Document ID: EPA-HQ-OW-2009-0819-6347
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2015-11-03T05:00Z

--------------------------------------------------------------------------------
MEMORANDUM

TO:	Steam Electric Rulemaking Record

FROM:	Dan-Tam Nguyen

DATE:	September 30, 2015

SUBJECT:	Pollutants of Concern Analysis Methodology for FGD Wastewater, Combustion Residual Leachate, and Gasification Wastewater  

	ERG is providing technical support to the U.S. Environmental Protection Agency's Office of Water, Engineering and Analysis Division (EAD) for development of effluent limitations guidelines and standards (ELGs) for the Steam Electric Power Generating Industry. This memorandum describes EPA's methodology for identifying Pollutants of Concern (POCs) in FGD wastewater, combustion residual leachate, and gasification wastewater.  
Introduction
	As part of the final rulemaking, ERG reviewed characterization data for untreated FGD wastewater (FGD purge), combustion residual leachate, and gasification wastewater to identify which pollutants are present in these wastewaters at a sufficient concentration and frequency to be considered treatable. The pollutants that meet these criteria are identified as POCs.  ERG identified POCs separately for each wastestream. Only pollutants identified as POCs are considered in EPA's subsequent pollutant loadings and removals evaluations.  This memorandum only discusses the POC analyses for FGD wastewater, combustion residual leachate and gasification wastewater; the POC analyses for fly ash and bottom ash transport water are discussed separately in Bottom Ash and Fly Ash Pollutants of Concern (POC) Analysis Methodology Memorandum (DCN SE04745).
POC Analysis Methodology
For the proposed rulemaking, EPA conducted the POC analysis by comparing the untreated wastewater sample concentrations to the baseline values that were developed for the 2000 Centralized Waste Treatment (CWT) Industry Effluent Limitations Guidelines [U.S. EPA, 2000; ERG, 2013]. In response to public comments, EPA conducted the analysis for the final rule by comparing sample concentrations to the sample-specific quantitation limit (QL). In the case of FGD wastewater, combustion residual leachate, and gasification wastewater, EPA only used data that included the associated QLs. The QL is often referred to in ELG support documents as the reporting limit. Use of the QL provides a more accurate representation of POCs in untreated wastewater for the following reasons:
 
 The QL is sample-specific and can vary for a given pollutant between samples. The QL provides a direct comparison to the sample result because it accounts for analytical adjustments made in the determination of the sample result.
 The analytical methods used to determine the sample results and QLs are those used for the Steam Electric rulemaking (i.e., EPA Methods 200.7, 200.8 with collision cell, and 1631E) and are capable of achieving QLs that are lower than the baseline values from CWT for many priority and nonconventional pollutants (e.g., arsenic, cadmium, chromium, selenium, magnesium, manganese). In contrast, for example, the CWT baseline values for metals were developed based on instrument detection limits for EPA Method 1620. 
	EPA used the analytical data from the data sources described in Section 3 to identify POCs in each of the wastestreams. EPA reviewed the sample results to identify POCs, which EPA defined as those pollutants detected at greater than or equal to 10 times the QL in at least 10 percent of all untreated wastewater samples for each wastestream. Using 10 times the QL as a screening threshold ensures the untreated wastewater concentrations are high enough to quantify the degree of pollutant removal resulting from treatment processes, such as chemical or biological treatment for FGD wastewater. 

Data Sources Used in the POC Analysis
	EPA's data collection efforts produced data sets from EPA and/or industry-submitted data sources. This section describes the data sources used in the POC analysis for each of the wastestreams. ERG's data quality review procedures for the data collected and used by EPA are outlined in Development Memorandum for the Steam Electric Analytical Database for the Final Rule (DCN SE05876). The data are included in the Steam Electric Analytical Database for the Final Rule (DCN SE05359).

FGD Wastewater
	EPA evaluated sources of analytical data for untreated FGD wastewater, which are summarized in Table 3-1. These data sources are further described in Development Memorandum for the Steam Electric Analytical Database for the Final Rule (DCN SE05876). Because the POC analysis compares the sample results to the QLs, ERG reviewed and excluded any sample results that did not include sample-specific QLs.   

