Document pdOY3NomZ7Qz7kpNwoNQmjnj

UNION CARBIOE CORPORATION * MINING & METALS DIVISION P.O: BOX 579 THE DISCOVERY COMPANY NIAGARA FAILS,N.Y. 14302 TEL: 716-285-3311 March 22, 1972 PLAINTIFF'S EXHIBIT UC-4529 Dr, J. U. Crowder Environmental Protection Agency Office of Air Programs Research Triangle Park, N.C. 2771t Dea r Jim: Reprinted below are additional comments from our Engineering Department on the "Control Techniques" document. I reviewed sections 3*2.3 and 4.1 to 4.19 of the draft of "Control Techniques for Asbestos Emissions" with L.C. Kovc, the Engineering Department's Cost Engineer. Eis figures indicate that a standard open belt conveyor, with walkway along one side, vill cost about $2GC/linear foot. Adding hinged belt covers would add about $5-6/iinear foot, depending on belt width. A conveyor in a completely enclosed gallery would cost $325/L.F. The best reference I have seen on tailings stabilization is an article in the "Journal of Soil and Water Conservation'', Vol. 2o, No. 4, July-August, 1971, "Temporary '.find Erosion Control-Cost and Effectiveness of 34 Commercial Materials". The eight materials that were judged effective ranged in cost from $26.90 to $49.50 per acre for material alone, which would be $O.C63 to $0.1l4 per 100 square feet, plus an estimated $71 per acre, $C.lt3 per ICO square feet, for application. The total cost is thus $0,226 to 00.277 par ICO square feet for the coatings mentioned in the article. Note that these gave only temporary protection. We have tried sodium silicate and Coherex on King City tailings and found them ineffective. Actual price comparisons for shaken-bag filters indicate that the exponent (n) ir. the cost vs capacity relationship c2 =. X401626 should be 0.94. This results from the direct relationship of capacity to bag area, and hence to cost. Deferslog to Table 4-3, cur total installed costs are usually 3-5 times the purcha sed cos t of the basic device, and this should be increased to five- times for hi gh oxergy wot scrubbers, since the basic device is relatively simple but the fa slurry handling equipment is the expensive part. These should be d Vi rt *t * * slues, rather than the extremes. " ERA We fee! that the emission factor in Table 5-1 (p. 5-3) for mining and basic processing of "93 Ib/ton of asbestos produced" is ridiculously high but we have no data on which to establish a lower number. This would indicate to a local inspector that we were emitting an average of 9300 pounds of asbestos to the surrounding countryside every day! Very truly yours. /cvb cc: JWR/WN1 NF-FiI X401627