Northern Prairie Wildlife Research Center
Land Reclamation Research Center, North Dakota State University, P.O. Box 459, Mandan, ND 58554; North Dakota State University, Department of Soil Science, Walster Hall, P.O. Box 5638, Fargo, ND 58105
Mitigation for loss or degradation of prairie potholes and other wetlands in the surface coal minelands of semi-arid western North Dakota has historically focused on the development of hydric soils and hydrophytic vegetation rather than recreation of pre-mining hydrology. Thus, although mitigated areas may initially "look" good, they may not be viable over the long term. Instead, the extent of both the wetland proper and its watershed must be viewed in terms of the ground-water recharge potential of the site.
Infiltration and soil-water distribution in the root zones of minelands from post-SCRMA (Surface Mining Control and Reclamation Act of 1977) reclaimed landscapes in western North Dakota have been found to be practically zero. This can be attributed to low precipitation, rolling topography, and low hydraulic conductivity of layered and compacted subsoil and spoil materials in the soil profile. Thus, as the percentage of post-mining area increases in a region, the annual amount of recharge to ground-water decreases. Continued ground-water withdrawal in such areas exacerbates the probability of contamination and shortage of the ground-water resource. A solution may be to set aside large areas for ground-water recharge purposes. Properly designed wetlands can provide for ground-water recharge and develop habitat for fish and wildlife resources.
Research on the hydrology of wetlands in post-mine areas of western North Dakota began in 1992. The goal of this work is to quantify comparative hydrology and ground-water recharge potential of natural wetlands, those created with post-SCRMA guidelines, and inadvertently created wetlands on abandoned mine sites. Results should provide the information needed to effectively design wetlands for post-mine sites that will be cost effective and hydro-ecologically viable.