Table 3-1. Summary of Analytical Data for Untreated FGD Wastewater
                                       
                                  Data Source
                                  Plant Name
                       Total Number of Samples Available
                    Number of Samples without QL (Excluded)
                  Number of Samples Included in POC Analysis
EPA Field Sampling Program
Allen Steam Station
                                       4
                                       0
                                       4

Belews Creek Steam Station
                                       4
                                       0
                                       4

Dickerson Generating Station
                                       4
                                       0
                                       4

Hatfield's Ferry Power Station
                                       4
                                       0
                                       4

Keystone Generation Station
                                       4
                                       0
                                       4

Miami Fort Station
                                       4
                                       0
                                       4

Pleasant Prairie Power Plant
                                       4
                                       0
                                       4

Brindisi Power Plant (Italy)
                                       2
                                       0
                                     0 [a]

Monfalcone Power Station (Italy)
                                       1
                                       0
                                     0 [a]
EPA CWA 308 Monitoring Program
Allen Steam Station
                                       4
                                       0
                                       4

Belews Creek Steam Station
                                       4
                                       0
                                       4

Dickerson Generating Station
                                       3
                                       0
                                       3

Hatfield's Ferry Power Station
                                       4
                                       0
                                       4

Iatan
                                       4
                                       0
                                       4

Keystone Generating Station
                                       4
                                       0
                                       4

Miami Fort Station
                                       4
                                       0
                                       4

Pleasant Prairie Power Plant
                                       4
                                       0
                                       4
EPA Data Request
Miami Fort Station
                                      58
                                       7
                                      51

Keystone Generating Station
                                      122
                                       0
                                      122

Allen Steam Station
                                      127
                                 See note [b]
                                       0

Belews Creek Steam Station
                                      138
                                 See note [b]
                                       0

Cliffside Steam Station
                                      51
                                      51
                                       0

Mountaineer Plant
                                      16
                                       0
                                      16
Steam Electric Public Comments on the Proposed Rulemaking
Pleasant Prairie Power Plant
                                      159
                                       0
                                      159
North Carolina Data Request 
Roxboro Steam Plant
                                      54
                                      54
                                       0
Duke Energy Data Request
Allen Steam Station
                                      64
                                 See note [b]
                                       0

Belews Creek Steam Station
                                      73
                                 See note [b]
                                       0
a  -  EPA samples from Brindisi and Monfalcone were not used in the POC analysis because they are not representative of plants operating within the United States. 
b  -  Only non-detect samples had reported sample QLs. EPA determined that excluding only the detected samples which did not include sample QLs would skew the results of the POC analysis; therefore, EPA excluded the entire analytical data sets for these plants. 
      In summary, EPA's data set used to identify POCs in untreated FGD wastewater included:  
      
 EPA Field Sampling Program. EPA included four samples of untreated FGD wastewater from seven steam electric power plants operating FGD wastewater treatment systems for a total of 28 samples. Sample results include 38 analytes, including priority, conventional, and nonconventional pollutants. 
 EPA CWA 308 Monitoring Program. EPA included data from eight plants that each collected three- to four-day samples of untreated FGD wastewater. The data set included a total of 31 samples with sample results for 37 analytes, including priority, conventional, and nonconventional pollutants. 
 Steam Electric Public Comments on the Proposed Rulemaking. EPA included analytical data for untreated FGD wastewater from one plant that submitted results for a total of 159 samples, including data for the priority pollutants arsenic, mercury, and selenium.
 EPA Data Request. EPA included analytical data for untreated FGD wastewater from three plants for a total of 189 samples, including results for the priority and nonconventional pollutants. 
Combustion Residual Leachate
	As part of industry responses to the Questionnaire for the Steam Electric Power Generating Effluent Guidelines (Steam Electric Survey) (DCN SE05903), EPA received analytical data for 322 samples of combustion residual leachate (from landfill and impoundment leachate management units). Table 3-2 summarizes the plants that provided analytical data for this wastestream. Upon further review of the data, EPA excluded samples that represented retired combustion residual leachate management units (49 samples) because the data are not representative of the wastestream regulated by the final rule. Additionally, EPA excluded several samples where the sample QLs were not available (31 samples). 

