Date: September 7, 2010 

Subject: Emissions Reductions and Cost Effectiveness of Composite Mesh Pads for 

Chromium Electroplating 

Emission Standards Technical Support and Post Promulgation Activities 

EPA Contract No. EP-D-06-118; EPA Work Assignment No. 4-6 

RTI Project No. 0210426.004.006 

From: Cindy Hancy 

 Richard Marinshaw 

To: Phil Mulrine, EPA/OAQPS/SPPD/MMG 

The purpose of this memorandum is to present the estimated emissions reductions, costs, 

and cost effectiveness of retrofitting composite mesh pads (CMP) on existing sources subject to 

the National Emission Standards for Chromium Emissions from Hard and Decorative Chromium 

Electroplating and Chromium Anodizing Tanks (Chromium Electroplating NESHAP, 40 CFR 

63, subpart N). Retrofitting CMPs is being considered as one regulatory option for reducing the 

risk associated with chromium emissions from chromium electroplating and anodizing. 

Section I of this memorandum discusses the estimated number of plants that would be 

affected by the CMP retrofit option. Baseline emissions and emissions reductions associated 

with retrofitting CMPs on existing affected sources are presented in Section II. Section III 

describes the basis for, and results of, the cost estimates for retrofitting CMP's on the affected 

sources. The nationwide cost-effectiveness attributed to the CMP retrofit option is summarized 

in Section IV. References are provided in Section V. 

I. Number of Affected Sources

 The option of retrofitting CMPs on existing sources would affect all hard chromium 

electroplating, decorative chromium electroplating, and chromium anodizing tanks that are not 

currently equipped with CMP's. Specifically, this option would apply to the following: 

1. Sources that use wetting agent fume suppressants (WAFS) as the only means of emission 

control; 

2. Source equipped with add-on control devices, such as packed bed scrubbers (PBS) or 

mesh pad mist eliminators (MPME), that are not as effective as CMPs in controlling 

chromium compound emissions; and 

3. For hard chromium electroplating, only those sources at facilities that are classified as 

small under Section §63.341 of the NESHAP. 

 
2 

 To estimate the number of affected sources by type and size, the distribution of plants by 

size was applied to the number of each type of plant. Table 1 summarizes the estimated number 

of chromium electroplating and anodizing plants nationwide. 

Table 1. Estimated Number of Chromium Electroplating Plantsa

Process 

Estimated No. 

of plants 

Hard chromium electroplating 790 

Decorative chromium electroplating 740 

Chromium anodizing 240 

Total 1,770 a Reference 1. 

 The numbers of chromium electroplating and anodizing plants by size were estimated 

using the model plants and plant distributions developed for the NESHAP and documented in 

Chromium Emissions from Chromium Electroplating and Chromic Acid Anodizing Operations -- 

Background Information for Proposed Standards (Reference 2). Three sizes of model plants 

(small, medium, and large) were developed for hard and decorative chromium electroplating, and 

two sizes of model plants (small and large) were developed for chromium anodizing. Table 2 

summarizes the resulting nationwide breakdown of plants by type and size when the percentages 

of each type of plant are applied to the number of plants shown in Table 1. 

Table 2. Distribution of Model Plants by Size and Type 

Electroplating Type Size % of totala

No. of plants 

nationwide 

Hard Chromium 

Small 70% 553 

Medium 20% 158 

Large 10% 79 

Total 790 

Decorative Chromium 

Small 80% 592 

Medium 15% 111 

Large 5% 37 

Total 740 

Chromium Anodizing 

Small 75% 180 

Large 25% 60 

Total 240 

 Total, all plants 1,770 a

 Reference 2. 

 The distribution of emission control methods among the various types of chromium 

electroplating plants and plant sizes was estimated based on general knowledge of the industry. 

Large hard chromium electroplating plants generally are controlled with CMPs; some PBSs are 
3 

also used. For medium and small hard chromium electroplating plants, PBSs are more common. 

