"This project was initiated to provide an evaluation of the effectiveness of existing treatment technology for upgrading steel mill wastewaters to Best Available Technology (BAT) Economically Achievable limits for Blast Furnace Category scrubber wastewaters. The wastewater tested was a blast furnace effluent from an operating steel mill treatment system that met 1977 Effluent Guidelines for Best Practical Control Technology (BPT) Currently Available. This wastewater contained residual concentrations of suspended solids, BOD, oils and greases, phenols, cyanides, fluorides, ammonia compounds, sulfides, and dissolved solids. The in-depth pilot plant study was performed using mobile facilities designed especially for treating steel plant wastes. Treatment processes evaluated during the study included: alkaline chlorination, chemical treatment, dual media filtration, magnetic filtration, reverse osmosis, ozonation and activated carbon. Based on the performance results of the pilot program, it was concluded that the physical/chemical technology investigated (alkaline chlorination, ozonation, and reverse osmosis) was effective in reducing influent blast furnace scrubber wastewater contaminants to below BAT levels. Evaluation and comparison of the treatment train capital and operating costs determine that alkaline chlorination was the least-cost alternative. The study also concluded that significantly less space was required for the treatment train utilizing ozonation than for treatment trains involving alkaline chlorination or reverse osmosis."