Ken Goldstein, CGWP, will moderate a session titled “High-Resolution Characterization in Fractured Rock” at the upcoming 2017 NGWA Conference on Fractured Rock and Groundwater, October 2-3 in Burlington, Vermont.
Goldstein is senior vice president, water and environmental systems at Louis Berger. He recently shared his insights with us on fractured rock characterization and what he is looking forward to learning at the conference.
NGWA: How will this conference foster the development of new technologies in fractured rock?
Goldstein: This conference attracts top practitioners in fractured rock hydrogeology from academia, private industry, consulting engineering companies, and regulators. This diverse group brings to this forum many demonstrated applications of proven and developing technologies, which, through numerous high-quality presentations and open dialogue, creates an exchange of ideas and, sometimes, paradigm shifts, leading to the potential development of new technologies and/or refining existing technologies to address the needs of the industry.
NGWA: What will be presented at this conference that will improve site characterization and remediation plans?
Goldstein: Better site characterization leads to higher quality and quantity of critical information used to define the site conceptual site model (CSM). When we have a high degree of confidence in the CSM, we will make better decisions on the remedial approach for a particular site.
At this conference, we will learn about new and/or refined high-resolution sampling techniques such as the quantification of matrix diffusion of contaminants and the role that the matrix diffusion plays in contaminant transport, plume attenuation, and successful remediation approaches, including the demonstration of successful remediation in fractured rock. We will learn about advances in depth discrete sampling and continuous profiling techniques to define the distribution of dissolved-phase contaminants in the fracture controlled hydraulic systems. When we have a better understanding of the dynamic between matrix diffusion and fracture-controlled flow we will have developed better remediation plans and ways to demonstrate successful remediation.
NGWA: You’re scheduled to moderate the session on “High-Resolution Characterization in Fractured Rock.” What are you hoping the attendees learn from the session? And what are you hoping to learn from it?
Goldstein: First, I am hoping that attendees get the major takeaway, which is the importance of incorporating high-resolution sampling (HRS) of the rock matrix and the fracture hydraulic flow network into site characterization and/or remediation performance plans. As high-resolution sampling can be costly, a balance needs to be established between the amount of HRS data needed, the level of uncertainty that can be tolerated in the CSM/remedial plan, and the ultimate costs.
Often, making the expenditure on HRS in the upfront phase of a site remediation project will lead to a more successful and cost-effective remedial strategy/remediation. I am hoping to learn about the advances in the state-of-the-science in high-resolution sampling and how HRS is better informing remedial decision making.
NGWA: What are the main types of fractured rock problems and challenges that you see in the future?
Goldstein: I think that one of the major challenges that fractured rock sites pose is our ability to predict how a fractured rock site is going to respond to various remediation approaches and strategies. This translates into our ability to perform predictive modeling, at a high degree of certainty, of the fracture-controlled hydraulic system, contaminant transport and attenuation processes, and response to remedial measures.
Even when we think we have a site well characterized, we are often surprised by our ability to deliver and distribute various reagents or influence contaminants in the way we anticipated. Another challenge will be our ability to demonstrate and convince the public that sometimes it may not be pragmatic to try and actively remediate a fractured rock site. What lines of evidence will need to be developed, how much HRS data will be needed, and what level of uncertainty can we live with?