent recoveries for dissolved arsenic (138%), silver (126%), and yttrium (127%) in the MSD for 

sample 70422 were above the contract-specified criteria of 125%. In addition, the RPD between the MS 

and MSD for dissolved arsenic (36%) was above the contract-specified criteria of 20%. Because arsenic, 

silver, and yttrium were not detected in dissolved sample 70422, CSC recommends that the results be 

included in the database without qualification. 

The percent recovery for dissolved tin (25%) in the MS for sample 70422 was below the contractspecified criteria of 75%. In addition, the RPD between the MS and MSD for dissolved tin (119%) was 

above the contract-specified criteria of 20%. Because tin was not detected in dissolved sample 70422, 

CSC recommends that the result for tin be included in the database without qualification. 

The relative percent differences between the MS and MSD for dissolved lead (21%) and titanium (21%) 

were above the contract-specified criteria of 20%. Because these analytes were not detected in dissolved 

sample 70422, CSC recommends that the results be included in the database without qualification. 

The serial dilution percent differences for several analytes were above the contract-specified criteria of 

10% in sample 70422. These instances are as follows: 

• Dissolved cadmium (21%), copper (43%), and zinc (100%) in sample 70422; 

• Total cadmium (19%), copper (18%), and selenium (18%) in sample 70422. 

In these cases, MS/MSD percent recoveries were within acceptable criteria. CSC recommends that the 

results for these analytes be included in the database without qualification.

70423

The serial dilution percent differences for total aluminum (37%) and titanium (19%) were above the 

contract-specified criteria of 10% in sample 70423. In these cases, MS/MSD percent recoveries were 

within acceptable criteria. CSC recommends that the results for these analytes be included in the database 

without qualification.
5

Field Duplicates 

The relative percent difference (RPD) between the dissolved iron results for samples 70422 (FGD 

effluent) and 70424 (FGD effluent duplicate) was 38%. For sample 70422 (FGD effluent), antimony was 

detected at a level below the ML, but was detected slightly above the ML for total sample 70424 (FGD 

effluent duplicate). CSC does not routinely qualify results based on field duplicate RPD. 

Field Blanks/Filter Blanks 

Several analytes were detected at concentrations above the contract-specified minimum levels. These 

instances are summarized as follows: 

• Barium, calcium, magnesium, molybdenum, and selenium were detected in the dissolved field 

blank sample 70427; 

• Calcium was detected in the total field blank sample 70427; 

• Calcium and magnesium were detected in the total field blank sample 70428. 

Per EPA request, CSC does not qualify sample results based on field and filter blanks results. 

TECHNICAL NOTES 

Phase Separation and Calculations 

As described in the phase separation document, EPA’s contract laboratory was asked to measure and 

record the following data as part of the phase separation process: 

• Original sample weight 

• Original sample volume 

• Net weight of solid phase on the filter 

• Filtrate weight 

• Filtrate volume 

The laboratory failed to provide those items listed in bold above. 

CSC calculated the total mercury result for sample 70420 (FGD Influent) using the following formula: 

Vol. L

(Conc. μg/L x Vol. L) (Conc. mg/kg 1000 μg/mg x Wt. kg) Total Sample Concentration μg/L

original sample

Filtrate Filtrate + solid × solid =

Phase separation Data Elements are summarized in Table 3. 

In the generation of the Calculated Total result, CSC included values reported by the laboratory that were 

greater than the MDL but less than the ML. However, if any concentration was affected by

contamination in an associated blank at less than 5 times the associated blank result, it was changed to a 

zero, per CSC's data review protocols before going through the calculation. Negative values submitted by

the laboratory were not used in the calculations. 

Because the laboratory provided only the solid phase weight, CSC estimated the original sample volume 

to be 500 mL, based on the bottle size, and because the laboratory reported that the bottles were full upon 
6

receipt. The filtrate volume was calculated using this estimated original volume, solid phase weight, and 

the density of the original sample measured by the laboratory. This series of calculations follows: 

• Original sample weight = (Original sample volume) x (Original sample density) 

• Filtrate weight = (Original sample weight) - (Solid weight) 

• Filtrate volume = (Filtrate weight) / (Original sample density) 

Additionally, CSC requested that the laboratory measure the volume of a 500-mL bottle of the type used 

for these samples, to further refine the sample volume estimate. A discussion of the uncertainty 

introduced by the volume assumption is included below. 

