By Tomas Will, Sr. Environmental Scientist
What types of projects make consultants choose horizontal remediation wells as the best option to achieve their remediation goals? The most typical projects where horizontal remediation wells outperform traditional remediation methods fall into five common categories. Many horizontal remediation projects have characteristics of several of these categories. These categories typify the challenges that consultants can overcome when using the appropriate horizontal remediation methods.
The Inaccessible Contaminant Plume
Oftentimes, site constraints prevent traditional remediation methods from effectively accessing the contaminant plume. Therefore, the success of any remediation process depends on the ability to treat the most heavily contaminated areas of the subsurface. Horizontal wells can overcome access limitations and allow for remediation well systems that are engineered for maximum screen contact with contaminated areas. Typical site constraints include commercial/industrial/residential activity, surface infrastructure, subsurface utilities, sensitive environments, tight interior spaces, and secure areas.
The Bustling Project Site
Traditional remediation methods can frequently lead to temporary site shutdowns that cause lost revenue, schedule delays, loss of resources, and general disruptions to site personnel during the construction phase as well as during long-term O&M. Horizontal remediation wells allow a business-as-usual approach to everyday usage of the project site. Disruptions are eliminated by staging equipment and installing wellheads out of the way of critical areas without sacrificing any remediation system efficiency.
The Ticking Clock
Horizontal remediation wells have a demonstrated ability to achieve cleanup goals in less time than vertical wells by leveraging their ability to pinpoint hot zones and achieve greater amounts of screen contact with the contaminant plume. Faster cleanups and fewer total wells lead to lower O&M costs over the lifespan of a project. Typical reasons for a time-sensitive remediation process include pending property transactions, regulatory pressure, redevelopment plans, and the threat of additional treatment costs from contaminant migration.
The Large Scale Cleanup
Depending on the orientation of the contaminant plume, a single horizontal remediation well can replace and outperform multiple vertical wells. In addition to providing performance benefits, horizontal wells often represent a more cost-effective solution to large numbers of vertical wells. Even on mid-size projects that were initially thought to require as few as 5 vertical wells, horizontal wells have proven to be a budget-friendly alternative.
The High Stakes Project
Many projects are considered high stakes due to human health risks, relations with site occupants and adjacent property owners, ongoing litigation, limited budget for a protracted remediation process, or previous unsuccessful efforts to achieve site closure through a traditional remediation approach. The performance advantages provided by horizontal remediation wells, such as their expanded radius of influence, have often been the final step in achieving site closure, particularly in cases where there was little margin for error.
If your remediation sites have a significant amount in common with these typical horizontal remediation projects, contact Mike Sequino, Principal Engineer, or Tomas Will, Sr. Technical Environmental Scientist, our horizontal well experts, at 877-788-4479 or drilling@directionaltech.com to discuss your current project needs.