UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

Terri Zick, CHMM 

CTI & Associates, Inc. 

12482 Emerson Drive 

Brighton, MI 48116 

Dear Ms. Zick: 

Thank you for your e-mail of September 9, 2003, to James Michael of the Environmental 

Protection Agency (EPA) in which you ask for a regulatory clarification regarding the 

applicability of the F006 classification to wastes generated from the chemical etching of 

magnesium. 

In your e-mail, you stated that you believe the wastes generated from the chemical etching 

of magnesium fall outside the definition of the F006 listing. You base this view on the fact that 

the chemical etching does not occur on a common or precious metal as defined in the listing 

background document (11/14/80) and the development document for proposed and existing 

source pretreatment standards for the electroplating industry (EPA, 2/78). 

The applicability of a Resource Conservation and Recovery Act (RCRA) hazardous waste 

listing is determined in the first instance by the regulatory language. The F006 listing covers 

wastewater treatment sludges from certain electroplating operations. The listing applies to 

chemical etching, among other activities, and only excludes the chemical etching of aluminum. 

Magnesium etching is not excluded from the F006 listing. In a December 2, 1986, Federal 

Register notice, EPA further interpreted the F006 language to apply to "common and precious 

metals," but this interpretation applied only in certain instances, and did not affect chemical 

etching. Specifically, EPA's interpretative rule at 51 FR 43351 (December 2, 1986) states, "The 

F006 listing is (and always has been) therefore, inclusive of wastewater treatment sludges from 

only the following processes: (1) Common and precious metals electroplating, except tin, zinc 

(segregated basis), aluminum, and zinc-aluminum plating on carbon steel; (2) anodizing, except 

sulfuric acid anodizing of aluminum; (3) chemical etching and milling, except when performed 

on aluminum; and (4) cleaning and stripping, except when associated with tin, zinc, and 

aluminum plating on carbon steel." Thus, while the scope of electroplating processes is limited 

to common and precious metals with the exceptions as noted above, there are no such limitations 

for the remaining processes (anodizing, chemical etching and milling, and cleaning and 

stripping). Therefore. there is no exception for specific metal types from the listing for any of the 

remaining processes. Thus, wastewater treatment sludges generated from chemical etching of 

magnesium are subject to the F006 listing. 

Recycled/Recyclable • Printed with Vegetable Oil Based Inks on 100% Recycled Paper (20% Postconsumer) 
We appreciate your concern that the background listing document didn't specifically 

mention the chemical etching of magnesium. However, EPA's listings are defined by the 

regulatory language, and background documents don't necessarily catalogue every waste material 

that fits within that definition. In those situations where processes aren't specifically mentioned, 

EPA follows the straight reading of the regulations. 

You indicated that analysis of the wastewater treatment sludge does not show the 

constituents of concern for the F006 listing. If you believe that the wastewater treatment sludge 

does not contain any of the constituents of concern for the F006 listing, you may be eligible for a 

"delisting." Delisting is the procedure by which you can remove a waste from a hazardous waste 

listing. Since the State of Michigan is not authorized to make delisting decisions, you will need 

to work with EPA Region 5 if you wish to explore this option. The Regional contact for 

delisting is Judy Kleiman. Judy can be reached at (312) 886-1482. 

If you have any additional questions, please contact James Michael of my staff at (703) 

308-8610. 

Sincerely, 

Robert Dellinger, Director 

Hazardous Waste Identification Division 

cc: James Michael, HWID, OSW 

Judy Kleiman, Region 5, USEPA 

Jack Schinderle, Michigan DEQ