Emerging contaminants are the subject of fervent research and discussion within environmental compliance circles. Emerging contaminants are chemicals that are not currently (or have been only recently) regulated and for which there are concerns regarding their impact on human or ecological health.

Per-(and poly)fluoroalkyl substances (PFAS) are a family of emerging contaminants that have upended our understanding of impacted-site management. Unique challenges of PFAS are related to several factors including their complex chemistry, persistence in the environment, mobility, and toxicology.

What are perfluoroalkyl substances (PFAS) and why are they grabbing headlines? PFAS refers to a class of emerging contaminants that have challenged our understanding of water treatment. PFAS are persistent, highly mobile, and are often released as complex mixtures that may include hundreds to thousands of individual compounds. Furthermore, PFAS are ubiquitous in our society, with widespread use in products such as firefighting foams, stain- and water-resistant textiles, food packaging, and other consumer goods. Production and use of these products, coupled with widespread industrial uses for PFAS-containing materials, have resulted in groundwater and wastewater streams impacted with PFAS.

On June 22, 2020, the Toxic Substances Control Act (TSCA), as reformed by the Frank R. Lautenberg Chemical Safety for the 21st Century Act (LCSA), will celebrate its fourth anniversary. Many of the reformed TSCA framework rules have been drafted and are undergoing implementation, including recent changes to the chemical data reporting (CDR) rule. With the next CDR reporting season beginning soon (June 1, 2020), it is necessary to come up to speed on the reformed TSCA and the updated CDR reporting.

In this session, we will focus on 1,4-dioxane, which, like other emerging contaminants, is currently being evaluated by regulatory agencies for further inclusion in environmental compliance regulations. EPA included 1,4-dioxane in its December 2016 list of top 10 chemicals to be reviewed under the ongoing Toxic Substances Control Act reform.

Data collection is increasingly used to characterize natural source zone depletion (NSZD) to support LNAPL site management. While NSZD is called “MNA for smear zones” by some practitioners, the applicability of NSZD is farther reaching. Natural processes can remove hydrocarbon LNAPL bodies even when active remediation is being conducted, and it is often worth characterizing the processes early in the remedy process.

The collection of high-quality subsurface data at contaminated sites is essential to optimize site management before, during, and after remediation. Withdrawal of soil samples from unconsolidated formation can lead to drainage of pore fluids, volatilization of volatile compounds, and loss of sample from the core barrel. Cryogenic core collection is designed to preserve subsurface conditions and provide a high-resolution data set that can improve conceptual site models, facilitating remediation performance assessment and/or optimization.

Completing Resource Conservation Recovery Act (RCRA) Corrective Action is typically a long and costly process. EPA’s current goal is to have a final remedy constructed at 95% of the RCRA Corrective Action facilities on the Government Performance and Reports Act (GPRA) baseline list by September 30, 2020. Fortunately, EPA realizes that meeting this goal is challenging and has therefore defined a new program (RCRA FIRST) and environmental indicator (CA550 OF) to speed up or reduce costs in RCRA Corrective Action.

Trihydro began developing a UAS program in 2014 to support our mining and reclamation projects, as well as other engineering and environmental projects. After spending nearly a year researching equipment, applications, safety procedures, and applications, we began rolling out our program in the summer of 2015.

Collecting data to support environmental remediation projects can present unique challenges. Remediation sites are often located in areas with limited safe access routes, or where access is limited by environmentally sensitive habitat. Unmanned aerial systems (UAS) provide access and offer an invaluable tool for deploying cameras and scientific sensors to collect the data needed to address unique remediation site problems and challenges. They also replace many time-consuming and high-risk data collection tasks along with providing detail levels previously unattainable because of cost or safety limitation.

Unmanned Aerial Systems (UAS) technology is evolving rapidly and revolutionizing the way environmental industry professionals view their projects. Vegetation analysis was an early application identified for UAS, with the primary focus being the agricultural industry.

Planning for defensible data that may be used in litigation is generally not the first component of a project that we consider for a project sampling or data collection event. However, when the data are in error, data defensibility becomes the most important aspect of the project as the opposing council works to discredit the data. Data quality/defensibility, like safety, should not be left to luck.

Effective data management enables easy data collection, secure storage, and, perhaps most importantly, the ability to retrieve and report that data in a variety of different ways. Unfortunately, data management can mean anything from paper files and Excel spreadsheets, to antiquated legacy systems that do not allow for expansion, access, or sharing of data.

Trihydro provided the engineering design for the first abandoned mine land (AML) project to be completed with Infrastructure Investment and Jobs Act (IIJA) funding.