New 6NYCRR Part 363 Landfill Regulations Include Emerging Contaminants

Author: Marc W. Sanford, P.G.

The recently adopted revisions to the Part 360 solid waste management facilities regulations now include requirements for monitoring per- and polyfluoralkyl substances (PFAS) and 1,4-Dioxane as part of the facility environmental monitoring plan.  These emerging contaminants are included as organic parameters under Table 3B of the Expanded parameters list.  The most notable PFAS compounds, PFOA and PFOS, have been linked to the manufacture of certain heat, stain and water resistant products and other sources such as aqueous film forming agents (AFFF), a component of fire-fighting foams. 1,4-Dioxane is used in paint strippers, waxes, dyes, varnishes, and as a stabilizer for chlorinated solvents. 

Past studies in the U.S. and recent investigation of landfill sites in New York and Vermont have shown that PFAS compounds are present in municipal solid waste leachate with PFOA and PFOS present in leachate at concentrations in the part per trillion range or higher.  For some closed, unlined landfills, this has resulted in groundwater contamination by PFOA and PFOS above the USEPA health advisory of 70 parts per trillion.  Currently, the NYSDEC/NYSDOH have been requiring analysis of PFOA and PFOS using USEPA Method 537 Modified with laboratory analytical detection limits as low as 2 parts per trillion. Given these low concentrations driving potential health concerns and detection monitoring of PFAS compounds, it is imperative that existing environmental monitoring programs and sampling methodologies be carefully reviewed and updated to prevent potential false positive detections as a result of contamination from PFAS containing sampling equipment, PPE and materials, or other substances that can cause interference with the PFAS analysis. 

The rollout of the additional PFAS and 1,4 Dioxane monitoring requirements will be triggered by issuance of a new permit or permit renewal.  Although not specified in the revised regulation, the requirements for sampling of PFAS and 1,4-Dioxane will likely vary for new and existing facilities.  For operating landfills, the expanded parameters are typically only part of the leachate quality monitoring program.  Environmental Monitoring Plans for affected facilities will require modification to address the necessary changes in sampling methodology and analytical testing protocols.  

We can expect further assessment and evaluation of these emerging contaminants as data is generated from future investigation/monitoring of PFAS at landfills (and at contaminated sites under various other regulatory programs), and as the newly launched studies on PFAS by the Center for Disease Control and New York’s new Drinking Water Council pursue regulations for these chemicals. In the interim, NYSDEC has recently initiated their own sampling at operating landfills to determine the presence of PFAS and 1,4 Dioxane.