• According to the laboratory, a 500-mL bottle filled to the rim holds about 510 mL (to the nearest 

mL). 

• Allowing for some variability among the 500-mL bottles and the levels to which each was filled in 

the field, we assume that a “full” bottle holds 500 mL ± 10 mL. 

• Recalculating the results from Episode 6548 using 510 mL as the original volume yields results that 

are 4 % higher than those calculated assuming 490 mL. 

• Therefore, for the metals results in Episode 6548, the volume estimation introduces an error of ± 4 %. 

That difference is well within the expected analytical uncertainty and at least 5 times lower than 

typical acceptance limits for laboratory duplicate analyses (i.e., 20%). 

As a result, all calculated total data for mercury will be qualified as estimated for sample 70420. 

Please note that the results for the various phases will be labeled in the PROCEDUR field of the EPA 

database as “FILTERED AQUEOUS”, “FILTERED SOLID (WET WEIGHT)”, and “CALCULATED 

TOTAL”. 

Minimum Levels 

When two results are mathematically combined to obtain a Calculated Total result, CSC will report the 

larger of the two MLs associated with each result as the Calculated Total ML.

Due to severe matrix interferences, the laboratory analyzed several samples at 50-fold dilutions for 

mercury. The affected sample results are as follows: filtered aqueous phase and dissolved mercury for 

sample 70420; total and dissolved mercury for samples 70421, 70422 and 70424. Reporting limits for 

these results have been adjusted for dilution. 

Percent Solids 

For sample 70420, a percent solid evaluation was performed and is summarized in Table 3. The percent 

solid result is provided only for the use by EPA to convert solid phase wet weight basis values to dry 

weight results. The percent solid was not used in the generation of the “CALCULATED TOTAL”. 

If you have any questions regarding the analyses of these samples or the review of these data, please 

contact Barbara Beard by telephone at (703) 461-2154, by facsimile at (703) 461-8056, or by email at 

bbeard2@csc.com.

cc: Brian D’Amico, EPA 

Beverly Randolph, EPA 
7

Marla Smith, EPA 

Nelson Andrews, EPA 

Brian Englert, EPA 

 Deb Bartram, ERG 

TJ Finseth, ERG 

Lynn Walters, CSC 

 Barbara Beard, CSC 
8

Table 2 

Data Review Summary Table

Episode: 6548 Analysis: Metals

Industry: Steam Electric Study Reviewer: Lisa White 

Sample Analyte Action Reason CSC Qual Level

70420 dissolved Ba Minimum Value MS and MSD %R below 

contract-specified criteria NA See Database 

70420 dissolved Se Estimated Value 

Serial Dilution %D above 

contract-specified criteria; 

MSD %R above contractspecified criteria 

NA See Database 

70420 

calculated total Hg Estimated Value Estimated value used in 

calculation of total NA See Database 

70422 dissolved Ba Estimated Value 

MS/MSD %R below 

contract-specified criteria; 

RPD between MS and 

MSD above contractspecified criteria 

NA See Database 

70422 total Ba Minimum Value MS/MSD %R below 

contract-specified criteria NA See Database 

70422 dissolved Fe Minimum Value MS %R below contractspecified criteria NA See Database 

70422 dissolved Se Estimated Value 

Serial Dilution %D above 

contract-specified criteria; 

MSD %R above contractspecified criteria 

NA See Database 

70423 dissolved Se Maximum Value Sample result >5x but 

<10x blank result NA See Database 

NA= Not applicable 

ND= Not detected 
9

Table 3 

 Phase Separation Data Elements 

 Episode: 6548 Analysis: Metals 

 Industry: Steam Electric Study Reviewer: Lisa White 

Sample number 70420 

Original sample vol (mL) 500a

Net weight of solid phase on the filter (g) 8.39 

Density (g/mL) 1.004 

Original sample weight (g) 502 

Filtrate weight (g) 494 

Filtrate volume (mL) 492 

Percent Solid (of solid phase) (%) 63 

 

 a

 Derived value. Calculated using lab measured results (if available), or otherwise estimated 

