INTERNAL DRAFT DELIBERATIVE: DO NOT CITE, QUOTE, or DISTRIBUTE 

MEMORANDUM 

TO: Steam Electric Rulemaking Record 

FROM: Danielle Lewis, ERG 

DATE: September 30, 2015 

SUBJECT: Transportation and Disposal Costs for Plants Operating Storage 

Impoundments for the Treatment of Fly Ash and Bottom Ash Transport 

Water 

 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. 

As part of this technical support, EPA, with support from ERG, estimated plant-specific 

compliance costs associated with installing and operating the various technologies and practices 

that make up the regulatory options considered by EPA to revise the existing ELGs. EPA 

estimated compliance costs several different ways to evaluate the effect of the final ELGs on the 

steam electric industry. EPA considered other rulemakings affecting the steam electric industry 

in its analysis. The three different costing approaches used to estimate compliance costs are 

listed below: 

 Approach 1 - EPA evaluated compliance costs taking into account changes that plants 

may make to implement the coal combustion residuals (CCR) rule (but not the Clean 

Power Plan (CPP)). 

 Approach 2 - EPA evaluated compliance costs taking into account changes that plants 

may make to implement both the CCR rule and the CPP.1

 

 Approach 3 - EPA evaluated compliance costs taking into account no changes from either 

the CCR rule or CPP. This approach represents what the ELG costs would be if there 

were no changes to plant operations due to the CCR rule or CPP (in other words, what the 

ELG compliance costs would be if the CCR rule and CPP had not been promulgated). 

The methodologies used to estimate costs for each of the three approaches are discussed in the 

Incremental Costs and Pollutant Removals for the Final Effluent Limitations Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category (DCN SE05831 and 

SE05832). The report also includes detailed plant-level compliance cost estimates for the three 

different approaches in the appendices of the report (DCN SE05831.A1 and SE05831.A2). 

 

 

1

 At the time it conducted these analyses, the CPP had not yet been finalized, and thus EPA used the proposed CPP 

for its analyses. 
Memorandum 

September 30, 2015 

Page 2 

 As part of the compliance cost estimates, EPA calculates costs associated with 

transporting and disposing of any additional combustion residuals (i.e., fly ash, bottom ash, and 

FGD wastewater treatment solids) resulting from compliance with the ELGs.2 EPA’s 

methodology includes costs for each plant to transport and dispose of these additional 

combustion residuals in either an on-site or off-site landfill based on whether or not the plant 

currently operates a landfill containing combustion residuals.3

 Under EPA’s Approach 3 for 

estimating compliance costs (i.e., costs not accounting for the CCR rule and CPP), transportation 

and disposal costs were included for all plants based on the total amount of incremental waste 

(e.g., treatment solids, ash converted from wet to dry handling) generated at each plant.4 Upon 

reviewing comments on the proposed rule regarding EPA’s cost methodology for compliance 

with a zero discharge requirement for ash transport water, EPA determined that it is not 

necessary (nor appropriate) to include transportation and disposal costs for those plants that send 

fly ash or bottom ash to a storage impoundment5, and that do not report disposing of fly ash or 

bottom ash in an impoundment. Because these plants use their impoundments only for temporary 

storage of the ash, and thus are already regularly dredging and hauling the solids to other final 

disposal (e.g., a landfill, beneficial use), there should be no transport or disposal cost attributed to 

the ELG even if the ELG requirements lead the plant to convert to a dry ash system. 

Nevertheless, these transport and disposal costs were retained in the cost estimates for Approach 

3 as an upper bound of the potential cost to comply with the ELGs. 

 EPA’s methodology for estimating transportation and disposal costs for Approach 1 and 

Approach 2 take into account that plants using storage impoundments are already periodically 

hauling the solids to a landfill (or beneficial use). For these approaches, EPA reviewed the U.S. 

