September 25, 2015 Abt Associates | Wastestream Control Technologies Cost-Effectiveness | pg 1

Date September 25, 2015 

To Steam Electric ELGs Record 

From Isabelle Morin 

Subject Compliance Costs, Loading Reductions, and Cost-Effectiveness by Wastestream Control 

Technologies 

1 Introduction 

This memorandum presents the estimated compliance costs, pollutant loadings, and cost-effectiveness of 

each wastestream and technology option analyzed as components of the regulatory options. The data 

supplement information presented in Appendix F of the Regulatory Impact Analysis (RIA) document for 

the final rule (U.S. EPA, 2015a). All results are based on the scenario that accounts for the impacts of the 

Clean Power Plan rule. Refer to the RIA document for details on methodologies for estimating 

compliance costs and cost-effectiveness. Refer to the Technical Development Document (TDD) for the 

final rule for details on loading estimates (U.S. EPA, 2015b). 

2 Results 

2.1 Compliance Costs 

Table 2-1 presents estimated annualized costs for each wastestream and technology option analyzed by 

EPA. 

Table 2-1: Total Annualized Pre-Tax Compliance Costs (in millions, $2013, at 2015) 

Wastestream Technology Option 

Number of Plants 

with Costs 

Total Costs 

(million 2013$) 

Incremental 

Costsa 

(million 2013$) 

FGD Chemical Precipitation 69 $112.5 $112.5

Chemical Precipitation + Biological 69 $194.8 $82.3

Chemical Precipitation + Evaporation 69 $994.6 $799.7

Fly Ash Dry Handling 16 $9.4 $9.4

Bottom Ash Dry Handling for Units > 400 MW 103 $195.9 $195.9

Dry Handling for Units > 50 MW 61 $292.0 $96.1

Landfill Leachate Chemical Precipitation 60 $57.7 $57.7

Source: U.S. EPA Analysis, 2015. 

a Incremental costs calculated relative to the next less stringent technology option for the wastestream.

2.2 Loading Reductions 

Table 2-2 presents estimated pollutant removals for each wastestream and technology option analyzed by 

EPA on both a total pounds basis and toxic-weighted pound equivalent (TWPE) basis. 

Memorandum 

Environment and Resources 
September 25, 2015 Abt Associates | Wastestream Control Technologies Cost-Effectiveness | pg 2

Table 2-2: Total Annual Pollutant Removals 

Wastestream Technology Option 

Pollutant Removals 

(TWPE/year) 

Incremental Pollutant 

Removals (TWPE/Year) 

FGD Chemical Precipitation 706,133 706,133 

Chemical Precipitation + Biological 825,753 119,620 

Chemical Precipitation + Evaporation Not estimated Not estimated 

Fly Ash Dry Handling 185,090 185,090 

Bottom Ash Dry Handling for Units > 400 MW 251,051 251,051 

Dry Handling for Units > 50 MW 344,014 92,964 

Landfill Leachate Chemical Precipitation 29,574 29,574 

Source: U.S. EPA Analysis, 2015.

2.3 Cost-Effectiveness 

Table 2-3 presents estimated cost-effectiveness by wastestream and technology option analyzed by EPA. 

Incremental cost effectiveness is calculated relative to the next least stringent technology option (or the 

baseline in the case of the least stringent technology option). 

Table 2-3: Total Annual Pollutant Removals 

Wastestream Technology Option 

Total Costs

(million 1981$)a Cost 

Effectiveness 

(1981$/TWPE) 

Incremental Cost 

Effectiveness 

(1981$/TWPE) 

FGD Chemical Precipitation $41.7 $59.0 $59.0 

Chemical Precipitation + Biological $72.1 $87.4 $254.7 

Chemical Precipitation + Evaporation $368.3 Not calculatedb Not calculatedb

Fly Ash Dry Handling $3.5 $18.7 $18.7 

Bottom Ash Dry Handling for Units > 400 MW $72.5 $288.9 $288.9 

Dry Handling for Units > 50 MW $108.1 $314.3 $382.8 

Landfill Leachate Chemical Precipitation $21.4 $722.8 $722.8 

Source: U.S. EPA Analysis, 2015. a

 Costs restated in 1981 dollars based on the Construction Cost Index (CCI1981/CCI2013 = 0.370) 

b Pollutant removals for chemical precipitation + evaporation technology is not available and therefore cost effectiveness was not 

calculated.