 
Computer Sciences Corporation 

www.csc.com

MEMORANDUM 

DATE: January 08, 2008 

TO: Ron Jordan, Work Assignment Manager 

 EPA EAD 

FROM: Lisa White, Quality Assurance Chemist 

Computer Sciences Corporation 

SUBJECT: Data Review Narrative for Total Metals Analyses for the Steam Electric Study, Episodes 

6547 and 6548

Under EPA contract number 68-C-03-044, ProChem Analytical submitted data for the analysis of total 

metals by EPA Method 200.7 for aqueous sample 70320 in Episode 6547 and aqueous sample 70420 in

Episode 6548. Because influent samples for this study were expected to be highly variable in solids 

content, EPA chose to obtain results for the solid phase as well. The solid phase results for sample 70320 

and 70420 were not directly analyzed, but rather calculated from total, dissolved, and TSS results. 

Please note that the results for mercury by Method 245.1 and dissolved metals by Method 200.7 for these 

samples were previously delivered under a separate Data Review Narrative. 

Table 1 provides a list of samples, episodes, matrices, descriptions, sampling dates, phase, and the 

required analytical methods.

Table 1 - Sample Identifiers, Descriptions, Sampling Dates, and Analysis Methods

EPA 

Sample #

Episode 

# Matrix Sample Description Sampling

Date Phase Method

7/25/07 Total

70320 6547 Aqueous FGD Influent

NA Calculated Solid

200.7 

8/22/07 Total

70420 6548 Aqueous FGD Influent

NA Calculated Solid

200.7 

NA = Not Applicable 

These data have been reviewed in accordance with CSC's Data Review Guidelines for Metals Analyses 

(November 2004); the EAD contract; and with the specifications listed in EPA Methods 200.7 (Rev. 5.0). 

All data are of acceptable quality with the qualifiers described below and detailed in the data review 

summary table (Table 2). 

 

SUMMARY 

All samples were successfully analyzed within the method-specified holding times. The method detection

limit (MDL) studies and initial precision and recovery (IPR) analyses were performed and met the 

contract-specified criteria. Calibration curves, calibration standards, and calibration blanks were 

successfully analyzed. Preparation blanks performed for each analysis detected no contamination above 

the laboratory’s reporting limits. QC samples, including ongoing precision and recovery (OPR) samples, 

matrix spike (MS) samples, matrix spike duplicate (MSD) samples, and laboratory serial dilution samples 

demonstrated that laboratory performance for these analyses was acceptable, with the exception of the 

6101 Stevenson Avenue 

Alexandria, Virginia 22304 

703.461.2000 Fax 703.461.2020
2

issues described below and summarized in Table 2. The MS/MSD analyses were performed on sample 

70420. 

DATA ISSUES

Method and Analytical Blanks

Several analytes were detected in the preparation blanks (PBs), initial calibration blanks (ICBs), and 

continuing calibration blanks (CCBs) associated with the samples in this episode at concentrations greater 

than the respective MDLs, but less than the method-specified MLs. The data quality is affected as 

follows: 

• Sample Results Greater than Ten Times Blank Results or Analyte Not Detected in Sample: CSC 

does not consider the presence of the analyte in the blank to adversely affect the data in cases 

where the sample results are greater than ten times the associated blank results or where the 

analyte is not detected in associated samples. Several samples fall into this category, but because 

CSC considers such data to be acceptable without qualification, these cases do not merit further 

detail. 

Matrix Performance 

MS/MSD and Serial Dilution analyses were performed on samples 70420. 

