---- "Jack R." <jack007@COMCAST.NET> wrote:

> Our local city/water department said it is fine to pour used anti-freeze down the drain to the sanitary sewer system.
> Also, see other water departments approve of this... Best to check with your local city to see if they approve.
> http://www.cityofames.org/worksweb/operations/StormSewers/StormSewerInformation.htm
> Safe Disposal for Large Amounts of Anti-freeze
> The anti-freeze from a single radiator can be safely disposed of in a sanitary sewer and treated by the City's wastewater treatment plant. However, large quantities from commercial or fleet maintenance programs will upset the plant's biological system and are prohibited.
>
> Any anti-freeze discharge directly into a river or stream can cause environmental damage to fish and other aquatic life, and is not allowed. Dry weather compounds the problems from these illegal discharges.
>
> When there is very little water in area streams, there is virtually no dilution occurring. During dry conditions, wildlife are drawn to any available water they can find. Also, the lower water levels make improper discharges much easier to spot.
>
> NOTE: DO NOT DISPOSE IN STORM SEWER OR IF YOU HAVE A SEPTIC SYSTEM!!!

Many entities allow sanitary sewer disposal of antifreeze.  That does not mean that it is a reasonable thing to do.  Used antifreeze contains metals in addition to the organics that the sewage treatment plant may or may not handle adequately via the microbial breakdown by which it handles other organics.  Fact is, the environmental microbiology course I took, we sampled radiators at junkyards, and cultured the samples in the lab with ethylene glycol as a substrate.  Excellent growth, and evidently good breakdown.  However, that does not mean that those microbes are present in the receiving sewage system, and it does not mean that other toxics beyond ethylene glycol are absent.

If a disposal agent will take it, that is the place for it to go.

David McNeely