Date: May 25, 2010

Subject: Estimated Number of Chro mium Electroplating Plants Emission Standards Technical Suppor t and Post Promulgation Activities EPA Contract No. EP-D-06-118; EPA Work Assignment No. 4-6 RTI Project No. 0210426.004.006

From: Richard Marinshaw

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

The purpose of this memorandum is to provide the basis for the estimated 1,770 plants in the U.S. that are subject to the national emission standards for h azardous air pollutants (NESHAP) for Hard and Decorative Chromium Electroplating and for Chromium Anodizing Tanks (40 CFR 63, subpart N). Section I of this memorandum describes the data used to develop the estimated numbers of plants, and Section II explains how the estimates were derived.

I. Background

RTI International (RTI) bega n compiling data on the chromium electroplating industry in June 2003 under Work Assignment 1-18 of EPA C ontract No. 68-D-01-079. Data were obtained from EPA Regional Offices, State and local agen cies, and several databases, including the National Emission Inventory (NEI) database, the Toxic Release Inventory (TRI) database, the

National Metal Finishers Resource Center online database, and th e Thomas Register On-line. The data obtained from many of these information sources consisted of plant names, addresses, and the type of electroplating performed. In some cases, data on electroplating tank operating parameters also were obtained. The data were co mpiled in an Access database, hereafter referred to as the Electroplating Database. The database has been periodically updated as new data have

become available.

In March 2004, RTI began working on the Plating and Polishing Area Source NESHAP. Because many of the processes and sources that were covered by the Plating and Polishing source category were co-located at facilities that are subject to the Chromium Electroplating NESHAP, the data collected for Plating and Po lishing were entered into the Electroplating Database. In 2006, an information collection re quest (ICR) was developed for the Plating and Polishing Source Category and transmitted to more than 1,100 companies. The ICR questionnaire requested information on electroplating and non-electroplating processes, tank design and operating data, use of plating chemical s and other materials, and emission controls. Because tanks subject to the Chromium Electropl ating NESHAP would not be subject to a rule for Plating and Polishing, the ICR instructed plan ts to indicate if the pl ant performed chromium electroplating, but respondents we re not required to provide any further data on chromium electroplating operations.2

When the Plating and Polishing ICR maili ng list was developed, the Electroplating Database included information on approximately 2,600 plants. For about 1,200 of the plants, the available information indicated that the only type of electroplating performed at the plant was chromium electroplating. Those plants were scre ened out of the mailing list for the Plating and Polishing ICR. After further sc reening of the data, a final mailing list was prepared. The mailing list included about 1,150 companies, repr esenting just over 1,200 plants. The ICR was transmitted in May 2006, and a total of 606 ICR ques tionnaires were completed and returned to EPA. In other words, data were received for approximately 50 percent of the plants that were sent questionnaires. Approximate ly 100 questionnaires were retu rned to EPA as undeliverable; and EPA was informed that roughly another 100 pl ants were either clos ed or did not perform plating or polishing; the status of the other 400 plants that were sent questionnaires is unknown. After updating the Electroplating Da tabase to account for the 200 plan ts that are either closed, do not perform electroplat ing, or were undeliverable, the Electroplating Database included information on 2,417 plants that were assumed to be in operation. Of these, 1,171 plants were indicated as performing only chromium electropl ating (chromium only plan ts), and 1,246 plants were indicated as performing some other type of electroplating (other el ectroplating plants). However, it was unknown the type of chromi um electroplating performed by the 1,171 chromium only plants, and it was unknown how many of the other electroplating plants performed chromium electroplating. Using the da ta on electroplating proc ess type that were available for some of the plants, and the data compiled for the Plating and Polishing NESHAP,

the number and distribution of chromium electr oplating plants were estimated. The following section describes the methodology used for the estimates.

II. Methodology for Estimating Number of Plants Nationwide

For the chromium only plants listed in the Electroplating Database, the type of process was identified for a total of 417 plants. Table 1 summarizes the distribution of these plants by the three process types covered by th e Chromium Electroplating NESHAP.

Table 1. Type of Electroplating Pe rformed by "Chromium Only" Plants

Process type No. of plants Percent of total

Hard chromium 204 48.9%

Decorative chromium 145 35.0%
Chromium anodizing 67 16.1%

Total 417 100%

For the other electroplating plants listed in the database, the data from the Plating and Polishing ICR responses were used to estimate th e distribution. Although the questionnaire did not request detailed data on chro mium electroplating, it did require plants to indicate if they performed chromium electroplating or anodizing. Table 2 summarizes the distribution of these plants according to process.3

Table 2. Type of Chromium Electroplating Reported in Plating and Polishing ICR Responses

Process type No. of plants Percent of total

Hard chromium 107 17.7%

Decorative chromium 160 26.4%
Chromium anodizing 27 4.5%
No chromium electroplating 312 51.5%

Total 606 100%

By combining the percentages of chromium electroplating plants from the above distributions and applying them to the number of plants in the Electroplating Database, the number of each type of chromium electroplat ing plants nationwide was estimated. Table 3

summarizes the results.

Table 3. Estimated Number of Chromium Electroplating Plants Nationwide

Process Total Hard

chromium Decorative

chromium Chromium anodizing
No. of chromium only plants in database 1,171
Percentage for each process 48.9% 35.0% 16.1%
Resulting number of plants 573 410 188
No. of other plants in database 1,246
Percentage for each process 17.7% 26.4% 4.5%
Resulting number of plants 220 329 56
Total number of plants 793 739 244

Total (rounded to nearest 10) 1,770 790 740 240