Groundwater Monitoring & Remediation has issued a call for papers for a special issue focusing on sites currently being treated in whole or in part by natural attenuation.
Natural attenuation (NA) became a well-used term in the 1990s as groundwater professionals became aware that polluted aquifers were often difficult and expensive to restore by pumping and treating the water, or even by establishing some in situ alternatives. Juxtapose these difficulties next to the growing awareness that the subsurface has a remarkable capability to attenuate pollutants, sometimes by transformation to harmless products and sometimes by sequestration and the potential for
harnessing natural attenuation was undeniable.
Arguments that NA was a strategy for side-stepping site cleanup costs eventually yielded to research and experience that validated the effectiveness of the approach, both from a better understood mechanistic viewpoint and data-driven, on-site experiences.
To ensure that the expected effectiveness is realized, NA is usually accompanied by a monitoring program, hence the more recent moniker “Monitored Natural Attenuation” (MNA). The modern relevance of MNA was summarized by Newell et
al. (2021):
“MNA is now considered one of several remedial technologies that can be employed at contaminated sites, as long as the science behind natural attenuation (NA) processes is well understood and MNA helps manage the chemicals of concern (COCs) in groundwater … There is an extensive collection of MNA protocols and guidance for implementing MNA for a wide variety of COCs in groundwater … Depending on site conditions, MNA can be applied in several different ways: (1) to manage an entire plume with or without source remediation; (2) to manage a portion of the plume, based on horizontal/vertical location and contaminant type; (3) as a polishing step after plume remediation.”
As alluded to above, MNA is not simply a site left to its own devices. Sites must be monitored with physical tools including conventional wells, multilevel wells, geophysical tools, sensors, and aerial surveys; the ensuing data is interpreted with
models and statistics; sites may undergo MNA in addition to other more active remedial actions with care taken to prevent interferences; MNA must be negotiated with regulators and other stakeholders, including local communities; MNA may lead to site
closure; MNA is not foolproof and may not achieve its desired end goals, necessitating new activities to achieve site closures.
This special issue of GWMR invites researchers and practitioners to submit papers relating these and other experiences that will bring the readership up to date with the state of MNA in contaminant hydrogeology.
Topics of interest include but are not limited to the following:
- Case studies involving MNA as the sole method of restoration
- Case studies involving MNA used in conjunction with other methods
- Case studies involving interactions between professionals, regulators and communities
- MNA performance leading to, or projected to achieve, site closures
- MNA evaluation by physical methods of monitoring, using chemical, geophysical, sensor arrays, or remote sensing technologies
- MNA modeling and data analysis
- Extending MNA with abiotic processes of attenuation
- Explaining MNA failures
GWMR is currently targeting publication of this focus issue for publication in the fall of 2025.
Please send a brief synopsis of your proposed manuscript by Dec. 1, 2024, to jfdgwmr@ku.edu. Drafts for review are due by February 27, 2025. All manuscript submissions will be subject to the
normal GWMR peer review process.