Rule 17.30.630 - TEMPORARY WATER QUALITY STANDARDS(1) Following are the temporary water quality standards and related provisions for New World Mining District:(a) The goal of the state of Montana is to have these waters support the uses listed for waters classified B-1 at ARM 17.30.623(1). The standards for the parameters listed in this rule temporarily modify the specific standards for those parameters provided in ARM 17.30.623 for each of the water bodies listed below, until the temporary standards expire or are terminated by the department. The standards for parameters not listed in this rule are the specific standards listed in ARM 17.30.623. The existing uses of the water bodies listed below must be maintained during the period that these temporary standards are in effect. No increase from existing conditions for any of the parameters that have been temporarily modified (no decrease for pH) is allowed at any point in the affected stream segments. The numerical standards for specific parameters listed below apply only at the downstream end of the stream segment. The requirements of ARM 17.30.623update apply to the waters listed in this rule except where those requirements conflict with the temporary standards listed below.(b) The temporary standards for these stream segments are effective June 4, 1999.(c) Temporary water quality standards for Daisy Creek, from its headwaters to its confluence with the Stillwater River in the Yellowstone River Drainage, are as follows. No increase from existing conditions (no decrease for pH) is allowed at any point in Daisy Creek for any of the following parameters. These standards are in effect until June 4, 2019. Metals standards are in terms of micrograms per liter (µg/liter) total recoverable concentrations and pH standards are in standard units (su). | Parameter | In Daisy Creek at its confluence with the Stillwater River, the following standards shall not be exceeded more than 3% of the time. µg/liter |
| Aluminum | 9,510. |
| Cadmium | 4. |
| Copper | 3,530. |
| Iron | 6,830. |
| Manganese | 1,710. |
| Zinc | 540. |
| pH | must be maintained above 4.6 su. |
(d) Temporary water quality standards for a headwater portion of the Stillwater River, a tributary of the Yellowstone River, from Daisy Creek to the Absaroka-Beartooth wilderness boundary, are as follows. No increase from existing conditions (no decrease for pH) is allowed at any point in this reach of the Stillwater River for any of the following parameters. These standards are in effect until June 4, 2019. Metals standards are in terms of micrograms per liter (µg/liter) total recoverable concentrations and pH standards are in standard units (su). | Parameter | In the Stillwater River at the Absaroka-Beartooth wilderness boundary, the following standards shall not be exceeded more than 3% of the time. µg/liter |
| Aluminum | 670. |
| Copper | 200. |
| Iron | 1,320. |
| Lead | 13. |
| Manganese | 86. |
| Zinc | 49. |
| pH | must be maintained above 5.5 su. |
(e) Temporary water quality standards for Fisher Creek, from its headwaters to its confluence with Lady of the Lake Creek, the headwaters of the Clark's Fork of the Yellowstone River, are as follows. No increase from existing conditions (no decrease for pH) is allowed at any point in Fisher Creek for any of the following parameters. These standards are in effect until June 4, 2019. Metals standards are in terms of micrograms per liter (µg/liter) total recoverable concentrations and pH standards are in standard units (su). | Parameter | In Fisher Creek at its confluence with the Lady of the Lake Creek, the following standards shall not be exceeded more than 3% of the time. µg/liter |
| Aluminum | 470. |
| Copper | 110. |
| Iron | 750. |
| Lead | 2. |
| Manganese | 82. |
| Zinc | 44. |
| pH | must be maintained above 5.7 su. |
Mont. Admin. r. 17.30.630
NEW, 1999 MAR p. 1218, Eff. 6/4/99; AMD, 2000 MAR p. 1317, Eff. 5/26/00; AMD, 2006 MAR p. 3072, Eff. 12/22/06; AMD, 2014 MAR p. 681, Eff. 4/11/14; AMD, 2024 MAR p. 257, Eff. 2/10/2024AUTH: 75-5-201, 75-5-312, MCA; IMP: 75-5-312, MCA