From The Editor | April 10, 2017

Established Routine: How To Sample For Unknown Contaminants

Peter Chawaga - editor

By Peter Chawaga

To enable utilities, laboratories, and emergency responders responsible for protecting drinking water, the U.S. EPA has updated its “Sampling Guidance for Unknown Contaminants in Drinking Water.” The guide outlines procedures for water monitoring and sampling after potential contamination, providing the first steps toward remediation.

As the nation’s foremost regulatory body for drinking water, the EPA knows that a most crucial process in stemming contamination problems is proper sampling and getting those samples to analyzers in the right way.

“The sampling guidance allows utilities to consider information that can assist their samples when collecting, storing, preserving, and transporting samples so that they can be analyzed effectively by labs,” an EPA spokesperson said. “It is important that samplers properly collect and handle samples in order to increase the chance that the labs are able to detect contaminants that may be present.”

While the guidance document was originally released in 2008, this year’s update was an effort to incorporate feedback the EPA has received from laboratories, as well as other federal and state agencies. To draft the guide, the agency relied on its “Drinking Water and Wastewater Response Protocol,” its source of best practices for site characterization and sampling.

To help prepare for a potential emergency, the EPA encourages utilities to familiarize themselves with the document and use its contents to supplement response plans.

“They can prepare and store sampling and field test kits ahead of time, and ensure they have sufficiently trained staff to conduct sampling activities,” said the spokesperson. “Utilities should also establish relationships with their receiving laboratories and other response partners before an emergency occurs.”

In fact, for utilities that are worried about unknown contaminant inundation following emergencies, a best way to prepare is to incorporate proper sampling protocols before something catastrophic ever happens.

“This guide is most effective when used prior to an emergency, to increase proficiency with sampling procedures,” the spokesperson said.

But the guidance should not only be accessed when a utility has reason to believe an unknown contaminant has made its way into source water, whether that be due to an upstream chemical spill, flood, or some other catastrophic event. Proper sampling and transportation techniques are important parts of everyday testing.

“Utilities should also conduct routine sampling and baseline monitoring to establish a profile of what substances are in their water system and at what concentrations under normal operating conditions,” said the spokesperson. “This information can help to determine whether a contamination incident has occurred.”

An accurate baseline will be one of the handiest tools that a utility can have when disaster strikes.

“Baseline monitoring can help utilities determine if and how much of the contaminant was in the water before the incident occurred to help determine a remediation clearance goal,” the spokesperson said. “Sampling can help to determine whether the decontamination efforts have been successful at reducing the concentration of the contaminant in the system to the established clearance level, or whether any secondary contamination may have occurred.”

It may not be as dramatic of a reaction as emergencies tend to call for, but the ability to overcome contamination events starts with the establishment of proper sampling routines. With those in place, utilities, laboratories, and emergency responders will be empowered to protect consumers against catastrophe.