	In summary, EPA's data set used to identify POCs in combustion residual leachate included data from 33 steam electric power plants with analytical results for 30 analytes from 246 samples (173 landfill leachate samples and 73 impoundment leachate samples).

Table 3-2. Summary of Analytical Data for Combustion Residual Leachate
		
                                Management Unit
                                  Plant Name
                       Total Number of Samples Available
          Number of Samples from Retired Management Units (Excluded)
                    Number of Samples without QL (Excluded)
                  Number of Samples Included in POC Analysis
Landfill

Gibson Generating Station
                                      12
                                       0
                                      12
                                       0

Albright Power Station
                                      20
                                      12
                                       2
                                       6

W. H. Sammis Plant
                                       4
                                       0
                                       0
                                       4

James River Power Station
                                       4
                                       0
                                       4
                                       0

Yorktown Power Station
                                       4
                                       0
                                       0
                                       4

Rivesville Power Station
                                       4
                                       0
                                       0
                                       4

Interstate Power and Light - Sutherland Generating Station
                                       4
                                       4
                                      NA
                                       0

New Castle Power Plant
                                       4
                                       0
                                       0
                                       4

EME Homer City Generation L.P.
                                       8
                                       0
                                       0
                                       8

Conesville
                                       8
                                       0
                                     3 [a]
                                       8

Danskammer Generating Station
                                       4
                                       0
                                       0
                                       4

Walter C Beckjord Station
                                       8
                                       4
                                       0
                                       4

Cayuga
                                       4
                                       0
                                       4
                                       0

Marshall Steam Station
                                       4
                                       0
                                       0
                                       4

Merom Generating Station
                                       8
                                       4
                                       0
                                       4

AES  -  Somerset
                                       9
                                       9
                                      NA
                                       0

Mountaineer Plant
                                       4
                                       0
                                       0
                                       4

Clover Power Station
                                       4
                                       4
                                      NA
                                       0

Plant Crist
                                      10
                                       0
                                       0
                                      10

General James M. Gavin
                                      12
                                       0
                                       0
                                      12

JH Campbell Power Plant
                                       8
                                       0
                                       0
                                       8

Walter Scott Jr. Energy Center
                                      16
                                       0
                                      1 b
                                      16

Pirkey
                                       4
                                       0
                                       0
                                       4

Harrison Power Station
                                      24
                                       0
                                       0
                                      24

Dunkirk Generating Plant
                                       5
                                       0
                                     1[b]
                                       5

Hatfield's Ferry Power Station
                                       8
                                       0
                                       0
                                       8

John Sevier
                                       4
                                       0
                                       0
                                       4

Belews Creek Steam Station
                                       8
                                       0
                                       0
                                       8

RRI Energy Inc. Portland Generating Station
                                       4
                                       0
                                       0
                                       4

Mount Storm Power Station
                                      12
                                       4
                                       0
                                      12
Surface Impoundment

Surface Impoundment (continued)
Rivesville Power Station
                                       4
                                       0
                                       0
                                       4

Cliffside Steam Station
                                      12
                                       8
                                       0
                                       4

Bruce Mansfield Plant
                                       8
                                       0
                                       0
                                       8

Ghent
                                       4
                                       0
                                       0
                                       4

Walter C Beckjord Station
                                       4
                                       0
                                       0
                                       4

Cayuga
                                       4
                                       0
                                       4
                                       0

General James M. Gavin
                                       4
                                       0
                                       0
                                       4

Philip Sporn
                                      16
                                       0
                                       3
                                      13

Big Sandy
                                       8
                                       0
                                       0
                                       8

Widows Creek
                                       8
                                       0
                                       0
                                       8

Buck Steam Station
                                       4
                                       0
                                       0
                                       4

