Some businesses fall under local Industrial Wastewater permit requirements. That is because in order to dispose of some types of industrial process wastewater to sewer, the generator needs to adhere to local and Federal discharge limits. These requirements come from the National Pollutant Discharge Elimination System (NPDES) limits set by the Federal government. In basic terms, the rule sets limits to pollutants (individual constituents in the wastewater such as heavy metals, oils and grease) that can be discharged to sewer. Municipal sewer districts and others must meet discharge limits and so have a keen interest in what upstream dischargers are adding to the water that they treat. One sort of true saying about pollution is that “the solution to pollution is dilution” and treatment of industrial wastewater in a way relies on this being true. Your discharge limits are generally calculated based on the amount of throughput in the pipe; add too much of the regulated pollutants into the pipe and the treatment plant may be unable to meet their own NPDES permit discharge limits. There are of course the so-called “‘midnight dumpers” who illegally discharge excessive amounts of pollutants to the sewer system – sometimes those with NPDES permits but often the result of totally clandestine activities such as pumper trucks discharging to a street storm drain.
Here’s an example of where practice by an EHS (environmental, health and safety department) failed to meet best practice or regulatory requirements. Years ago we conducted a compliance audit at a world-renowned research facility. In that facility chemists worked with radioactive substances. In the lab, despite that researchers took adequate precautions to protect themselves from possible exposure to Alpha emitters (low-level Alpha particle radioactive materials) while conducting experiments, they had been told that it was OK to dump the materials down their lab sinks when the experiment was completed. Our investigation determined off-the-scale radioactivity at each lab sink drain; the meter pegged and anyone with their face over the drain would receive a face full of concentrated Alpha radiation. We can understand the rationale of the EHS departments advisory as Alpha emitters tend to have rather short half-lives. But they had not counted on accumulation of these materials in the traps of each lab sink drain. And pity the institute’s plumbers who if they ever broke apart the sink drains during maintenance would be highly exposed to radioactive contaminants. The essence of this example is that even supposedly correct and reliable information from EHS professionals can be dead wrong. The overarching lesson is to be certain who you have in charge making command decisions. As always, we can help you assess your regulatory compliance and the viability of your EHS management systems.
So it is important to ensure that your industrial activities meet NPDES rules. In order to prevent accidental discharge of industrial wastewater to sewer or a waterway, ensure that possible sewer connections and discharge points are well controlled.