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What's our zinc level?

I have been asking and asking and no one can seem to tell me what the Michigan levels for zinc are. I am trying to find this out to impress my boss as he has not found it yet and we have been asked this question a few times by different field techs this year. we work at a small town lab with only four employees. just asking thanks for any help.

trying to impress,

Trevor Macleod
young apprentice - Traverse City, Michigan, U.S.A.
February 25, 2009

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First of three simultaneous responses --

Do you mean; what is the level in your tap water, or what is the permissible discharge limit?

If the first - contact your local DEP or water authority. The highest level deemed acceptable is 5 mg/l.

If the second, speak to your local sewer authority. With Zn, they usually follow the Federal Categorical limit, which is 2.61 mg/l.

Dave Wichern
Consultant - The Bronx, New York
February 27, 2009

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Second of three simultaneous responses --

In what? water or air or?

James Watts
- Navarre, Florida
February 27, 2009

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Third of three simultaneous responses --

Are you talking about allowed levels of zinc in waste water?

Thomas E. Kidd
- Budapest, Hungary
March 2, 2009

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March 3, 2009

Interesting numbers, Dave.

So you might not be allowed to discharge tap water into the sewer? You could drink it, but not dump it.

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.

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March 4, 2009

Bill,

I don't doubt that. When I was in college I worked for an environmental lab and was routinely shocked at discharge levels vs. tap water. I remember for one that the chlorine in tap water is more than 3 times the allowable discharge.

David J. Wolf
Medina, Ohio

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March 6, 2009

Yes Bill, it's quite absurd. It was always one of those peculiarities of US environmental laws that came up in conversation over drinks at AESF meetings.

They have changed a few things to bring them into line with, well, sanity. Lots of municipalities have raised the permissible pH discharge limit to 12. And, when receiving waters are saline or brackish, they've relaxed the fluoride discharge limits considerably, since there's plenty of fluoride in there to begin with.

Dave Wichern
Consultant - The Bronx, New York

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The Environment Agency here is proposing a new limit for discharge to water courses for rain water running off industrial land such that merely turning on the fresh water tap (town supply) and running to the drain would exceed the limit.
And even that would be at a lower limit that the nearest watercourse (a small stream).
Sometime these matters get out of perspective.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

March 7, 2009