Avoiding the Environmental Risks of Alloy Blocking Systems

Alloy - the material used in most laboratories for blocking. It has become a major environmental compliance issue facing optical laboratories. As a result, lab managers are increasingly abandoning alloy for the more environmentally-acceptable non-alloy blocking technology. The switch, however, is not without cost.
In addition to a substantial capital expenditure and the retraining of employees, some labs using non-alloy systems experience lower productivity per blocking station, increased deblocking problems, and difficulty in using the system on glass lenses.
As an environmental management professional, I ardently condone the substitution of hazardous or pollution-causing materials or processes with non-hazardous and “environmentally friendly” ones. However, you may not be in a position to invest in a new blocking technology, implement a major process change, or perhaps you prefer the performance that alloy blocking provides. So, before presenting a solution, to this dilemma, let’s first make sure everyone understands the problem.

Alloy’s Potential As a Hazardous Waste
The alloys most commonly used in blocking are the 117- and 158-Alloys, named for the approximate temperature Fahrenheit at which they melt. Two of their primary components are the metallic elements lead and cadmium. Both are toxic to humans when consumed through contaminated drinking water or food. When released into the environment, they are persistent, they never degrade and cannot be destroyed.
To protect the public from environmental contamination, Congress passed several environmental laws affecting nearly every industry in the country. Two laws that are of concern regarding this issue are the Resource Conservation and Recovery Act (RCRA) and the Clean Water Act (CWA). Under RCRA, the Environmental Protection Agency (EPA) and State regulations declare that if a waste tests positive for any of 8 metals (including lead or cadmium), or any of 32 other substances, the waste is considered toxic and must be specially disposed of as hazardous waste. The test performed is called the Toxicity Characteristic Leaching Procedure or TCLP. If the TCLP of a waste exceeds 5.0 milligrams per liter (mg/L) lead or 1.0 mg/L cadmium, it is a hazardous waste under RCRA.
Under the CWA local sewer districts and wastewater treatment authorities have the responsibility for establishing the type and concentration of pollutants that are allowed to be discharged by industries into municipal sewer systems. Most districts have legal discharge limits for lead and cadmium concentrations in industrial wastewater effluents.
Failure to dispose of a hazardous waste properly, or to exceed effluent discharge limits, can subject the lab (even a small operation) to severe civil penalties (up to $25,000 per day per violation). However, the trend among enforcement agencies now is to pursue plant managers, company officers and owners with personal and even criminal liability in addition to punitive damages against the company.

Handling Reclaim Tank Water
Having developed environmental compliance programs for several optical laboratories in the mid-1990s, I found that the environmental issues associated with the use of alloy are consistent and predictable. For those labs that use alloy blocking systems, I offer the following observations and advice:

1. Untreated alloy reclaim tank wastewater contains high concentrations of cadmium and lead (usually exceeding 100 mg/L) and will likely test out as hazardous waste. Therefore, it should not be discharged down the drain or containerized and disposed of with the other solid waste.

2. Alloy reclaim tank water is not adequately treated in most wastewater treatment equipment used by optical laboratories. These systems are designed to remove suspended solids such as polishes from the wastewaters. Mixing alloy reclaim tank water with other waste liquids to be treated prior to disposal can render all effluent from the process unsuitable for legal discharge to the sewer system, can cause all filtered solid residuals to test out as hazardous waste, or both.

Alternative Treatments
So, is there an alternative for labs that choose for cost or technical reasons not to replace their existing alloy blocking systems with an alternative “wax” technology? The answer is YES. Effective treatment of alloy tank wastewater can be accomplished using an inexpensive chemical treatment additive and simple equipment. A product developed for this purpose, Cad-Con 1000™, converts cadmium and lead in alloy reclaim tank water to an insoluble, non-polluting form that is stable, non-hazardous, safe and legal to dispose of as non-hazardous waste. Research has demonstrated that alloy reclaim tank wastewater containing up to 280 parts per million cadmium and over 250 parts per million lead tested essentially zero (below the detection limit) when analyzed by the TCLP method following treatment. Here’s how it works:
1. Alloy tank wastewater is drained into a suitable container (a 5-gallon plastic bucket works fine).
2. The proper dosage (approximately one cup for 5 gallons) of Cad-Con 1000™ is added and thoroughly mixed.
3. The reaction occurs instantly. The cadmium and lead in solution and in the small particles that give the wastewater that “muddy” look are stabilized and begin to settle to the bottom of the container.
4. Then, one of two possibilities occurs:
(1) If the facility has an in-plant wastewater treatment unit that removes suspended solids, the treated alloy tank wastewater can simply be discharged to the treatment unit along with other wastewaters for treatment. It will not contaminate the effluent or the residual solids from that process because the cadmium and lead are stablized and will not contaminate the other wastewater.
(2) If the facility has no other treatment unit, simply allow the water to clarify for 24 hours (solids settle to the bottom of the container leaving clear water above). The clear water is simply poured off down a drain taking care to retain as much of the settled solids in the bottom as possible. The remaining solids are disposed of along with other non-hazardous solid waste.

