Laserfiche WebLink
<br />~i <br />COIARADO DEPARTMENT OF HEALTH, Water Quality Control Division <br />Rationale, Page 6 Permit No. CO-0026981 <br />AMENDMENT N0. 1 (Continued): <br />Page lb has been amended to include the revised limitations, and includes the <br />interim limitatlons for lead; page lb (1) has been added to include the final <br />1lmitation for lead. The existing compliance schedule on page lc is still <br />applicable to the revised limitations in Part I. A.2 (page lb) of the permit. <br />A new compliance schedule, which is for compliance with the final lead <br />limitation by January 1, 1941, has been added on page lc(i) of the permit. <br />Page ld has been revised with a new footnote to indicate the monitoring form <br />for metals as either total or total recoverable. Page lj has been added to <br />show the locations of segments 5, 9a, and 9b with respect to the Camp Bird <br />Mine site location. <br />The following paragraph is included in the Statement of Basis, Specific <br />Statutory Authority, and Purpose (Section 3.5.10) of the Classifications and <br />Numeric Standards for the Gunnison and Lower Dolores River Basins: <br />The temporazy modification for mercury for segment 9b, adopted for one <br />year, is based on the level necessary to protect aquatic life. The <br />underlying standard for mercury is based on the level necessary to protect <br />human health, assuming bioaccumulation of mercury in fish tissue. If a <br />bioaccumulation study is completed on this segment by the Camp Bird <br />Venture prior to the expiration of the temporary modification, the <br />Commission will reconsider the appropriateness of the underlying standard. <br />Presently, it is not definite if Camp Bird Venture is planning to conduct a <br />mercury bioaccumulation study. This study is not a requirement of this <br />permit, but will need to be considered with respect to the upcoming Water <br />Quality Control Commission review of the final mercury standard for segment 9b. <br />As of July 31, 1988, changes to the Basic Standards and Methodologies for <br />Surface Water became effective. As part of these changes, the establishment <br />of standards for metals will be based on a hardness-dependent equation. In <br />many cases dissolved standards will be instituted rather than total <br />recoverable. The changes to the new system will be instituted on a case by <br />case basis or as triennial reviews are held. The permittee is advised that <br />this change could result in a change in the limitations for this permit in the <br />future. In addition, the Water Quality Control Commission has determined that <br />in translating these new standards into permit requirements, that limitations <br />will be potentially dissolved rather than dissolved. To facilitate the <br />drafting of a new permit as well as establishing the facility's ability to <br />meet new numbers, it is suggested that the permittee begin monitoring of its <br />effluent and the receiving stream for dissolved and potentially dissolved <br />metals respectively as well as hardness. This data will prove useful in <br />subsequent stream standard hearings as well as in the development of <br />appropriate permit limitations for the next permit renewal. <br />Don Holmer <br />November 29, 1988 <br />