Some medium and small hard chromium electroplating plants also use WAFS to control 

emissions. Wetting agent fume suppressants are the most commonly used control method for 

decorative chromium electroplating and chromium anodizing plants. However, other controls 

(PBS, MPME) also are used. To estimate the distribution, the percentage of plants that use 

WAFS was first assumed; then the percentages of each type of add-on control devices were 

estimated. For example, for small hard chromium electroplating, it was assumed that 20 percent 

are controlled with WAFS. For the remaining 80 percent, it was assumed that 20 percent are 

controlled with CMP. Therefore, the overall percentage controlled with CMP is: 

80% × 20% = 16%. 

Since the control efficiencies for PBS and MPME are comparable, no distinctions were made 

between the two with respect to their distribution. Table 3 summarizes the assumed distribution 

of these controls among the various types of model plants. The resulting numbers of plants are 

summarized in Table 4. For the distribution shown in Table 4, the number of plants that would 

be affected by the CMP retrofit option would be those that are controlled with WAFS, PBS, or 

MPME. 

Table 3. Distribution of Emission Controls among Model Plants 

Electroplating Type 

Model 

Plant Size 

% of Total 

CMP PBS/MPME WAFS 

Hard Chromium 

Small 16 64 20 

Medium 54 36 10 

Large 90 10 0 

Decorative Chromium 

Small 0 10 90 

Medium 2 18 80 

Large 8 32 60 

Chromium Anodizing Small 0 10 90 

Large 8 32 60 

Table 4. Estimated Number of Model Plants for each Emission Control Method 

Electroplating Type 

Model 

Plant Size 

Number of Plants Nationwide 

CMP PBS/MPME WAFS Total 

Hard Chromium 

Small 88 354 111 553 

Medium 85 57 16 158 

Large 71 8 0 79 

Total 790 

Decorative Chromium 

Small 0 59 533 592 

Medium 2 20 89 111 

Large 3 12 22 37 

Total 740 

Chromium Anodizing Small 0 18 162 180 

Large 5 19 36 60 
4 

Total 240 

 

 As noted previously, for hard chromium electroplating, it is assumed the CMP retrofit 

option would apply only to facilities classified as "small hard chromium electroplating facilities" 

under the NESHAP. Section 63.341 of the NESHAP defines "small hard chromium 

electroplating facility" as a facility with a maximum cumulative potential rectifier capacity less 

than 60 million ampere hours per year (A-hr/yr). The NESHAP defines the term "large hard 

chromium electroplating facility" as a facility that has a maximum cumulative potential rectifier 

capacity greater than or equal to 60 million A-hr/yr. The reason for the assumption that the CMP 

retrofit option would not apply to large hard chromium facilities is that any such facility would 

need a control system at least as effective as a CMP to meet the more stringent emission limits 

for large hard chromium electroplating facilities. 

 It should be noted that are is a distinction between the hard chromium electroplating 

facility size criteria specified in the NESHAP and the model plant sizes. Table 5 shows a 

comparison of these criteria. 

Table 5. Size Criteria for Hard Chromium Electroplating 

Model Plant Criteriaa NESHAP Criteriab

Plant Size 

Cumulative rectifier 

capacity, Amp-hr/yr Plant Size 

Cumulative rectifier 

capacity, A-hr/yr 

Small 5 million Small < 60 million 

Medium 42 million NA NA 

Large 160 million Large ≥ 60 million a Reference 2. 

 b §63.341. NA = not applicable. 

 It is clear from a comparison that a small model plant would be classified as a small hard 

chromium electroplating facility under the NESHAP, and a large hard chromium electroplating 

model plant would be classified as a large hard chromium electroplating facility under the 

NESHAP. However, the population of plants represented by the medium hard chromium model 

plant would be divided among the NESHAP categories for small and large facilities. For the 

purposes of estimating the number of sources and impacts associated with medium size model 

plants, it was assumed that 33 percent of the facilities that are represented by the medium size 

model plants are classified as large hard chromium electroplating facilities under the NESHAP, 

and the remaining 67 percent of facilities are classified as small hard chromium electroplating 

facilities under the NESHAP. Table 6 shows the final breakdown of plants that would be 

affected by the CMP retrofit option after removing the medium size hard chromium model plants 

that would be classified as large under the NESHAP. As shown in the table, of the 73 medium 

size hard chromium plants nationwide, 24 plants would be classified as large hard chromium 

electroplating facilities, and 49 plants would be classified as small hard chromium electroplating 