The percent recoveries for total barium in the MS and MSD (18% and 9% respectively) for sample 70420 

were below contract-specified criteria of 75%. In addition, the serial dilution percent difference for total 

barium (16%) was above the contract-specified criteria of 10%. The combination of spike recovery 

failure and serial dilution failure indicates severe matrix interferences. Therefore, CSC recommends that 

the result for total barium in sample 70420 be considered an estimated value. 

 

The percent recovery for total titanium (126%) in the MS for sample 70420 was slightly above the 

contract-specified criteria of 125%. In addition, the serial dilution percent difference (19%) was above the 

contract-specified criteria of 10%. The combination of spike recovery failure and serial dilution failure 

indicates severe matrix interferences. Therefore, CSC recommends that the result for total titanium in 

sample 70420 be considered an estimated value. 

The percent recovery for total nickel (73%) in the MSD for sample 70420 was slightly below the 

contract-specified criteria of 75%. In addition, the serial dilution percent difference (16%) was above the 

contract-specified criteria of 10%. The combination of spike recovery failure and serial dilution failure 

indicates severe matrix interferences. Therefore, CSC recommends that the result for total nickel in 

sample 70420 be considered an estimated value. 

The percent recovery for total selenium (47%) in the MSD for sample 70420 was below the contractspecified criteria of 75%. CSC recommends that the result for total selenium in sample 70420 be 

considered of acceptable quality, but may be a minimum value. 

Total thallium was not recovered in the MS or MSD for sample 70420. In addition, the analyte was not 

detected in the unspiked sample. The laboratory suspected that the increased solids in the sample 

(chloride in particular) were likely the cause. Zero percent recoveries in the matrix spike samples indicate 

significant methodological problems that preclude successful analysis of thallium. Therefore, CSC 

recommends that the results for total thallium and calculated solid thallium in sample 70420 be excluded 

from the database. 
3

The serial dilution percent differences for several analytes were above the contract-specified criteria of 

10% in sample 70420. These instances are as follows: total chromium (14%), cobalt (17%), copper 

(15%), lead (12%), molybdenum (12%), sodium (11%), vanadium (26%), and zinc (17%). In these cases, 

MS/MSD percent recoveries were within acceptable criteria. CSC recommends that the results for these 

analytes be included in the database without qualification.

 TECHNICAL NOTES 

Solid Phase Calculations 

CSC calculated the solid phase results using the following formula:

ug mg

mg kg

TSS mg L

Conc g L Conc g L

original sample

Total Dissolved

10 /

10 /

/

( . / . / ) Solid phase concentration (mg/kg) 3

6

× − = μ μ

In the generation of the Calculated Solid result, at EPA's request, CSC included Total and Dissolved 

concentrations that were greater than the MDL but less than the ML unless both factors in the calculations 

were less than the ML. However, if any concentration was affected by contamination in an associated 

blank at less than 5 times the associated blank result, it was changed to a zero before going through the 

calculation, per CSC's data review protocols. Negative values submitted by the laboratory were not used 

in the calculations. 

The results for the various phases will be labeled in the PROCEDUR field of the EPA database as 

“DISSOLVED”, “TOTAL”, and “CALCULATED SOLID (DRY WEIGHT)”. 

The TSS result for sample 70320 in Episode 6547 is 4970 mg/L. The TSS result for sample 70420 in 

Episode 6548 is 13300 mg/L. 

Minimum Levels 

When two results are mathematically combined to obtain a Calculated Solid result, CSC will report the 

larger of the two MLs associated with each result as the Calculated Solid ML. 

In order to alleviate expected matrix effects, the laboratory performed a 2-fold dilution on sample 70420 

in Episode 6548. MLs are adjusted appropriately.

