Effects of biosolids and compost amendment on chemistry of soils contaminated with copper from mining activities

Abstract

Several million metric tons of mining wastes, called stamp sands, were generated in the Upper Peninsula of Michigan during extensive copper (Cu) mining activities in the past. These materials, containing large amounts of Cu, were discharged into various offshoots of Lake Superior. Due to evidences of Cu toxicity on aquatic organisms, in due course, the materials were dredged and dumped on lake shores, thus converting these areas into vast, fallow lands. Erosion of these Cu-contaminated stamp sands back to the lakes is severely affecting aquatic life. A lack of uniform vegetation cover on stamp sands is facilitating this erosion. Understanding the fact that unless the stamp sands are fertilized to the point of sustaining vegetation growth, the problem with erosion and water quality degradation will continue, amending the stamp sands with locally available biosolids and composts, was considered. The purpose of the reported study was to assess potential effects of such organic fertilizer amendments on soil quality. As the first step of a combined laboratory and greenhouse study, a 2-month-long incubation experiment was performed to investigate the effects of biosolids and compost addition on the soil nutrient profile of stamp sands and organic matter content. Results showed that both biosolids and compost amendments resulted in significant increase in nitrogen and phosphorus concentrations and organic matter contents of stamp sands. Sequential extraction data demonstrated that Cu was mostly present as bound forms in stamp sands, and there was no significant increase in the plant available fraction of Cu because of fertilizer application.

Using Organic Amendments to Restore Soil Physical and Chemical Properties of a Mine Site in Northeastern Oregon, USA

“…This was likely caused by the addition of soluble salts in the biosolids amendments. Sidhu et al (2016) found similar increases in EC from applying biosolids to copper mine tailings at application rates of 2.5%, 5%, 10%, and 20% of the dry weight, where maximum EC occurred in the 20% amendment rate. In contrast, biochar plots had the lowest EC values, which may be a result of adsorption of soluble salts on the charged surface.…”

“…Unlike N, which is mobile in soils, P is less available, remaining in the soil through a wet season (Stevenson, 1986). In previous biosolid application studies, available P remained in the surface soil (0-10 cm; Maguire et al, 2000;Shober et al, 2003;Sidhu et al, 2016). In addition, Maguire et al (2000) found at 11 different test sites of varying application rates, iron and aluminum-bound P was the dominant form of P below 10 cm, which caused decreased plant available-P. Shober et al (2003) found no increase in available P below 10 cm after up to 18 years of annual biosolid application (53.71 Mg/ha).…”

Growing Biofuel Feedstocks in Copper-Contaminated Soils of a Former Superfund Site

“…The added benefit of using oilseed crops would be the production of biodiesel. In an earlier paper, we reported a lab incubation study, where we determined that the addition of compost to stamp sand improved its potential to support plant growth [8]. Our results showed that compost amendment resulted in a significant increase in the nitrogen (N), phosphorus (P), and organic matter (OM) content of stamp sand.…”

Health Risk from Toxic Metals in Wild Rice Grown in Copper Mining-Impacted Sediments

“…In the late 19th and early 20th centuries, the Upper Peninsula of Michigan was a major center for copper mining, generating millions of tons of mine tailings called stamp sands [4]. These metal-rich tailings were discharged into the shores of Lake Superior and other inland lakes in the region, severely impacting the aquatic ecosystem.…”