Shawnee
                                       4
                                       0
                                       0
                                       4

Johnsonville
                                       4
                                       0
                                       0
                                       4

Belews Creek Steam Station
                                       4
                                       0
                                       0
                                       4

RRI Energy Inc. Portland Generating Station
                                       2
                                       0
                                       2
                                       0
Note: Samples from retired units are excluded from the POC analysis.
a  -  All samples contained QLs with the exception of three sample results for one pollutant. EPA excluded these sample results from the POC analysis.
b  -  All samples contained QLs with the exception of one sample result for one pollutant. EPA excluded this sample result from the POC analysis.  

Gasification Wastewater 
	During EPA's field sampling activities, EPA collected 20 gasification wastewater samples for 37 analytes from two plants: Polk Power Station and Wabash River Station. Gasification wastewater from these plants includes the following wastestreams: neutralized weak acid wastestream, vapor compression evaporator influent, compression evaporator influent, RCC(R) evaporator influent, sour water treatment influent, and steam stripper effluent. All 20 samples included sample QLs and were included in the POC analysis for gasification wastewater. 

Results of POC Analyses
	Using the methodology outlined in Section 2, EPA conducted separate POC analyses for each of the wastestreams. 
FGD Wastewater
	Table 4-1 presents the number of samples analyzed for each pollutant in FGD wastewater, the number of sample results that were not detected above the sample QL, and the number and percentage of sample results that were detected at a concentration greater than or equal to ten times the sample-specific QL. EPA identified 31 POCs for FGD wastewater (listed in Table 4-2).
Table 4-1. Pollutants of Concern Analysis for FGD Wastewater
                                Pollutant Group
                                   Pollutant
                               Number of Samples
                             Number of ND Samples
                          Number of Samples >=10xQL
                        Percentage of Samples >=10xQL
                         POC (>=10% Samples >=10xQL)
Conventional

Biochemical Oxygen Demand
                                                                             59
                                                                             33
                                                                              0
                                                                           0   
                                       

Total Suspended Solids
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC
Nonconventional 

Aluminum
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Ammonia as Nitrogen
                                                                             72
                                                                             11
                                                                              9
                                                                          12.5 
                                      POC

Barium
                                                                             59
                                                                              0
                                                                             58
                                                                          98.3 
                                      POC

Boron
                                                                             59
                                                                              0
                                                                             47
                                                                          79.7 
                                      POC

Calcium
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Chemical Oxygen Demand
                                                                             59
                                                                              1
                                                                              0
                                                                           0   
                                       

Chloride
                                                                             59
                                                                              0
                                                                             22
                                                                          37.3 
                                      POC

Cobalt
                                                                             59
                                                                              0
                                                                             16
                                                                          27.1 
                                      POC

Hexavalent Chromium
                                                                             27
                                                                             27
                                                                              0
                                                                           0   
                                       

Iron
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Magnesium
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Manganese
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Molybdenum
                                                                             59
                                                                              7
                                                                              8
                                                                          13.6 
                                      POC

Nitrate/Nitrite as Nitrogen
                                                                             75
                                                                              1
                                                                             74
                                                                          98.7 
                                      POC

Nitrogen, Kjeldahl
                                                                             59
                                                                              2
                                                                              0
                                                                           0   
                                       

Sodium
                                                                             59
                                                                              0
                                                                             33
                                                                          55.9 
                                      POC

Sulfate
                                                                             59
                                                                              0
                                                                              0
                                                                           0   
                                       

Tin
                                                                             59
                                                                             59
                                                                              0
                                                                           0   
                                       

Titanium
                                                                             59
                                                                              0
                                                                             58
                                                                          98.3 
                                      POC

Total Dissolved Solids
                                                                             59
                                                                              0
                                                                             58
                                                                          98.3 
                                      POC

Total Phosphorus
                                                                             59
                                                                             17
                                                                             15
                                                                          25.4 
                                      POC

Vanadium
                                                                             59
                                                                              0
                                                                             52
                                                                          88.1 
                                      POC
Priority 

