The water and wastewater industry faces a constant and evolving challenge to keep pace with the treatment of new pollutants. Many factors contribute to this issue, including pharmaceuticals in our surface waters and the effects of agricultural runoff. The rate of change in the industry is evidenced by the U.S. Environmental Protection Agency’s (EPA) addition of 97 new contaminants, including pesticides and disinfection byproducts, to the Candidate Contaminant List 4 (CCL4) issued in 2016.
As the ability to detect contaminants advances and we understand more about how these contaminants affect human health, it can only be assumed that new contaminants will continue to be added to the list. The industry must be able to respond accordingly with testing and remediation solutions in order to keep our water supplies safe and our outdoor environment healthy.
Both water and wastewater treatment are and will continue to be impacted. In wastewater, for example, some of the newly identified contaminants and pollutants are problematic because of the nutrient load they contribute when discharged to receiving bodies of water. This load can have a negative impact on human and/or aquatic life when they enter those water sources.
Another example relates to pharmaceuticals. While pharmaceuticals bring enormous benefits to society and human health, some are bio-persistent and do not break down when processed through the body. It has been shown that certain bio-persistent pharmaceuticals can change the sex of aquatic life and over time may also create health concerns for humans if they are introduced into drinking water supplies. As a result, discharge requirements are getting more stringent and researchers are working to identify specific contaminants that are on the rise.
In drinking water, an example of an emerging contaminant of concern is chlorate. A byproduct of chlorine degradation, chlorate will likely be regulated in the near future. Chlorate is something that can be addressed by minimizing or eliminating its formation in the first place.
If regulations emerge in the U.S. in the coming years, they will cause significant challenges for communities that use delivered chlorine, also referred to as bulk bleach, since chlorates are formed when the bleach is being stored and waiting to be used. There are currently two primary solutions to the chlorate issue: chlorine gas and electrochemical generation. Chlorine gas doesn’t add chlorates as it is a pure form of chlorine. Electrochemical generation is a safer form of disinfection that can be optimized to control the amount of chlorate production.
Operators and communities are looking to stay ahead of these emerging issues, seeking new solutions and technologies to address current and future guidelines. The good news is that technologies exist — and more are being developed — that:
- Can be selective toward specific contaminants.
- Can not only remove contaminants but also oxidize or destroy them.
- Can be used to drive certain chemical reactions or minimize others.
Finally, operators will need systems that provide immediate and easily accessible monitoring and analytics tools seamlessly integrated into their control systems — truly ‘smart’ water treatment facilities. Putting more real-time data in the hands of operators, allowing them to stay on top of changes and enhance the control of their plants, may lead to increased performance and efficiency and allow them to get more from their plant over a longer life. Efficient, smart systems, combined with new technologies that address emerging contaminants, will put plant operators at a major advantage when keeping pace with our rapidly changing world.
Article originally appeared in Water World: December