If you have any questions regarding the analyses of these samples or the review of these data, please 

contact Barbara Beard by telephone at (703) 461-2154, by facsimile at (703) 461-8056, or by email at 

bbeard2@csc.com.

cc: Brian D’Amico, EPA Deb Bartram, ERG 

Beverly Randolph, EPA TJ Finseth, ERG 

Marla Smith, EPA Lynn Watlers, CSC 

Nelson Andrews, EPA Barbara Beard, CSC 

Brian Englert, EPA 

 
4

Table 2 

Data Review Summary Table

Episode: 6547, 6548 Analysis: Metals

Industry: Steam Electric Study Reviewer: Lisa White 

Sample Analyte Action Reason CSC Qual Level

70420 Total Ba Estimated Value 

MS and MSD %R below 

contract-specified criteria; 

Serial Dilution %D above 

contract-specified criteria 

NA See Database 

70420 

Calculated solid Ba Estimated Value 

Dissolved component is a 

Minimum Value; 

Total component is an 

Estimated Value 

NA See Database 

70420 Total Tl Exclude Zero %R in MS and MSD EXCLUDE NA 

70420 

Calculated Solid Tl Exclude Not Calculable EXCLUDE NA 

70420 Total Ti Estimated Value 

MS %R above contractspecified criteria; 

Serial Dilution %D above 

contract-specified criteria 

NA See Database 

70420 

Calculated solid Ti Estimated Value Total component is an 

Estimated Value NA See Database 

70420 Total Ni Estimated Value 

MSD %R below contractspecified criteria; 

Serial Dilution %D above 

contract-specified criteria 

NA See Database 

70420 

Calculated solid Ni Estimated Value Total component is an 

Estimated Value NA See Database 

70420 Total Se Minimum Value MSD %R below contractspecified criteria NA See Database 

70420 

Calculated solid Se Estimated Value 

Total component is a 

Minimum value; 

 Dissolved component is 

an Estimated Value 

NA See Database 

NA= Not applicable 

 
Computer Sciences Corporation 

www.csc.com 

6101 Stevenson Avenue 

Alexandria, Virginia 22304 

703.461.2000 Fax 703.461.2020 

MEMORANDUM 

DATE: December 20, 2007 

TO: Ron Jordan, Work Assignment Manager 

 EPA EAD 

FROM: Cris Robinson, Quality Assurance Chemist 

Computer Sciences Corporation 

SUBJECT: Data Review Narrative for Trace Metals Analyses for the Steam Electric Study, Episode 

6548 

Under EPA contract number 68-C-03-046, Battelle Marine Sciences submitted data for the analyses of 

trace metals. All nine aqueous samples in this episode were analyzed for total mercury (Hg) by Method 

1631E and total metals including antimony (Sb), arsenic (As), cadmium (Cd), copper (Cu), chromium 

(Cr), lead (Pb), nickel (Ni), selenium (Se), silver (Ag), thallium (Tl), and zinc (Zn) by Method 1638 (ICPMS). Seven of the nine (FGD and Bottom Ash effluents; Clarifier; FGD effluent duplicate; FGD effluent, 

Bottom Ash effluent, and Clarifier field blanks) were analyzed for hexavalent chromium by Method 1636. 

Several samples were analyzed for dissolved metals as well as total. Because influent samples for this 

study were expected to be highly variable in solids content, EPA chose to obtain results for this phase as 

well. The solid-phase results for sample 70420 were not directly analyzed, but rather calculated from 

total, dissolved, and TSS results.

Table 1 - Sample Identifiers, Descriptions, Sampling Dates, and Analysis Methods 

EPA Sample 

# Matrix Sample Description Sampling Date Phase Methods

Total 1631E, 

1638 

8/22/07 

Dissolved 1631E, 

1638 70420 Aqueous SP-1 FGD influent 

NA Calculated 

Solid 

1631E, 

1638 

Total 1631E, 

1638 

Dissolved 1631E, 

1638 

70421 Aqueous SP-2 2nd Stage Clarifier 8/23/07 

NA 1636 

Total 1631E, 

1638 

Dissolved 1631E, 

1638 

70422 Aqueous SP-3 FGD Effluent 8/22/07 

NA 1636 

 

