In an industry that has such influence over environmental and public health, regulators are a presence. Wastewater treatment plants are required to comply, often both locally and federally, with permits that dictate the amount of constituents that can be present in their effluent. 

But sometimes compliance takes more than just the best efforts of operators. While they may have every intention of meeting their permit requirements, all-too-common errors in the lab, errors with instrumentation, or errors in treatment technology keep them from doing so. Gaining a better sense of the areas where these errors can occur will help treatment operations avoid them in the future and remain compliant.

1. Instrumentation calibration

In essence, calibration is the simple act of applying a given standard to an instrument used for assessing wastewater. A correctly calibrated instrument allows operators to determine their wastewater’s degree of deviation from the standard and make the necessary adjustments to bring that wastewater into regulatory compliance.

It goes without saying that instruments are only useful when they are calibrated correctly. If not calibrated, the tools that treatment plant operators use to take stock of wastewater will provide them with false readings, affecting the way in which they apply chemicals and technology, and ultimately producing mistreated effluent.

Accurate calibration is critical to the entire wastewater treatment process. But, unfortunately, it’s an easy process to get wrong.

Ensuring that plant employees are properly certified and trained to conduct calibration and that they are familiar with a given instrument is paramount to avoiding compliance errors. Properly documenting calibration on the requisite forms and keeping calibration stickers up to date will also help ensure that instruments are providing accurate data.

And not all instruments are built the same. Some are easier to calibrate than others, some require additional equipment to calibrate while others don’t, and some are more likely to lose their calibration over time. Conducting due diligence of the manufacturer’s specifications, the rated tolerance, frequency and degree of difficulty of calibration is a critical way to avoid unnecessary compliance errors wrought by poorly calibrated instruments.

2. Missed measurements

As has been the best practice for years, wastewater treatment plants take stock of their effluent at regularly scheduled intervals. This often involves testing waste streams for key indicators of regulatory compliance — such as dissolved oxygen, pH and nitrate — via manual processes undertaken by operations staff.

But this method may not identify the sudden changes in the quantity of contaminant that can damage the microbes and alter the sludge profile of the treated water and may result in heavy damages to the plant.

To avoid this potential violation, many treatment facilities have turned to real-time monitoring solutions that continuously monitor waste streams and report that data directly to operators. Not only can these tools help plants avoid compliance errors, but they can also significantly reduce the amount of labor required to take measurements and largely remove the potential for human error in the process.

3. Laboratory quality control

No matter how effectively treatment operators utilize their tools, and no matter how closely they monitor waste streams, proper laboratory analysis is a critical step in remaining compliant with regulations.

Despite the importance of properly executed sample grabbing, there are many things that can go wrong with laboratory work. Labs have been known to improperly mark containers, use expired chemicals in analyses, fail to document the dates and times of collections, and to introduce contamination into samples.

To ensure that their methods will yield compliant analyses, wastewater laboratories in the U.S. should conduct their work with U.S. EPA-compliant methods. These can be directly approved by the EPA and published within the Federal Register, accepted versions of previously approved methods that are not necessarily published, equivalent methods that meet or exceed the criteria of EPA-approved ones, or third-party methods that have obtained EPA approval or acceptance.

Though failing to comply with regulations is a nightmare scenario for wastewater treatment operations, it is not unheard of. But many instances of compliance violations can be avoided with a simple effort to reduce common errors.

For more information on instrumentation technologies, visit www.hach.com.