Reclaiming Coarse Taconite Tailing with Municipal Solid Waste Compost

Abstract

Coarse-textured taconite tailing cover about 3,000 ha on Minnesota's Mesabi Iron Range. These tailing are deficient in nutrients, cation-exchange capacity, and moisture-retention capacity and are highly erodible. Previous reclamation efforts, in most cases, have been unable to meet the regulatory requirement for 90% vegetative cover after 3 yr. Small-scale test plots have demonstrated that municipal solid waste compost can be used to successfully reclaim tailing areas, which also provides a use for the compost. There has been a general reluctance to use municipal compost for reclamation activities, however, owing to concerns relating to the release of metals and organics. A field demonstration study was initiated to examine the feasibility of applying the compost on a larger scale and to examine its impacts on water quality and runoff from the reclaimed areas. Three 0.1-ha plots were located on the south-facing slope (15% slope) of a coarse tailing dike. Three treatments were studied: (1) a control with no treatment, (2) standard diammonium phosphate fertilizer application of 448 kg/ha, and (3) a compost treatment with 224 kg/ha fertilizer and 44.8 Mg/ha (dry weight) of municipal solid waste compost. All plots except the control were seeded with a grass-legume mixture and mulched with hay. Runoff collection plots were set up, and lysimeters were installed in each plot. Three months after planting, ground cover was 67%, 39%, and 0% for the compost, standard fertilizer, and control plots, respectively. Biomass, as kilograms per hectare, was 976, 225, and O for the compost, standard fertilizer, and control plots, respectively. Chloride, sulfate, calcium, magnesium, sodium, and nitrate were elevated in the soil water of the compost plot. Nitrate was the only chemical that exceeded water quality standards; however, these concentrations are not expected to significantly impact the local aquifer because the compost is only applied once and the concentrations of all parameters decreased with time.

Waste for wastelands reclaiming taconite tailings basins with organic amendments.

“…The initial studies at USX and EVTAC were small scale (2.5 m x 4 m) plot studies, begun in 1990. The EVTAC study examined the use of peat, yard waste compost, and municipal solid waste compost, while the USX study used only municipal solid waste compost (Norland and Veith, 1995) Plots using paper processing material were begun in 1992 at EVTAC (McCarthy et al, 1994) and a small (0.1 ha) demonstration plot using MSW compost was established at National Steel Pellet Company in 1993 (Melchert et al 1994). In 1997, 2.0 hectare areas of a coarse tailings darn at EVTAC were treated with municipal solid waste compost, municipal biosolids, paper processing material from two different manufacturers and a combination of municipal biosolids and paper processing material.…”

“…Percent cover was measured using a systematic point-quadrat sampling method (Raelson and McKee, 1982) to estimate cover within a 95% statistical confidence. Biomass was estimated by clipping all aboveground plant material from six randomly selected O. l-m 2 quadrats.…”

“…Concentrations of a large suite of organic compounds were measured in the MSW compost; most compounds were not detected (Melchert et al, 1994. No pesticides or PCBs were detected in the MSW compost used in the demonstration project at National, and the only semivolatile compounds detected were butylbenzylphthalate and bis (2-ethylhexyl) phthalate.…”

Mineland Reclamation Using Office Waste Paper De-Inking Residue

“…The U.S. Bureau of Mines (USBM) has established research plots on coarse tailings using organic amendments at several locations in northeastern Minnesota, including Eveleth Mines. The research program of the USBM was established because standard methods of revegetation have not been successful in vegetating coarse taconite tailings (Norland 1993;Norland, Veith, and Dewar 1993;Melchert et al 1994). Many darns and dikes constructed using coarse tailings have only attained a 40 percent to 60 percent plant cover after three years (Shetron and Duffeck 1970;Dewar 1987).…”

Growth and Trace Metal Content of Poplars Planted on Tailing Treated with Municipal Solid Waste Compost

“…The research base necessary for composted MSW to enter markets for environmentally acceptable use on mineland reclamation projects in Minnesota is limited. In a companion study (Melchert et al 1994), MSW compost was applied to a tailing site to examine impacts on water quality and runoff. In recent years other studies have been initiated by the MDNR and the U.S. Bureau of Mines, studying the usefulness of MSW compost as a soil amendment for revegetating coarse !aconite tailing (Norland et al 1991(Norland et al , 1992(Norland et al , 1993.…”