3 Sensitivity Analysis on Treatment of Non-Detects 

For the purposes of calculating pollutant loadings under this action, EPA handled non-detect values in the 

reported data by replacing them with a value equal to one-half of the detection level for the measurement 

method that yielded the non-detect. This methodology is standard procedure for the ELG program as well 

as other CWA applications, and has been consistently followed in previous ELGs. 

The detection methods used to sample ash transport water vary in sensitivity between samples and across 

plants, and also vary accordingly in their non-detect levels across pollutants. In response to the proposed 

rule, commenters raised concerns that for some pollutants the loadings calculations (particularly for 

bottom ash, but also for fly ash) were biased high as a result of high non-detected values in the reported 

data, and that assigning one half of the detection level to these results could overstate the average 

pollutant loadings. 

To assess this concern, EPA explored an alternative method for treating non-detects. The alternative 

method provides an upper bound on the effect of non-detects on the pollutant loadings. Details of the 

revisions are provided in the TDD for the final rule. The impact of this alternative calculation on costeffectiveness on a technology-specific basis is summarized below. 
September 25, 2015 Abt Associates | Wastestream Control Technologies Cost-Effectiveness | pg 3

The results show that the alternative treatment of non-detects increases cost effectiveness ratios for dry 

handling slightly for fly ash ($19/TWPE to $20/TWPE) and more markedly for bottom ash ($314/TWPE 

to $456/TWPE; based on a 50 MW threshold). Ratios for the FGD and landfill leachate wastestreams are 

unaffected. See Table 3-2 below for details. 

3.1 Compliance Costs 

Compliance costs for the technology options are not affected by the treatment of non-detects and the 

relevant costs are therefore the same as reported in Table 2-1 above. 

3.2 Loading Reductions 

Table 2-2 presents estimated pollutant removals for each wastestream and technology option when 

revising loadings using an alternative treatment of non-detects. 

Table 3-1: Total Annual Pollutant Removals 

Wastestream Technology Option 

Pollutant Removals 

(TWPE/year) 

Incremental Pollutant 

Removals (TWPE/Year) 

FGD Chemical Precipitation 706,133 706,133 

Chemical Precipitation + Biological 825,753 119,620 

Chemical Precipitation + Evaporation Not estimated Not estimated 

Fly Ash Dry Handling 171,398 171,398 

Bottom Ash Dry Handling for Units > 400 MW 172,835 172,835 

Dry Handling for Units > 50 MW 236,402 63,567 

Landfill Leachate Chemical Precipitation 29,574 29,574 

Source: U.S. EPA Analysis, 2015.

3.3 Cost-Effectiveness 

Table 2-2 presents estimated cost-effectiveness by wastestream and technology option analyzed by EPA 

for the sensitivity analysis. 

Table 3-2: Total Annual Pollutant Removals 

Wastestream Technology Option 

Total Costs

(million 1981$)a Cost 

Effectiveness 

(1981$/TWPE) 

Incremental Cost 

Effectiveness 

(1981$/TWPE) 

FGD Chemical Precipitation $41.7 $59.0 $59.0

Chemical Precipitation + Biological $72.1 $87.4 $254.7

Chemical Precipitation + Evaporation $368.3 Not calculatedb Not calculatedb

Fly Ash Dry Handling $3.5 $20.2 $20.2

Bottom Ash Dry Handling for Units > 400 MW $72.5 $419.6 $419.6

Dry Handling for Units > 50 MW $108.1 $457.3 $559.8

Landfill Leachate Chemical Precipitation $21.4 $722.8 $722.8

Source: U.S. EPA Analysis, 2015. a

 Costs restated in 1981 dollars based on the Construction Cost Index (CCI1981/CCI2013 = 0.370) 

b Pollutant removals for chemical precipitation + evaporation technology is not available and therefore cost effectiveness was not 

calculated.

4 References 

U.S. Environmental Protection Agency (U.S. EPA). 2015a. Regulatory Impact Analysis for the Effluent 

Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category 

(RIA) (DCN SE05976). 
September 25, 2015 Abt Associates | Wastestream Control Technologies Cost-Effectiveness | pg 4

U.S. Environmental Protection Agency (U.S. EPA). 2015b. Technical Development Document for the 

Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source 

Category (TDD) (DCN SE05904).