Antimony
                                                                             59
                                                                              7
                                                                             25
                                                                          42.4 
                                      POC

Arsenic
                                                                            221
                                                                              8
                                                                            119
                                                                          53.8 
                                      POC

Beryllium
                                                                             59
                                                                              4
                                                                             10
                                                                          16.9 
                                      POC

Cadmium
                                                                             59
                                                                              6
                                                                             20
                                                                          33.9 
                                      POC

Chromium
                                                                             59
                                                                              0
                                                                             55
                                                                          93.2 
                                      POC

Copper
                                                                             59
                                                                              0
                                                                             55
                                                                          93.2 
                                      POC

Lead
                                                                             59
                                                                              0
                                                                             54
                                                                          91.5 
                                      POC

Mercury
                                                                            456
                                                                              9
                                                                            271
                                                                          59.4 
                                      POC

Nickel
                                                                             59
                                                                              0
                                                                             59
                                                                           100 
                                      POC

Selenium
                                                                             98
                                                                              0
                                                                             97
                                                                          99.0 
                                      POC

Silver
                                                                             59
                                                                             47
                                                                              1
                                                                          1.69 
                                       

Thallium
                                                                             59
                                                                              9
                                                                              9
                                                                          15.3 
                                      POC

Total Cyanide
                                                                             59
                                                                             14
                                                                             11
                                                                          18.6 
                                      POC

Zinc
                                                                             59
                                                                              0
                                                                             50
                                                                          84.7 
                                      POC

Table 4-2. Pollutants of Concern for FGD Wastewater
                                Pollutant Group
                                   Pollutant
Conventional
                            Total Suspended Solids
Nonconventional 

                                   Aluminum

                              Ammonia as Nitrogen

                                    Barium

                                     Boron

                                    Calcium

                                   Chloride

                                    Cobalt

                                     Iron

                                   Magnesium

                                   Manganese

                                  Molybdenum

                          Nitrate/Nitrite as Nitrogen

                                    Sodium

                                   Titanium

                            Total Dissolved Solids

                               Total Phosphorus

                                   Vanadium
Priority 

                                   Antimony

                                    Arsenic

                                   Beryllium

                                    Cadmium

                                   Chromium

                                    Copper

                                     Lead

                                    Mercury

                                    Nickel

                                   Selenium

                                   Thallium

                                 Total Cyanide

                                     Zinc

Combustion Residual Leachate
	Table 4-3 presents the results of EPA's POC analysis and Table 4-4 lists the 25 POCs EPA identified for combustion residual leachate.

Table 4-3. Pollutants of Concern Analysis for Combustion Residual Leachate
                                Pollutant Group
                                   Pollutant
                               Number of Samples
                             Number of ND Samples
                          Number of Samples >=10xQL
                        Percentage of Samples >=10xQL
                         POC (>=10% Samples >=10xQL)
Conventional 
Total Suspended Solids
                                                                            242
                                                                             75
                                                                             37
                                                                           15.3
                                      POC
Nonconventional 

Aluminum
                                                                            242
                                                                             48
                                                                             90
                                                                           37.2
                                      POC

Barium
                                                                            242
                                                                              2
                                                                            156
                                                                           64.5
                                      POC

Boron
                                                                            242
                                                                              4
                                                                            207
                                                                           85.5
                                      POC

Calcium
                                                                            242
                                                                              1
                                                                            234
                                                                           96.7
                                      POC

Chloride
                                                                            242
                                                                              2
                                                                            182
                                                                           75.2
                                      POC

Cobalt
                                                                            242
                                                                             61
                                                                             76
                                                                           31.4
                                      POC

Iron
                                                                            242
                                                                             35
                                                                            104
                                                                           43.0
                                      POC

Magnesium
                                                                            242
                                                                              5
                                                                            216
                                                                           89.3
                                      POC

Manganese
                                                                            242
                                                                             16
                                                                            182
                                                                           75.2
                                      POC

Molybdenum
                                                                            242
                                                                             16
                                                                            188
                                                                           77.7
                                      POC