Energy Information Administration (EIA) data that EPA used for the CCR rule to identify the 

plants operating only storage impoundments under the CCR rule. For these plants, EPA 

evaluated whether fly ash and/or bottom ash were reported as “disposed” in the EIA data. Where 

plants reported to EIA that they are disposing of those CCR materials in places other than the 

impoundments (e.g., landfill, beneficial reuse), EPA determined that there would be no 

incremental change to the transportation and disposal costs for these plants after conversion to 

dry handling operations. For example, if a plant’s current operation consists of wet sluicing fly 

ash to an impoundment, dredging the solids on an annual basis, and disposing of the solids in an 

off-site landfill, EPA assumed that there would be no increase in the costs for that 

 

2

 Although compliance with the ELGs may result in generating solids associated with the wastewater treatment 

processes, such as from the chemical precipitation stage of the FGD wastewater treatment system, the ELGs would 

not result in generating additional fly ash or bottom ash solids. Compliance with the ELGs, however, could result in 

plants disposing of fly ash or bottom in a landfill instead of an impoundment (e.g., due to wet-to-dry conversion of 

the ash handling system), and EPA’s ELG analyses included costs for such transport and landfill disposal, where 

appropriate. 

3

 As described in the Incremental Costs and Pollutant Removals for the Final Effluent Limitations Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category (DCN SE05904), plants with existing 

on-site landfills already containing combustion residuals were costed to transport and dispose of additional solids in 

an on-site landfill while all other plants were costed to transport and dispose of additional solids in an off-site 

landfill. 

4

 EPA determined that some plants incurring fly ash compliance costs did not have any incremental fly ash 

generated at the plant as a result of the ELG. These plants incurred capital costs associated with backup or redundant 

equipment only or only incurred compliance costs associated with expanding the capacity of specific system 

elements (e.g., conveyance, silo) based on information provided in the Steam Electric Survey. 5

 A storage impoundment is generally defined as an impoundment that is periodically dredged and has its CCR 

disposed elsewhere such that it can continue operating indefinitely. 
Memorandum 

September 30, 2015 

Page 3 

transportation/disposal compared to trucking the dry fly ash to the same off-site landfill after the 

plant converts to a dry fly ash handling system to comply with the final ELG.6 As such, EPA 

included no incremental costs for transportation or disposal attributable to the ELG for these 

plants. 

 As noted above, by unnecessarily including transportation/disposal costs for plants that 

do not dispose of ash in an impoundment, Approach 3 provides an upper bound estimate of 

potential costs for the ELG, especially because this approach does not take into account the 

effects of implementing the CCR rule and CPP. EPA also evaluated how the total industry costs 

under Approach 3 would be affected if the transportation and disposal costs for those plants 

operating only storage impoundments were removed (zeroed out). Based on a review of the EIA 

data, EPA identified 10 plants operating fly ash storage impoundments and 72 plants operating 

bottom ash storage impoundments affected by this methodology change. Table 1 summarizes the 

changes to total industry fly ash conversion costs and bottom ash conversion costs by removing 

all transportation and disposal costs for these plants. 

Table 1. Approximate Change in Compliance Cost Estimates Under Approach 3 for Fly 

Ash Transport Water and Bottom Ash Transport Water Without CCR and CPP 

Adjusting for Transport and Disposal Costs 

Wastestream Number of 

Plants Affected 

Approximate Change in Cost 

(Estimated Reduction in Costs) 

Capital Costs O&M Costs 

Fly Ash Transport Water 10 4.60% 22.7% 

Bottom Ash Transport Water 72 1.88% 26.3% 

TOTAL 74a 2.13% 25.5% 

Note: Percent change shown represents how costs estimated using Approach 3 (i.e., not taking into account the CCR 

rule or CPP) without transportation and disposal costs for storage impoundments compare to the costs estimated 

using Approach 3 with transportation and disposal costs for storage impoundments. 

a – The number of plants is not additive as one plant may operate both a fly ash storage impoundment and a bottom 

ash storage impoundment. 

 

6

 In fact, these plants would be more likely to realize a cost savings since they would no longer have to dredge the 

ash from surface impoundments.