The following substances have been delisted from the Toxics and Hazardous Substance List (301 CMR 41.00) effective reporting year 1995:
Copper, nickel, chromium, cobalt or manganese in a solid or molten metal alloy, but not including aerosols, where aerosols are defined as particles less than 50 um (microns) in diameter.
Questions have been raised regarding implementation of this delisting. This guidance has been produced to assist the regulated community in complying with TURA. If you have any remaining questions after reading this document, please contact the Department of Environmental Protection (MassDEP) for compliance assistance or the Office of Technical Assistance for further information.
For the purposes of determining what a metal alloy is, a useful definition of a metal alloy is given by "An Encyclopedia of Metallurgy and Materials" (MacDonald and Evans, 1984):
"An alloy is a substance possessing metallic properties and composed of two or more elements of which at least one must be a metal. The term refers to those cases where there is an intentional addition to a metal for the purpose of improving certain properties."
The delisting covers metal alloys in solid or molten form, such as copper in bronze and brass, and nickel and chromium in stainless steel.
This delisting does not extend to dissolved metals, metal alloys in aerosol form, metal alloy particles less then 50 microns in diameter, or any of the five metals in non-alloy form; i.e., a metal containing a low level of impurities is NOT an alloy. For example, wire comprised of 99+% copper and less than 1% impurities is considered to be essentially pure copper, and not an alloy.
The use of metals in pure form can be subject to reduced TURA reporting requirements and exempted from TURA planning and fees provided specific requirements are met. Detailed information on this expanded article exemption can be found in the "BWP 94-014 Policy for TURA Reporting and Planning for Certain Metalworking Operations" and the "Recycling Activity Report Form". Both of these documents can be obtained from MassDEP by calling the TURA Program at 617-292-5982.
The 50 micron size which describes metal alloy aerosols and particles refers to the particle size of the metal alloy, not the particle size of the individual listed metals.
Specific Process Questions
The following sections provide guidance for specific processes in which metal alloys are used:
- Etching processes. When a metal is removed from the metal alloy stock through chemical processing, the resultant metal salt is reportable if it is produced in threshold quantities (in this case, the metal salt is "coincidentally manufactured"). The 25,000 pound threshold would apply if the metal salt is the only reportable chemical; the threshold drops to 10,000 pounds if a facility is using other reportable chemicals. It should be noted that the entire weight of the metal salt is considered when determining whether a threshold has been met, and not just the amount of the metal in the salt. The stock itself, if it is a metal alloy as defined above, is not reportable.
- Electropolishing operations. The metal salts in solution are reportable as "coincidentally manufactured" if they are produced in threshold quantities. Again, the stock itself, if it is a metal alloy as defined above, is not reportable.
- Grinding Operations. The listed metals are not exempt from reporting when contained in aerosols of a metal alloy, i.e., particles less than 50 microns in diameter (in this case, the metal is reported as "processed"). These metals are reportable if they are present in a metal alloy aerosol in threshold quantities. When determining whether the reporting threshold has been exceeded, only the weight of the listed metal is considered, and not the total weight of metal alloy aerosol. The stock itself, if it is a metal alloy as defined above, is not reportable.
- Multiple processes. In a production unit where the metal alloy stock is being used in several different processes, none of the stock is reportable if it is a metal alloy as defined above. However, the individual production processes may produce metal alloy in aerosol form or metal salts in solution. Those aerosols and metal salts in solution would be reportable if produced in threshold quantities, as described above.
- Alloys in powdered form. If a metal alloy is used in particle form, the facility will need to perform a particle size analysis to determine the amount of material less than 50 microns in size. The listed metals (e.g., Cr, Cu) are reportable if they are present in metal alloy particles less than 50 microns in size in threshold quantities. When determining whether the reporting threshold has been exceeded, only the weight of the listed metal is considered, and not the total weight of metal alloy particles.