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Does thermal-only metal coloring subject us to 40 CFR 433?

September 27, 2012

Q. A regulator has posed the question as to whether or not using dry heat or adding some steam during a final coloring process to saw blades to get an aesthetic straw or black look is considered "chemical metal coloring" in 40 CFR Part 433 which would then subject the facility's wastewater as categorical. There is no wastewater generated in the thermal coloring process whether or not steam is used. Anyone run across this before?

Jim Kirlin
consultant - Greenville, South Carolina, USA

September 28, 2012

A. The bleep regulator should not be asking you. He should be quoting page paragraph and line number of the appropriate regs.
I cannot imagine how they could come up with that. By definition it is not a solid waste at least as I knew it.
They might be able to give you grief on air quality at the stack.

James Watts
- Navarre, Florida

October 2, 2012

Q. HI, thanks for you response. I may have left out some info that may be useful.
It's not an issue of solid waste. 40 CFR Part 433 deals with wastewater under the Clean Water Act. The EPA has decided, but I do not think they completely understood the process having never laid eyes on it. I'm looking for a precedence where they determined that metal coloring through thermal techniques alone qualifies as "chemical metal coloring" as defined in the effluent guideline and the development document for the effluent guideline. Thanks.

Jim Kirlin
- Greenville, South Carolina, USA

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