 
2 

Table 1 - Sample Identifiers, Descriptions, Sampling Dates, and Analysis Methods 

EPA Sample 

# Matrix Sample Description Sampling Date Phase Methods

Total 1631E, 

1638 

Dissolved 1631E, 

1638 

70423 Aqueous SP-4 Bottom Ash Effluent 8/23/07 

NA 1636 

Total 1631E, 

1638 

Dissolved 1631E, 

1638 

70424 Aqueous SP-5 FGD Effluent Duplicate 8/22/07 

NA 1636 

Total 1631E, 

1638 70425 Aqueous SP-6 FGD Influent Field Blank 8/22/07 

Dissolved 1638 

Total 1631E, 

1638 

Dissolved 1638 70426 Aqueous SP-7 2nd Stage Clarifier Field Blank 8/23/07 

NA 1636 

Total 1631E, 

1638 

Dissolved 1638 70427 Aqueous SP-8 FGD Effluent Field Blank 8/22/07 

NA 1636 

Total 1631E, 

1638 

Dissolved 1638 70428 Aqueous SP-9 Bottom Ash Effluent Field 

Blank 8/23/07 

NA 1636 

NA = Not applicable

These data have been reviewed in accordance with CSC's Data Review Guidelines for Metals Analyses 

(November 2004), with the EAD contract, and with the specifications listed in EPA Methods 1631E (Aug 

2002), 1636 (Jan 1996), and 1638 (Jan 1996). All data are of acceptable quality with the qualifiers 

described below and detailed in the data review summary table (Table 2). 

SUMMARY

All nine samples were successfully analyzed within the method-specified holding times, and initial 

precision and recovery (IPR) analyses and method detection limit (MDL) studies were acceptably 

performed. All QC samples, including ongoing precision and recovery samples (OPR), matrix spike and 

matrix spike duplicate (MS/MSD) samples, and quality control samples (QCS) were within method 

specified criteria, with the exceptions described below. The MS/MSD analyses were performed on 

samples 70420, 70422, and 70423. Calibration curves and calibration verification standards were 

successfully analyzed. 
3

All calibration and preparation blanks were free of contamination above the report limit (minimum level 

or ML). No analytes were detected at levels above the reporting limit in the field blanks, with the 

exceptions described below. 

 

DATA ISSUES

Method and Analytical Blanks

Several analytes were detected in the preparation blanks (PB), initial calibration blanks (ICBs), and 

continuing calibration blanks (CCBs) associated with the samples in this episode at concentrations greater 

than the respective MDLs, but less than the method-specified MLs. The data quality is affected as 

follows: 

• Sample Results Less than Five Times Blank Results: When the sample result is less than five 

times the blank result, there are no means by which to ascertain whether or not the presence of the 

analyte may be attributed to contamination. Therefore, CSC recommends that the data be 

reported in the database as a not detected at the ML, adjusted for sample size, dilution, and 

matrices. The affected samples and analytes are as follows: 70420 dissolved Sb; 70421 dissolved 

and total Sb; 70422 dissolved and total Sb; 70424 dissolved and total Sb. 

• Sample Results Greater than Ten Times Blank Results or Analyte Not Detected in Sample: CSC 

does not consider the presence of the analyte in the blank to adversely affect the data in cases 

where the sample results are greater than ten times the associated blank results or where the 

analyte is not detected in associated samples. Because CSC considers such data to be acceptable 

without qualification, these cases do not merit further detail. 

Field Blanks 

CSC reviewed results from four field blanks. All field blanks exhibited no results above the ML with the 

following exceptions: hexavalent chromium in sample 70426, 70427, and 70428; dissolved copper in 

sample 70428. Per EPA request, CSC does not qualify results based on field blank contamination. 

MS/MSD 

The recovery for total cadmium (116%) in the MS performed on sample 70420 was marginally above 

Method 1638 limits (84 – 113%). CSC recommends that the total cadmium result for the unspiked 

sample 70420 be considered of acceptable quality, but may be a maximum value. 

The RPD for dissolved chromium (21%) for the MS/MSD set performed on sample 70420 was just above 

laboratory limits (20%). Recoveries for both the MS and MSD were acceptable. Because dissolved 

chromium was not detected in the unspiked sample, CSC recommends that the results be included in the 

database without qualification. 

