Other EPA Rules
Additional restrictions on hard chrome
plating
In addition to air contaminants, the EPA also
regulates wastewater (under the Clean Water Act),
groundwater contamination, and disposal of hazardous waste.
All of these have an important impact on hard chrome plating
operations. Platers must now ensure that:
-
Cr6+-contaminated
wastewater such as rinse water is properly treated
before discharge to the sewer
-
The plating plant is
constructed to prevent spills that could cause
groundwater contamination (which has happened beneath
many older chrome plating plants)
-
The plating solution or
sludge and any Cr6+-contaminated materials
such as masking materials, air filters, and solids and
liquids from air-handling systems are recycled or
properly disposed of.
Nickel – next on the hit list?
The Clean Air Act currently requires the EPA
to control 188 hazardous air pollutants, also known as toxic
air pollutants or air toxics, which are believed to cause
adverse environmental and ecological effects. Of these
pollutants, the so-called EPA Toxic 17 have been singled
out as toxics of the greatest potential concern. This list
of targeted materials includes compounds of the four metals
– lead, mercury, cadmium and chromium – whose use in
products has been strictly limited by the new European ELV
and RoHS directives, and also nickel and its compounds.
Inhaled
nickel dust is classified by the EPA as a class A human
carcinogen, largely based on studies of nickel refinery
workers. While soluble nickel salts such as those used in
plating have not yet been evaluated for potential
carcinogenicity by the EPA, they have already been declared
as carcinogens by the State of California, which
now regulates all new nickel plating installations – both
electroless and electrolytic – in the state. In the EU, a
number of restrictive controls have been instituted on
nickel emissions, both into the air and the water supply.
Furthermore, nickel is known to cause a wide range of
allergies. For all these reasons, nickel and its salts are
likely to become increasingly regulated worldwide.
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