Sodium
                                                                            242
                                                                              0
                                                                            216
                                                                           89.3
                                      POC

Sulfate
                                                                            242
                                                                              1
                                                                            203
                                                                           83.9
                                      POC

Tin
                                                                            242
                                                                            173
                                                                              5
                                                                           2.07
                                       

Titanium
                                                                            242
                                                                            118
                                                                             11
                                                                           4.55
                                       

Total Dissolved Solids
                                                                            242
                                                                              1
                                                                            241
                                                                           99.6
                                      POC

Vanadium
                                                                            242
                                                                            100
                                                                             49
                                                                           20.2
                                      POC
Priority 

Antimony
                                                                            242
                                                                             76
                                                                             27
                                                                           11.2
                                      POC

Arsenic
                                                                            242
                                                                             28
                                                                            130
                                                                           53.7
                                      POC

Beryllium
                                                                            242
                                                                            166
                                                                             11
                                                                           4.55
                                       

Cadmium
                                                                            242
                                                                             61
                                                                             63
                                                                           26.0
                                      POC

Chromium
                                                                            241
                                                                            112
                                                                             27
                                                                           11.2
                                      POC

Copper
                                                                            242
                                                                             82
                                                                             29
                                                                           12.0
                                      POC

Lead
                                                                            242
                                                                            126
                                                                             21
                                                                           8.68
                                       

Mercury
                                                                            238
                                                                             37
                                                                             85
                                                                           35.7
                                      POC

Nickel
                                                                            242
                                                                             52
                                                                             80
                                                                           33.1
                                      POC

Selenium
                                                                            242
                                                                             24
                                                                             79
                                                                           32.6
                                      POC

Silver
                                                                            242
                                                                            183
                                                                              1
                                                                          0.413
                                       

Thallium
                                                                            242
                                                                             93
                                                                             26
                                                                           10.7
                                      POC

Zinc
                                                                            242
                                                                             69
                                                                             68
                                                                           28.1
                                      POC

Table 4-4. Pollutants of Concern for Combustion Residual Leachate
                                Pollutant Group
                                   Pollutant
Conventional 
                            Total Suspended Solids
Nonconventional 

                                   Aluminum

                                    Barium

                                     Boron

                                    Calcium

                                   Chloride

                                    Cobalt

                                     Iron

                                   Magnesium

                                   Manganese

                                  Molybdenum

                                    Sodium

                                    Sulfate

                            Total Dissolved Solids

                                   Vanadium
Priority 

                                   Antimony

                                    Arsenic

                                    Cadmium

                                   Chromium

                                    Copper

                                    Mercury

                                    Nickel

                                   Selenium

                                   Thallium

                                     Zinc
       
Gasification Wastewater
	Table 4-5 presents the results of EPA's POC analysis and Table 4-6 lists the 34 POCs EPA identified for gasification wastewater.

Table 4-5. Pollutants of Concern Analysis for Gasification Wastewater
                                Pollutant Group
                                   Pollutant
                               Number of Samples
                             Number of ND Samples
                          Number of Samples >=10xQL
                        Percentage of Samples >=10xQL
                         POC (>=10% Samples >=10xQL)
Conventional 
Biochemical Oxygen Demand
                                                                             20
                                                                              4
                                                                              6
                                                                             30
                                      POC

Total Suspended Solids
                                                                             20
                                                                             12
                                                                              2
                                                                             10
                                      POC
Nonconventional 

Aluminum
                                                                             20
                                                                              4
                                                                             14
                                                                             70
                                      POC

Ammonia as Nitrogen
                                                                             20
                                                                              0
                                                                              9
                                                                             45
                                      POC

Barium
                                                                             20
                                                                              6
                                                                              7
                                                                             35
                                      POC

Boron
                                                                             20
                                                                              0
                                                                              9
                                                                             45
                                      POC

Calcium
                                                                             20
                                                                              3
                                                                              4
                                                                             20
                                      POC