facilities when these assumptions are used. 
5 

Table 6. Summary of Plants Potentially Affected by CMP Retrofit Option 

Electroplating Type 

Model 

Plant Size 

No. of Plants Nationwide

Total 

Classified as 

Large under 

§63.341

No. of 

Affected 

Plants 

PBS/MPME WAFS 

Hard Chromium 

Small 354 111 465 0 465 

Medium 57 16 73 24 49 

Large 8 0 8 8 0 

Total 514 

Decorative Chromium 

Small 59 533 592 NA 592 

Medium 20 89 109 NA 109 

Large 12 22 34 NA 34 

Total 735 

Chromium Anodizing 

Small 18 162 180 NA 180 

Large 19 36 55 NA 55 

Total 235 

 

II. Baseline Emissions

 The basic methodology used to estimate baseline emissions from chromium 

electroplating and anodizing sources was to apply control efficiencies to the uncontrolled 

emissions developed for the original NESHAP for each size model plant and sum up the 

nationwide totals. Table 7 summarizes the uncontrolled emissions for the model plants 

developed for the NESHAP. 

Table 7. Uncontrolled Chromium Compound Emissions from Model Plantsa

Electroplating Type Size 

Uncontrolled Cr 

emissions, lbs/yr 

Hard Chromium Small 110 

Medium 926 

Decorative Chromium 

Small 13 

Medium 53 

Large 530 

Chromium Anodizing Small 7.2 

Large 88 a

 Reference 2. 

 

 Table 8 summarizes the control efficiencies applied to the uncontrolled chromium 

electroplating model plant emissions listed in Table 7. With the exception of CMP, these are 

based on the control efficiencies used to estimate the impacts of the NESHAP. For CMP, a 

control efficiency of 99.5 percent was used for estimating impacts. However, for the estimate 

presented in this memorandum, a control efficiency of 99.9 percent is used. The higher control 

efficiency was assumed because the CMP costs are based on a 4-stage CMP, which should 

achieve a higher level of control than the 3-stage CMP design that was used for estimating the 

impacts of the NESHAP. 
6 

Table 8. Efficiencies of Chromium Electroplating Emission Controlsa

Control Method Efficiency, % 

Composite mesh pad (CMP) 99.9 

Packed bed scrubber (PBS) 99.0 

Mesh pad mist eliminator (MPME) 99.0 

Wetting agent fume suppressant (WAFS) 99.5 a Reference 2, except for CMP. 

 Using the data and distributions discussed above and summarized in Tables 1 through 8, 

nationwide baseline emissions of chromium compounds were estimated for the facilities that 

would be affected by the CMP retrofit option. These emissions are summarized by 

electroplating plant type in Table 9. Nationwide baseline emissions for these facilities are 

estimated to be 1,088 pounds per year (lbs/yr) (0.54 tons per year [tons/yr]). This total is 

comprised of 850 lbs/yr for hard chromium electroplating, 198 lbs/yr for decorative chromium 

electroplating, and 40 lbs/yr for chromium anodizing. 

Table 9. Estimated Nationwide Baseline Emissions for CMP Retrofit Option 

Electroplating Type Model Plant Size 

Nationwide 

Emissions, lbs/yr 

Hard Chromium 

Small 450 

Medium 401 

Total 850 

Decorative Chromium 

Small 42.3 

Medium 34.2 

Large 121 

Total 198 

Chromium Anodizing 

Small 7.1 

Large 32.7 

Total 39.9 

Nationwide total 1,088 

 

III. CMP Retrofit Costs

 

 This section describes the methodology, data, and assumptions used to estimate the costs 

of retrofitting CMPs on existing sources subject to the Chromium Electroplating NESHAP. In 

estimating costs, distinctions were made between sources controlled with existing non-CMP addon controls, and sources that use WAFS and are not equipped with add-on controls. For systems 

with existing add-on controls, a retrofit factor of 50 percent of the CMP system cost was 

incorporated into CMP installation costs. For systems without existing add-on controls, a retrofit 

factor was not applied to the costs. However, for those systems, it was necessary to include costs 

associated with the installation of an exhaust and ventilation system. As noted previously, for 

hard chromium facilities, it was assumed that large facilities are already equipped with CMPs, 

and only small facilities (less than 60 million A-hr/yr) would incur costs associated with 

retrofitting CMPs. 
7 

Sources with Existing Add-On Controls 

 Cost quotes for 3-stage and 4-stage CMP systems were obtained for two different exhaust 

flow rates: 12,000 and 35,000 actual cubic feet per minute (acfm). The quotes did not include 

the costs associated with ventilation systems (i.e., hoods, duct work, etc.). Because the quotes 

were for budgetary purposes, detailed itemization was not provided. For the cost components 

not provided by the CMP vendor, assumptions were based on quotes provided for HEPA filters 

or the EPA Air Pollution Control Cost Manual.

