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Building on breakthroughs recently made at kraft mills, a survey of mechanical pulp and paper mill effluents was undertaken to gain insights concerning potential effects on fish reproduction. Effluents from seven Canadian mills were characterized chemically for conventional parameters such as biochemical oxygen demand (BOD) and total suspended solids (TSS). Each sample was further subjected to solvent extraction followed by gas chromatographic separation for the determination of resin/fatty acids and for the estimation of a gas chromatography (GC) profile index. Each mill effluent was assessed for the potential to affect fish reproduction in the laboratory using a five day adult fathead minnow (Pimephales promelas) egg production bioassay with exposures to 100% effluent. The seven effluents were found to have substantial variation both in terms of chemical characterization and effects on fish reproduction. Temporal variations were also noted in effluent quality at mills sampled on different occasions. Similar to what has been observed for kraft mills, a general trend of greater reductions in egg production caused by effluents with greater BOD concentrations and GC profile indices was noted. Effluents with BOD > 25 mg/L and GC Profile indices >5.0 caused a complete cessation of egg production. At the same time, about half of the total effluents sampled had BOD < 25 mg/L and GC profile indices <5.0 and caused no significant effects on egg production, suggesting these values may be useful as effluent quality targets for mechanical pulp and paper mills. However, 3 out of 14 effluents sampled had BOD < 25 mg/L and GC profile indices <5.0 and caused significant reductions in egg production. The reason(s) for reproductive effects caused by such effluents is presently unclear. The effluent quality parameters considered in this study may require further refinement to address their utility in predicting the adverse reproductive effects induced by effluents from mechanical pulp and paper mills. [ABSTRACT FROM PUBLISHER]

A great deal of research effort has been undertaken to find an effective solution to the problem of acid mine drainage. Indeed, Canadian legislation requires mining companies to respect environmental regulations by providing a rehabilitation plan with a financial guarantee. In order that the Canadian mining industry remains competitive, the proposed solutions have to be not only efficient but also economic, that is why the use of another waste material is attractive. The main objective of this study was to investigate the technical and environmental feasibility of stabilizing acid mine residues using alkaline paper mill waste produced by the pulp and paper industry as a basic source. The mineralogical characterization of the alkaline paper mill shows that calcite is the dominant mineral with hydrated lime (portlandite) present at a low content. The mineralogical characterization of the mining residues shows a polyphasic system where silica dominates the oxidized zone. On the other hand, a high pyrite content is presentin the non-oxidized zone. The essential observations that emerge from the leaching tests undertaken in the laboratory can be summarized by the efficiency of the incorporation of the alkaline paper mill waste (1/3 waste and 2/3 mining residue) on the production of acid mine drainage. In fact, it can be observed that there is a reduction of thehigh toxicity elements like heavy metals. The increase in pH permitsthe reduction of catalytic bacterial activity and reduces the rate of oxidation in the mining residue. [ABSTRACT FROM AUTHOR]