title: Nutrient and trace element leaching following mine reclamation with biosolids.
abstract: Mine reclamation with biosolids increases revegetation success but nutrient addition well in excess of vegetation requirements has the potential to increase leaching of NO3 and other biosolids constituents. A 3-yr water quality monitoring study was conducted on a Pennsylvania mine site reclaimed with biosolids applied at the maximum permitted and standard loading rate of 134 Mg ha(-1). Zero-tension lysimeters were installed at 1-m depth 1 yr before reclamation: three in the biosolids application area, one in a control area (no biosolids). Before reclamation, all water samples had pH in the range 4.7 to 6.2, acidity < 20 mg L(-1), and very low levels of all other measured parameters. Following reclamation, percolate water in the biosolids-treated area had lower pH and greater acidity than the control area. Acidity was greatest during the first winter following biosolids application, decreased during the spring, and showed a similar pattern but with much smaller concentrations the second year. Maximum first- year leachate NO3 concentrations were approximately 300 mg L(-1) and half as large the second year. Estimated inorganic N leaching loss during the first 2 yr after biosolids application was 2327 kg N ha(-1). Aluminum, Mn, Cu, Ni, Pb, and Zn followed similar leaching patterns as did acidity, and their mobilization appeared to be the result of the increased acidity. These results indicate that large applications of low-C/N-ratio biosolids could negatively impact area water quality and that biosolids reclamation practices should be modified to reduce this possibility.
authors.affiliation: Crop and Soil Science Department, The Pennsylvania State University, University Park, PA 16802-3504, USA. rcs15@psu.edu
authors.forename: Richard
authors.initials: R
authors.lastname: Stehouwer
authors.forename: Rick L
authors.initials: RL
authors.lastname: Day
authors.forename: Kirsten E
authors.initials: KE
authors.lastname: Macneal
mesh_terms: D004784:Environmental Monitoring; D005308:Fertilizers; D006863:Hydrogen-Ion Concentration; D008906:Mining; D009566:Nitrates / Q000032:analysis / Q000737:chemistry; D009584:Nitrogen / Q000032:analysis*; D010414:Pennsylvania; D010758:Phosphorus / Q000032:analysis*; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000032:analysis / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D013997:Time Factors; D014131:Trace Elements / Q000032:analysis*
chemical_list: D005308:Fertilizers; D009566:Nitrates; D012722:Sewage; D012989:Soil Pollutants; D014131:Trace Elements; D010758:Phosphorus; D009584:Nitrogen