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5013 . Page 3 $230,000 per year per mg/l for the year 2000. This would amount to $920,000 annual cost from the salinity increase contributed by the FAP. This is far higher than the total of $168,000 reported in the draft statement. The revised figures prepared by the Bureau of Reclamation should be utilized for the final environmental impact statement. Regarding waste water treatment at tunnel construction sites, the draft statement is unclear as to how this water is to be pro- cessed to remove suspended solids. The report states that treat- ment plants will be completed if necessary, but this necessity has already been established during previous construction of similar facilities. In 1972, monitoring operations conducted by the con- tractor at the request of the Bureau of Reclamation and the EPA at the Nast Tunnel site, indicated discharge concentrations in excess of 1,000 mg/l of total suspended solids despite a series of four settling ponds. The State of Colorado and EPA require new source discharge permits to meet the TSS standard of 30'mg/l. From pro- cedures evident during the Nast Tunnel construction, it would appear that a treatment plant utilizing floculation chemicals would be warranted in order to meet this standard. The type of commercial water pollution control device to be used at each tunnel construc- tion site should be described in detail in the final statement. . It is erroneously reported in the draft statement that the contractor is required to limit increases in turbidity to reason- able amounts above natural turbidity. Standards adopted by Colorado Water Quality Control Commission on January 15, 1974 which will be effective on June 19, 1974, limit turbidity increases for streams classified B1, i.e., all of the Frying Pan tributary streams. The proposed standard states that wastes from other than natural origin should not increase the turbidity of the water by more than ten Jackson Units or its equi va 1 ent. ("Water Qua 1 ity Standa rds for Colorado and v Stream Calssification," Colorado Department of Health, Water Quality Con- trol Commission, January 1974) How this standard will be monitored and maintained in order to protect the pristine nature of the streams should be described in the final report. The statement says some tunnel diameters are unnecessarily large in order to accommodate modern tunneling equipment. This can be done at no additional monetary cost according to the report but the environmental costs of this procedure have not been des- cribed. These larger bores will produce larger spoils areas which require larger clearings in the heavily timbered areas which could mean increased erosion~ Additional production of rock fines from this procedure, if any, should be analyzed for the effect upon treat- ment plants and ultimate discharQe. These factors should be con- sidered'when deciding to construct a larger diameter tunnel than needed. . XI-272