Identification and remediation depend on a combination of proven processes and awareness of the latest advances.
If there’s one thing businesses and markets dislike, it’s uncertainty. That’s why the concept of emerging contaminants can be a little unsettling. But this is a challenge that usually can be addressed and mitigated with the right care, attention and planning.
Emerging contaminants are chemicals or suites of compounds that are gaining closer attention from the environmental community over concerns or new information about their potential toxicity and
adverse effects to human health and the environment. Their presence in soil or groundwater is drawing attention from potentially affected communities.
“These are compounds that haven’t historically been focused on from an environmental perspective, but are becoming a driver of environmental projects due to a better understanding of their potential effects on health and the environment,” says Brian Hoye, a project manager at Burns & McDonnell.
“As practitioners, we are working to understand more about the nature of these contaminants and their behavior,” Hoye says. “There’s less certainty about how we address them because they are new and emerging, and we might not have as many proven approaches to utilize like we do when addressing more traditional contaminants.”
Similarly, sometimes newer analytical methods can accurately detect and assess their presence at lower concentrations, showing that emerging contaminants are more prevalent than was previously thought.
Standards Take Time and Study
As awareness grows, governmental agencies conduct studies and issue advisories or limits. At the federal level, the U.S. Environmental Protection Agency (EPA) generally leads the way with research and risk assessments. The EPA maintains a list of emerging contaminants in drinking water that might warrant further study and regulation. The EPA issues a shortlist of up to 30 unregulated contaminants for which the public water systems must be monitored. Based on the results of this monitoring, the EPA decides which contaminants will be added to the list for possible new drinking water standards.
“Bigger picture, the EPA is conducting more studies and analysis,” says Raghu Arora, an environmental project manager at Burns & McDonnell, citing the emerging example of per- and polyfluoroalkyl substances (PFAS). “Once it comes to a point where they’re certain they have collected and analyzed the scientific data, then they’ll come up with an enforceable standard, and that takes time. Until then, the EPA has issued health advisories with provisional standards.”
But the absence of a standard doesn’t mean a potential problem isn’t lurking.
The challenge for businesses is that these health advisory recommendations might not agree; some regulatory agencies could take a more stringent approach than others. And until the ecological risks and risk to human health from a contaminant are understood and regulatory standards established, no immediate action is required, although companies can be proactive and start addressing the issues now by identifying and remedying known threats.
Emerging Contaminants in the Spotlight Now
There is much discussion within the industry about 1,4-dioxane (a solvent used in some chemical manufacturing) and PFAS (a suite of compounds that have been used for their nonstick and water-repelling attributes, as well as their use in fighting fires). Pharmaceuticals in drinking water, such as endocrine disruptors and growth hormones, also are getting increased attention.
“Many of the pharmaceuticals and PFAS are of interest because our water treatment systems weren’t developed to remove these compounds,” says Hoye, who leads the company’s PFAS technical working group. “As a result, they’re potentially making it through water treatment systems and into drinking water supplies.”
These chemicals have the potential to affect a wide range of industries, including those that make and utilize the compounds and those that use materials which contain those compounds.
Companies whose processes involve products containing PFAS should ask, “How much do we handle products containing these compounds, and do we have potential to modify our procedures to move away from those materials? If so, what is the cost implication associated with that transition versus the reduction in potential risks associated with either contributing to an ongoing source to the environment or potentially having a future release?” Hoye says. “And if they can’t get away from those materials, what precautions need to be taken in how these materials are handled so companies can better protect themselves from releasing them to the environment?”
Defining the Problem Sets a Path to Solutions
Being prepared to address emerging contaminants means being informed of developments that address them. That includes keeping up to date on ongoing research and development of environmental site investigation standard operational procedures, as well as developing cost-effective remediation technologies.
“We bring our engineering and scientific knowledge to bear to make sure we understand the current and future implications of emerging contaminants, and we work in conjunction with the scientific world to address these issues,” Arora says. “For emerging contaminants, treatment is coming from universities and research labs. We’ve been in contact with several universities, collaborating with them to understand what they’re working on and the latest technologies out there that we could use to treat and minimize liability for our clients.”
Hoye says one of the first steps a concerned industry can take when approaching emerging contaminants is to perform an inventory of its products and processes. A better understanding of processes as they relate to a given emerging contaminant helps identify an approach to investigation and remediation.
“First you understand how big your problem is,” Arora says, “then you attack it, break it into pieces and go through the process. So what is the ideal way of treating it, what is the most cost-effective way? We can analyze it, define your problem, then figure out how to treat it by utilizing sound engineering practices coupled with proven technologies and innovative solutions.”
In the absence of mandated limits or a regulatory standard, some choose to wait as the risk assessment and regulatory processes play out and competing recommendations are aligned. Others prefer a proactive approach to understand the extent of the issue or potential contamination plume, which can factor into the potential treatment options.
Sometimes existing investigation and cleanup techniques can be applied to emerging contaminants, but not always.
“For emerging contaminants, it can be a new frontier, a new approach, and a new set of challenges for investigation and remediation,” Hoye says.
A Sampling of Emerging Contaminants
- 1,2,3-Trichloropropane (TCP)
- 2,4,6-Trinitrotoluene (TNT)
- Dinitrotoluene (DNT)
- Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)
- N-Nitroso-dimethylamine (NDMA)
- Methyl tertiary butyl ether (MTBE)
- Polybrominated diphenyl ethers (PBDEs) and Polybrominated biphenyls (PBBs)
- Pharmaceuticals, personal care products (PCPs), and endocrine disrupting compounds (EDCs)
Note: This list provides general information only. It is not all-encompassing and is subject to change.
The PFAS Progression
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were first manufactured in the 1950s as effective fire suppression agents. Prized for their fire-, water- and oil-resistant and nonstick properties, these compounds became widely used in a variety of commercial and consumer products.
Industry has moved away from certain PFAS compounds, namely PFOA and PFOS, over concerns that they are harmful to human health, replacing them with what are believed to be less toxic PFAS compounds and, when possible, PFAS-free substitutes. U.S. manufacturers began phasing PFOA, PFOS and their related compounds out of production in the early 2000s in response
to new EPA regulations regarding the continued use of these compounds.
The environmental community has continued to study these compounds to better understand their health effects and physical properties. Recent information regarding the toxicity and potential for these compounds to accumulate within humans resulted in 2016 EPA health advisories, establishing a limit of 70 parts per trillion for the combined concentration of PFOA and PFOS in drinking water.