The recovery for dissolved arsenic (74%) in the MSD performed on sample 70420 was slightly below 

laboratory limits (75 – 125%). CSC recommends that the total cadmium result for the unspiked sample 

70420 be considered of acceptable quality, but may be a minimum value. 
4 

TECHNICAL NOTES 

Sample Temperature 

Trace metals samples were not chilled during shipment for this study. 

Additional Analytes 

Two additional analytes, arsenic and chromium, were included for evaluation by Method 1638. Because 

they are not specified in the method, the MLs for these (0.15 μg/L and 0.80 μg/L, respectively) were set 

well above the laboratory-determined MDL. 

Minimum Levels 

In order to alleviate interference caused by high levels of dissolved solids, the laboratory performed 

various dilutions on several samples on which Method 1636 and 1638 were performed. MLs are adjusted 

appropriately. 

Solid-Phase Calculations 

CSC calculated the solid-phase results using the following formula: 

The results for the various phases will be labeled in the PROCEDUR field of the EPA database as 

“DISSOLVED”, “TOTAL”, and “CALCULATED SOLID (DRY WEIGHT)”. 

When two results are mathematically combined to obtain a Calculated Solid result, CSC will report the 

larger of the two MLs associated with each result as the Calculated Solid ML. 

In the generation of the Calculated Solid result, at EPA's request, CSC included Total and Dissolved 

concentrations that were greater than the MDL but less than the ML. However, if any concentration was 

affected by contamination in an associated blank at less than 5 times the associated blank result, it was 

changed to a zero before going through the calculation, per CSC's data review protocols. Negative values 

submitted by the laboratory were not used in the calculations. 

The TSS result for the sample 70420 bottle analyzed for mercury is 10490 mg/L. The TSS result for the 

sample 70420 bottle analyzed for Method 1638 metals is 11635 mg/L. 

If you have any questions regarding the analyses of these samples or the review of these data, please 

contact Barbara Beard by telephone at (703) 461-2154, facsimile at (703) 461-8056, or via email at 

bbeard2@csc.com. 

cc: Brian Damico, EPA Deb Bartram, ERG 

Beverly Randolph, EPA TJ Finseth, ERG 

Marla Smith, EPA Lynn Walters, CSC 

Nelson Andrews, EPA Barbara Beard, CSC 

Brian Englert, EPA 

original sample

Total Dissolved

TSS mg L

Conc ng L Conc ng L

/

( . / . / ) Solid phase concentration (ng/mg or μg/g) − =
5 

Table 2 

Data Review Summary Table

Episode: 6548 Analysis: Trace Metals

Industry: STELEC Study Reviewer: Cris Robinson 

Sample Analyte Action Reason SCC Qual Level

70420 

Dissolved 

70421 

Dissolved 

70421 Total 

70422 

Dissolved 

70422 Total 

70424 

Dissolved 

70424 Total 

Sb Report in database 

as non-detect 

Sample result <5x blank 

result NA 

70420 Total Cd Maximum value MS % recovery above 

contract-specified criteria NA 

70420 

Dissolved As Minimum value MS % recovery below 

contract -specified criteria NA 

70420 

Calculated Solid Cd Maximum value Associated total result is a 

maximum NA 

See Database 

NA = Not applicable
Appendix D 

PICTURES FROM THE SAMPLING EPISODE 
D-1 

Figure D-1. Sampler Working Inside a “Cleanbox” 
D-2 

Figure D-2. Sample Tap Splitter at the Influent to FGD Wastewater Treatment System 
D-3 

Figure D-3. Sampling Set Up at the Influent to FGD Wastewater Treatment System (SP-1) 
D-4 

Figure D-4. Sample Collection Point for the 2nd Stage Clarifier Overflow 
D-5 

Figure D-5. Sampling Set Up for the 2nd Stage Clarifier Overflow (SP-2) 
D-6 

Figure D-6. Sample Collection Point for the Effluent from the FGD Wastewater Treatment 

System 
D-7 

Figure D-7. Sampling Set Up at Effluent from FGD Wastewater Treatment System (SP-3) 
D-8 

Figure D-8. Sampling Set Up at Effluent from the Bottom Ash Pond (SP-4)