3

 Presented in Table 10 are the capital and initial 

costs components and the basis for those costs. 

Table 10. Cost Components and Assumptions Used to Estimate CMP Retrofit Costs 

Cost Component Assumption 

System Included in quote 

Instrumentation Not included; assumed 11% of equipment costa

Sales tax Assumed 6% 

Freight Assumed $2,000b

Installation Assumed plus $16,000b

Performance testing Assumed 0.7% of installation costa

Contingencies Assumed 2.1% of installation costa

Retrofit Cost Assumed 50% of capital costa

(Only for facilities with existing add-on control device; 

included in overall installation cost) a

 Reference 3. 

b

 Reference 4. 

 Table 11 presents the annual cost components considered in the estimate, the assumptions 

used, and the information source. 

Table 11. Annual Cost Components and Assumptions Used for CMP Retrofit Costs 

Cost Component Source/Method 

Labor hours NESHAP BIDa 

Labor rates Department of Laborb

Mesh Pad Replacement Original NESHAP scaled to 2009 dollarsc

Electricity $0.14/kwhrd

Property Tax & Insurance 4% of capital coste

a

 Reference 2. 

 b Reference 5. 

c

 Reference 6. 

d

 Reference 7. 

e

 Reference 3. 

 For the purpose of this cost analysis, the quotes for the 4-stage CMP system at design 

exhaust rates of 12,000 and 35,000 acfm were used. The capital costs for each design were 
8 

annualized using an interest rate of 7 percent and 15-year lifetime. Annualized capital costs were 

added to the estimated annual costs presented in Table 11, and a cost curve was determined by 

plotting exhaust flow (independent variable) versus total annualized cost (dependent variable). 

The equation of the best-fit line was then used to determine the total annualized cost for the 

model facilities for hard chromium, decorative plating, and anodizing facilities. Presented in 

Figure 1 is the annualized cost curve for retrofitting a new CMP system on a chromium 

electroplating source with existing non-CMP add-on controls. 

Figure 1. Annualized Cost Curve for Retrofitting CMPs on Existing Chromium 

Electroplating Source with Existing Add-on Controls. 

y = 1.288x + 9885.9

$0

$10,000

$20,000

$30,000

$40,000

$50,000

$60,000

‐ 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000

 The cost curve was used to estimate the cost per model plant, which was then multiplied 

by the number of plants nationwide. Based on this methodology, the estimated annualized cost 

to retrofit a new CMP on all sources with existing add-on controls is $16.3 million. This cost is 

comprised of $11.0 million for hard chromium electroplating plants, $3.6 million for decorative 

chromium electroplating plants, and $1.6 million for chromium anodizing plants. Table 12 shows 

the detailed cost and number of facilities for each type of model plant. 

Table 12. Nationwide Annualized Costs for CMP Retrofit - Sources with Existing non-CMP 

Add-on Controls 

Electroplating Type Number of 

Facilities 

Nationwide 

Annualized Cost, $/yr 

Hard chromium electroplating 392 $11,049,600 

Decorative chromium electroplating 91 $3,565,500 

Chromium anodizing 37 $1,635,100 

Total 520 $16,250,300 
9 

Sources without Existing Add-On Controls

 For existing chromium electroplating and anodizing sources that are controlled with 

WAFS and are not equipped with existing add-on controls, the same basic methodology was 

used as described in the previous paragraphs. However, the 50 percent retrofit factor was 

excluded from the calculations, and the costs for installing an exhaust system and ductwork were 

included. Presented in Figure 2 is the annualized cost curve for retrofitting a new CMP system 

on a chromium electroplating source without existing add-on controls. 

