As the quality manager of a large job shop metal finishing facility and recent restructuring, I now have responsibility for environmental issues. While we knowingly do not purchase any lead or lead containing products, nonetheless, we know lead is present due to detectable concentrations found in our wastewater treatment filter press cake; lead is always non-detectable in our wastewater discharge. How do I better document whether or not I need to report for lead?
Q. As the quality manager of a large job shop metal finishing facility and recent restructuring, I now have responsibility for environmental issues. As I have been going through my predecessors’s files, in preparation for the 2006 Form R report, I found a note stating we do not need to report for lead releases but with no supporting documentation. While we knowingly do not purchase any lead or lead containing products, nonetheless, we know lead is present due to detectable concentrations found in our wastewater treatment filter press cake; lead is always non-detectable in our wastewater discharge. Furthermore, we only process carbon steel and aluminum and none of the material safety data sheets show lead as a constituent. How do I better document whether or not I need to report for lead? J.T.
A. Determining whether or not to report lead or lead compounds under SARA 313 Toxic Release Inventory Reporting (aka Form R) can be particularly challenging for metal finishers. Since lead and lead compounds have been classified as “persistent, bioaccumulative and toxic” (PBT), they have a very low reporting threshold of 100 pounds (except lead contained in stainless steel, brass or bronze alloys which still have the 25,000 pound reporting threshold) and the de minimis exemption does not apply. The de minimis exemption, such as 1% for manganese or 0.1% for lead, allows one to ignore concentrations of reportable concentrations below the de minimis level when determining how much of the chemical you used, processed or manufactured. While many types of carbon steels do not contain any detectable lead, others can contain lead, such as “leaded” bar stock used in some machining applications.
Since no de minimis exemption applies to lead and lead compounds, and material safety data sheets typically do not show concentrations in the parts per million range, we have turned to analysis to provide documentation as to whether or not to report. While USEPA says you are not required to analyze to determine whether or not to report or to determine how much, if any, of the chemical is released, we have found it very cost effective, especially for metals such as lead. Instead of hours and hours of research, the cost to analyze a liquid or solid sample for lead only costs between $15 and $25. Based upon numerous samples of wastewater treatment filter press cake and grinding waste, we have found the lead content can range from 0.01–2.5% by weight of the iron content.
From our experience, here is the general process that I propose you consider:
- While likely not feasible for job shops servicing a variety of customers, have your customers contact their steel suppliers and obtain the steels’ specifications, which can give you constituent concentrations well below those provided on the MSDS. One of our captive metal finishing clients has only one steel supplier and they were able to document the absence of lead in their steel.
- Consider sampling and analyzing your wastewater treatment filter press cake, any waste pickling or cleaners sent off-site for disposal, dust collector wastes, grinding sludges or other wastestreams that contains significant amount of iron. We recommend analyzing at least three samples over a period of time for lead and iron to obtain a good average.
- Calculate how much lead AND lead compounds are in these wastes. Assuming your filter press cake contain lead hydroxide (a lead compound), you need to multiply its lead concentration by 1.115. Remember to do this for other possible lead compounds such as lead oxide, lead sulfate, etc. If the amount of lead OR lead compounds in your wastestreams exceeds 100 pounds, then definitely report.
- Even if the amount of lead in your wastestreams is less than 100 pounds, you may still need to report under this rationale—the amount of lead in your wastestreams is only a fraction of the amount you “processed” through your metal finishing operations. For example, if you document by analysis that lead is, on average, 0.05% of your iron content in your wastestreams and you processed 1,000,000 pounds of steel parts last year, the amount of lead that you “processed” can be estimated by taking 0.05% × 1,000,000 pounds = 500 pounds; since 500 is greater than 100 pound threshold, we would report lead.
Whenever we are in doubt whether or not to report, we take the conservative approach and report. Once our calculation worksheets for the release reporting are set up, it does not take much time to prepare the Form R. Fortunately, for the vast majority of metal finishing facilities that do report lead, we have found the amount of lead or lead compounds “released” into the environment is very small; most of our clients have air and wastewater releases well under one pound per year. For more information, you can visit the USEPA on PBT reporting, www.epa.gov/tri/lawsandregs/pbt/pbtrule.htm.
Hope this helps.
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