Chemical Oxygen Demand
                                                                             20
                                                                              2
                                                                             11
                                                                             55
                                      POC

Chloride
                                                                             20
                                                                              0
                                                                              8
                                                                             40
                                      POC

Cobalt
                                                                             20
                                                                             18
                                                                              2
                                                                             10
                                      POC

Iron
                                                                             20
                                                                              0
                                                                             11
                                                                             55
                                      POC

Magnesium
                                                                             20
                                                                              4
                                                                              7
                                                                             35
                                      POC

Manganese
                                                                             20
                                                                              0
                                                                             11
                                                                             55
                                      POC

Molybdenum
                                                                             20
                                                                              7
                                                                              5
                                                                             25
                                      POC

Nitrate/Nitrite as Nitrogen
                                                                             20
                                                                             13
                                                                              4
                                                                             20
                                      POC

Nitrogen, Kjeldahl
                                                                             20
                                                                              0
                                                                             14
                                                                             70
                                      POC

Total Phosphorus
                                                                             40
                                                                              0
                                                                              4
                                                                             10
                                      POC

Sodium
                                                                             20
                                                                              0
                                                                              8
                                                                             40
                                      POC

Sulfate
                                                                             20
                                                                              4
                                                                              3
                                                                             15
                                      POC

Tin
                                                                             20
                                                                             18
                                                                              0
                                                                              0
                                       

Titanium
                                                                             20
                                                                             12
                                                                              6
                                                                             30
                                      POC

Total Dissolved Solids
                                                                             20
                                                                              0
                                                                             17
                                                                             85
                                      POC

Vanadium
                                                                             20
                                                                              1
                                                                             18
                                                                             90
                                      POC
Priority 

Antimony
                                                                             20
                                                                             16
                                                                              2
                                                                             10
                                      POC

Arsenic
                                                                             20
                                                                              7
                                                                              6
                                                                             30
                                      POC

Beryllium
                                                                             20
                                                                             16
                                                                              2
                                                                             10
                                      POC

Cadmium
                                                                             20
                                                                             18
                                                                              2
                                                                             10
                                      POC

Chromium
                                                                             20
                                                                             14
                                                                              0
                                                                              0
                                       

Copper
                                                                             20
                                                                             13
                                                                              3
                                                                             15
                                      POC

Total Cyanide
                                                                             20
                                                                              5
                                                                             11
                                                                             55
                                      POC

Lead
                                                                             20
                                                                             12
                                                                              4
                                                                             20
                                      POC

Mercury
                                                                             20
                                                                              4
                                                                              7
                                                                             35
                                      POC

Nickel
                                                                             20
                                                                              0
                                                                              2
                                                                             10
                                      POC

Selenium
                                                                             20
                                                                              0
                                                                             14
                                                                             70
                                      POC

Silver
                                                                             20
                                                                             20
                                                                              0
                                                                              0
                                       

Thallium
                                                                             20
                                                                              8
                                                                              9
                                                                             45
                                      POC

Zinc
                                                                             20
                                                                              3
                                                                              3
                                                                             15
                                      POC

Table 4-6. Pollutants of Concern for Gasification Wastewater
                                Pollutant Group
                                   Pollutant
Conventional 
                           Biochemical Oxygen Demand

                            Total Suspended Solids
Nonconventional 

                                   Aluminum

                              Ammonia as Nitrogen

                                    Barium

                                     Boron

                                    Calcium

                            Chemical Oxygen Demand

                                   Chloride

                                    Cobalt

                                     Iron

                                   Magnesium

                                   Manganese

                                  Molybdenum

                             Nitrate Nitrite as N

                              Nitrogen, Kjeldahl

                               Total Phosphorus

                                    Sodium

                                    Sulfate

                                   Titanium

                            Total Dissolved Solids

                                   Vanadium
Priority 

                                   Antimony

                                    Arsenic

                                   Beryllium

                                    Cadmium

                                    Copper

                                 Total Cyanide

                                     Lead

                                    Mercury

                                    Nickel

                                   Selenium

                                   Thallium

                                     Zinc