Investigating Emerging Contaminants

As perfluorinated compounds are discovered across the U.S. Air Force enterprise, the service is taking action to address the emerging contaminant at both active and closed installations and meet its mission to protect human health and the environment.. 

  

By Janet K. Anderson, Ph.D., DABT, Billy Claxton and Cornell Long

 


perfluorinated compounds 

Perfluorinated compounds (PFCs) are a family of synthetic chemicals. They are found in nonstick frying pans and fast-food wrappers. They are found in stain-resistant carpet. They are found in an abundance of industrial and commercial items we encounter in our everyday lives.

PFCs also are found in aqueous film forming foam (AFFF), which has been used by both the Department of Defense (DOD) and the private sector to extinguish petroleum fires since 1970. The U.S. Air Force and the U.S. Environmental Protection Agency (EPA) classify PFCs as “emerging contaminants” based on three characteristics: they have reasonably possi­ble pathways to enter the environment; they present a potential unacceptable human health or environmental risk; and they have evolving regulatory standards.

 

AN EMERGING CONCERN

In the late 1990s, EPA began extensive research into the presence of perfluorooc­tane sulfonate (PFOS) in the blood of the general population. The findings led EPA to conduct further research on PFOS as well as similar chemicals in the PFC family, including perfluorooctanoic acid (PFOA).

In January 2009, the agency’s Office of Water issued provisional health advisories for PFOA and PFOS to protect against potential exposure to the chemicals through drinking water. The advisories recommend taking action to reduce human exposure when concentrations for PFOA and PFOS are higher than 0.4-ppb and 0.2-ppb, respectively. EPA also placed PFCs on its Unregulated Contaminant Monitoring Rule 3 List, requiring some public water systems to monitor for these chemicals through 2015. Several states, including New Jersey and Texas, have established state guidelines for PFOA, PFOS and other PFCs.

 

PROACTIVE RESPONSE

There is little established guidance on evaluating human or environmental risk from PFC exposure. EPA has not identified them as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act, nor listed them as regulated waste under the Resource Conservation and Recovery Act.

The Air Force Civil Engineer Center Technical Support Division, to help iden­tify and respond proactively to emerging contaminants and their potential impact on environmental restoration activities, has established the Emerging Issues and Emerging Contaminants (EI/EC) program.

While federal guidance is still evolving, EI/EC specialists are ensuring that the Air Force protects human health and the environment as much as possible, while minimizing the impact on the service’s environmental cleanup program.

 

TARGETED INVESTIGATIONS

Because PFCs are classified as emerging contaminants, it is difficult to determine the exact level of risk they pose to human and environmental health. In turn, it is chal­lenging for the Air Force to gauge the risk these contaminants pose at its installations.

The use of AFFF is the major contributor to PFC contamination at Air Force instal­lations. Air Force firefighters used AFFF beginning in 1970 at fire training sites to extinguish test fires during training activi­ties and at aircraft crash sites. PFOS was the active ingredient of the foam until 2001, when the manufacturer ceased production. Other companies continue to produce non- PFOS containing formulations of AFFF— but these products contain other PFCs.

While the Air Force maintains large stockpiles of the PFOS-containing foam, which is still permitted to fight petroleum fires, in 2010, it established parameters for reducing its existing PFOS-based supply.

Standardized construction of fire training facilities and improved training methods have led to fewer environmental releases of the foam. But such was not always the case. Routine fire training activities typically led to a release of the non-regulated AFFF to the environment.

Because the extent and impact of PFC contamination across the Air Force is largely unknown, the EI/EC Program has conducted research and data gathering through partnerships with industry and academia. It has established interim guid­ance on sampling and response actions at both active and closed installations. In the absence of defined, regulated cleanup standards, AFCEC program managers and BRAC environmental coordinators are conducting environmental sampling at targeted locations. They are focusing on fire training areas, crash sites and areas that contained AFFF fire suppression systems. Locations with a suspected PFC release will undergo groundwater, surface water, soil and sediment sampling to determine whether a release actually occurred. If a release is identified, the site then will be analyzed to ascertain any potential risk to human health and whether the contamina­tion has migrated off the installation.