Determine Your Compliance Status
Note that compliance is always the responsibility of the owner, operator, and/or manager of the optical laboratory. No vendor supplying treatment equipment, products, or even “environmentally friendly” substitutes can guarantee compliance. It is, and always will be, YOUR responsibility. If you desire to have proof of compliance on hand, have a sample of the clear water tested for cadmium and lead and the filtered solids tested for TCLP cadmium and lead by a qualified environmental laboratory. Keep the written results on file and ready to show an agency inspector.

9

REASONS TO

USE CAD-CON 1000™

1. You want a total solution for Alloy Tank Wastewater. 
Cad-Con 1000™ provides reliable treatment of tank waters and wastes contaminated with blocking alloy metals. It also works independent of the pH and over a wide range of acidic and alkaline waters.

2. Effective treatment for the hazardous waste component is a must.
In an extreme case study, Cad-Con 1000™ reduced alloy tank water with 280 mg/l cadmium and 250 mg/l lead to a TCLP of essentially zero (below .002 mg/l). The threshold limits for hazardous waste are 1 mg/l cadmium and 5 mg/l lead.

3. Effective treatment for the water component is also a must.
The liquid portion (water) must be suitable for discharge to your local sewage treatment plant. Dissolved cadmium and lead are typically reduced well below your local sewer discharge limits.

4. You need something that works consistently each time it is used.
Because Cad-Con 1000™ is used as a batch treatment of your waste:

• It is always full strength,
• It never looses potency,
• Its effectiveness is never diminished over time.

5. You need a product that’s easy to use. Cad-Con 1000™ is easy to use, simple to incorporate into your existing process. Just:

• Drain your alloy reclaim tank into a suitable container,
• Treat (mix in Cad-Con 1000™ and let stand),
• Clarify (filter or let sediment settle to the bottom),
• Dispose (clear water to drain, sediment to trash).

6. You don’t need any additional problems.
And you won’t get any when you use Cad-Con 1000™:

• Its non-hazardous,
• It generates no residual hazardous wastes (like filters to send back),
• It generates no noxious odors or gases,
• It generates no foaming, and
• It works with your Panhandler treatment unit or other equipment (If you use it).

7. You want to keep your compliance costs to a minimum.
Cad-Con 1000™ is inexpensive; For the typical 5-gallon alloy reclaim tank, Cad-Con 1000™ can provide absolute compliance protection for less than $4.00 per week.

8. You don’t want to risk an EPA violation.
Improper disposal of alloy tank water is the optical lab’s most serious environmental risk and state and federal enforcement agencies are increasingly pursuing violators with personal and even possiblecriminal liability.

9. If you’ve read this far, you obviously have a need.
So what are you waiting for? Order before June 1st and receive one of the following generous discounts.  Just call 513-779-2999 or send an e-mail to Geo-Chem@cinci.rr.com:

• Order 1 bucket (8 lbs) and get 10% off the normal $199 price (save $20)
• Order 2 buckets get 15% off both buckets (save $60 off the regular price)
• Order 3 buckets get 20% off all 3 buckets (save $120 off the regular price)
• Order 4 buckets get 25% off your entire order (save $200)  

 CAD-CON 1000™

Waste Treatment Additive

Effective, reliable treatment for Optical Laboratory alloy reclaim tank wastewater

Manufactured & Distributed by: Geo-Chem Technologies, 7125 Lakota Ridge Drive, Liberty Twp, OH 45011

E-mail: Geo-Chem@cinci.rr.com                                       Telephone: (513) 779-2999