 

Figure 2. Annualized Cost Curve for Retrofitting CMPs on Existing Chromium 

Electroplating Source without Existing Add-on Controls. 

y = 1.0645x + 9658.4

$0

$10,000

$20,000

$30,000

$40,000

$50,000

‐ 10,000 20,000 30,000 40,000

The cost curve shown in Figure 2 was used to estimate the cost per model plant, which was then 

multiplied by the number of plants nationwide. The resulting annualized cost to retrofit a new 

CMP system on all sources subject to the NESHAP without existing add-on controls was 

estimated to be $29.9 million. Table 13 shows a breakdown of the annualized costs for these 

sources. 

Table 13. Nationwide Annualized Costs for CMP Retrofit - Sources without Add-on Controls 

Electroplating Type Number of 

Facilities 

Nationwide 

Annualized Cost, $/yr 

Hard chromium electroplating 122 $3,377,500 

Decorative chromium electroplating 644 $19,875,700 

Chromium anodizing 198 $6,623,700 

Total 963 $29,876,900 

 As noted previously, the sources that are not equipped with add-on controls are currently 

controlled using WAFS. After these sources are equipped with CMPs, it is assumed that WAFS 

would no longer be used for emission control. Thus, the costs these facilities currently incur for 
10 

WAFS can be considered a savings after CMP retrofit. Table 14 summarizes the estimated 

annual WAFS cost per model plant. These costs are based on a unit WAFS cost of $186 per 

gallon, an initial WAFS addition (dose) of 0.0025 gallons of WAFS per gallon of electroplating 

tank solution, and maintenance additions of 0.0075 milliliters of WAFS per ampere-hour. 

Reference 8 provides the basis for these costs. 

Table 14. WAFS Cost Savings Following CMP Retrofit 

Electroplating 

Plant Type, Size 

Annual 

Production rate 

per facility, Amphrs/yra

Tank capacity 

per facility, 

gala

Initial Addition 

WAFS Cost per 

facility, $b

Maintenance 

Cost per 

facility, $/yrb

Annual 

Facility 

WAFS Cost, 

$/yr 

Hard Chromium Electroplating 

Small 5,000,000 1,730 $805 $1,843 $2,647 

Medium 42,000,000 8,170 $3,800 $15,478 $19,278 

Decorative Chromium Electroplating 

Small 3,000,000 1,730 $805 $1,106 $1,910 

Medium 12,000,000 3,460 $1,609 $4,422 $6,032 

Large 120,000,000 22,890 $10,647 $44,222 $54,869 

Chromium Anodizing 

Small N/A 1,730 $805 $2,144 $2,949 

Large N/A 19,070 $8,870 $5,528 $14,398 a

 Reference 2. 

b

 See reference 8 for basis of these costs. 

 Using the annual WAFS costs summarized in Table 14, the net costs for retrofitting 

CMPs on tanks that are not equipped with add-on controls was determined. Table 15 

summarizes these costs. The total annualized costs for these sources are $29.9 million/yr, total 

WAFS savings are estimated to be $4.26 million/yr, and the net annualized CMP retrofit costs 

for sources without add-on controls is estimated to be $25.6 million/yr 

Table 15. Nationwide Annualized Costs for CMP Retrofit - Sources without Add-on Controls 

Electroplating Type CMP Retrofit 

Cost, $/yr 

WAFS 

Savings, $/yr 

Net Nationwide 

Annualized Cost, $/yr 

Hard chromium electroplating $3,377,489 $505,902 $2,871,600 

Decorative chromium electroplating $19,875,671 $2,762,073 $17,113,600 

Chromium anodizing $6,623,731 $996,019 $5,627,700 

Total $29,876,900 $4,264,000 $25,612,900 

 Table 16 shows the combined annualized costs for existing sources with add-on controls 

and for sources without add-on controls. Total nationwide annualized costs are estimated to be 

$41.8 million. 
11 

Table 16. Nationwide Annualized Costs for CMP Retrofit - All Sources 

Electroplating Type With Add-on 

Controls, $/yr

Without add-on 

controls, $/yr 

Total Nationwide 

Annualized Cost, $/yr

Hard chromium electroplating $11,049,600 $2,871,600 $13,921,300 

Decorative chromium electroplating $3,565,500 $17,113,600 $20,679,100 

Chromium anodizing $1,635,100 $5,627,700 $7,262,900 

Total $16,250,300 $25,612,900 $41,863,300 

IV. Cost Effectiveness for CMP Retrofit

 Table 17 presents the cost effectiveness for retrofitting CMP on all existing tanks that are 

subject to the Chromium Electroplating NESHAP. The cost effectiveness was estimated to be 