Because the extent and impact of PFC contamination across the Air Force is largely unknown, the EI/EC Program has conducted research and data gathering through partnerships with industry and academia.


 

REMEDIATION OPTIONS

There currently is limited experience in remediating PFCs. The most effec­tive method has been pump-and-treat technology—using carbon filters to strip contaminants from extracted groundwater before returning it for reuse. While this treatment can be effective, it also can be costly in terms of energy use and replacement and disposal of carbon filters.

The Air Force and DOD, in a concerted effort to find more envi­ronmentally friendly and efficient forms of treatment, are spearhead­ing a search for alternative reme­diation technologies through DOD’s Strategic Environmental Research and Development Program and AFCEC’s Broad Agency Announcement Program. Approaches being tested include bioremediation, advanced and enzymatic oxidation, and sonoloysis.

Early results are mixed since PFCs are incredibly stable and resistant to transformation. Despite this, research­ers persist in trying to crack the code to degrade these compounds into less harmful forms.

 

STUDYING SOLUTIONS

In 2012, following the detection of elevated PFC levels from local fish tissue samples at Clark’s Marsh, south of the former Wurtsmith AFB in Michigan, the Michigan Department of Community Health issued a “Do Not Eat” fish advisory for certain fish species in the area. The Air Force began a base-wide investigation to determine the extent of PFOS and PFOA contamination. PFC presence near Clark’s Marsh is believed to be the result of AFFF use at Wurtsmith’s former fire training site.

After researching the nature and extent of contamination, AFCEC, in conjunc­tion with federal and state regulators and local leadership, conducted a study and concluded that “pump and treat” was the most effective mitigation system to address the PFCs in surface water. Construction began in October 2014 and AFCEC antici­pates the system will be operational early in 2015. It will treat groundwater upstream of Clark’s Marsh at a rate of 245-gal/min.

In May 2014, the city of Portsmouth, N.H., shut down Haven Well, a public drinking water well on the former Pease AFB when it discovered PFC levels above provisional health advisory levels. Since then, AFCEC has conducted bi-weekly sampling of four public drinking water wells, and tested 30 private wells near Pease for PFCs. One private well showed a concentration above EPA provisional health advisory levels and steps were taken to ensure the homeowner had continued access to safe drinking water.

The restoration team at Joint Base Cape Cod, Mass., has taken a proactive stance in addressing PFCs associated with former fire training activities at the Ashumet Valley plume. In summer 2014, monitor well sampling revealed PFCs at levels slightly above EPA provisional health advisories at some locations. The Air Force sampled off-base wells and a few private drinking water wells. All results were either non-detect, or at extremely low levels, indicating no risk to human health.


 In 2012, following the detection of elevated PFC levels from local fish tissue samples at Clark’s Marsh, south of the former Wurtsmith AFB in Michigan, the Michigan Department of Community Health issued a “Do Not Eat” fish advisory for certain fish species in the area. 


 

THE PATH FORWARD

AFCEC experts continue to raise aware­ness of PFCs and current Air Force and DOD guidance on emerging contaminants by hosting training courses and events, providing up-to-date reference materials for project managers and BRAC environmental coordinators, attending and conducting technical presentations at restoration advi­sory boards and regulator meetings, and participating in industry outreach events.

Through the proactive approach of its EI/ EC Program and environmental restoration teams, the Air Force is committed to its mission to protect human health and the environment.

The Air Force will continue to work with federal, state and local regulators to identify potential risks and established guidance for addressing PFCs in communities surround­ing both active and closed installations.

 


 

Janet K. Anderson, Ph.D., DABT, is Emerging Issues/ Emerging Contaminants Program Manager, and Cornell Long is Chemistry Subject Matter Expert, Air Force Civil Engineer Center Technical Support Division. They can be reached at 210-395-8438, or This email address is being protected from spambots. You need JavaScript enabled to view it.; and 210-395-8436, or This email address is being protected from spambots. You need JavaScript enabled to view it., respectively.

Billy Claxton is Program Manager, Air Force Civil Engineer Center BRAC Program Management Division; 210-395- 9475, or This email address is being protected from spambots. You need JavaScript enabled to view it..