$36.9 million per ton for hard chromium electroplating plants, $249 million per ton for 

decorative chromium electroplating plants, and $431 million per ton for chromium anodizing 

plants. Overall cost effectiveness was estimated to be $87.7 million per ton. 
12 

Table 17. Cost Effectiveness for CMP Retrofit 

 Model Plant Size 

Non-CMP Add-on Control Without Add-on Control All Source

Nationwide 

annualized 

costs, $/yr 

Nationwide 

emission 

reductions, 

lbs/yr 

Cost 

effectiveness, 

$/lb 

Nationwide 

annualized 

costs, $/yr 

Nationwide 

emission 

reductions, 

lbs/yr 

Cost 

effectiveness, 

$/lb 

Nationwide 

annualized 

costs, $/yr 

Nationwide 

emission 

reductions, 

lbs/yr 

Hard Chromium Small $8,960,916 350 $25,600 $2,506,194 48.7 $51,500 $11,467,110 399 Medium $2,088,713 317 $6,600 $365,433 39.0 $9,360 $2,454,146 356 

 Total $11,049,600 667 $16,570 $2,871,600 87.7 $32,740 $13,921,300 754 

Decorative Chromium Small $1,500,240 6.9 $216,600 $12,426,917 27.7 $448,370 $13,927,158 35 Medium $1,012,662 10 $106,260 $3,952,982 18.9 $209,510 $4,965,644 28 Large $1,052,643 56 $18,640 $733,699 46.6 $15,750 $1,786,342 103 

 Total $3,565,500 73 $48,890 $17,113,600 93.2 $183,690 $20,679,100 166 

Chromium Anodizing Small $456,154 1.2 $391,080 $3,608,791 4.7 $773,490 $4,064,946 5.8 Large $1,178,993 15 $77,530 $2,018,920 12.7 $159,320 $3,197,914 28 

Total $1,635,100 16 $99,870 $5,627,700 17.3 $324,600 $7,262,900 34 

All Source Categories 

TOTAL $16,250,300 756 $21,490 $25,612,900 198.2 $129,220 $41,863,300 954 
13 

V. References

1. Memorandum from R. Marinshaw, RTI International, to P. Mulrine, EPA/OAQPS. 

Estimated Number of Chromium Electroplating Plants. May 24, 2010. 

2. U.S. EPA. Chromium Emissions from Chromium Electroplating and Chromic Acid 

Anodizing Operations -- Background Information for Proposed Standards, Volume I (EPA 

453/R-93-030a). U.S. Environmental Protection Agency, Research Triangle Park, NC. July 

1993. 

3. U.S. EPA. EPA Air Pollution Control Cost Manual, EPA/ 452/B-02-001. U.S. 

Environmental Protection Agency, Research Triangle Park, NC 2002. 

4. Letter from E. Sithes, Oskar Environmental Inc, to J. Cunningham, RTI International. Cost 

of HEPA Filter. January 29, 2010. 

5. U.S. Bureau of Labor Statistics. 2009. Employment and Wages for Plating and Coating 

Machine Setters, Operators and Tenders, Metal and Plastic. May. 

6. U.S. EPA. Technical Assessment of New Emission Control Technologies Used in the Hard 

Chromium Electroplating Industry, EPA/ 453/R-93-031. U.S. Environmental Protection 

Agency, Research Triangle Park, NC. July 1993. 

7. South Coast Air Quality Management District. Final Socioeconomic Assessment for 

Proposed Amendments to Rule 1469 – Hexavalent Chromium Emissions from Chrome 

Plating and Chromic Acid Anodizing Operations and Proposed Rule 1426 – Emissions from 

Metal Finishing Operations. 2003. 

8. Memorandum from R. Marinshaw, RTI International, to P. Mulrine, EPA/OAQPS. 

Nationwide Costs for Conversion to Non-PFOS Fume Suppressants. August 16, 2010.