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Mathews Page 2 July 26, 1999 PHC predictions contained in the permit document predict minimal surface flow losses in Rapid and Cottonwood Creeks. This prediction cannot be verified if the upstream monitoring is eliminated. An upstream monitoring site is necessary to demonstrate that the mine operation is not impacting water quantity. I do not think it would be warranted at this time to entirely remove the upstream monitoring points for Cottonwood and Rapid Creeks. Because SWGS 02 and SWGS OS both provide monitoring on Cottonwood Creek upstream of the underground workings, one of these locations could be eliminated from the approved monitoring plan. At least one upstream monitoring location on Cottonwood Creek and SWGS 03 on Rapid Creek should remain as part of the surface monitoring program. No data were presented by the operator to substantiate the claim [hat surface flows in these creeks consist entirely of flows released from upstream reservoirs. Regardless of the source of flow, the Division still requires monitoring of surface water drainage into the permit area. It was also noted that the majority of required monitoring data for sites SWGS 02, SWGS 03, and SWGS OS were missing from the 1998 Annual Hydrology Report. This lack of data makes it difficult to make a current assessment of the utility of these sites as monitoring points. Further study may warrant a permanent reduction in the surface monitoring plan for Cottonwood and Rapid Creeks. However, at this time the only reduction that would be advisable is removal of one of the two sites located on Cottonwood Creek (either SWGS 02 or SWGS OS). Ideally, the remaining monitoring point should be located outside of the angle of draw of subsidence associated with the mine workings. In April, 1999, I inspected the Roadside Mine with John Walters present. We inspected both Jerry and Coal Creeks and discussed monitoring considerations for both upper and lower stations on each creek. Based on the site visit and further discussions within the Division, it was determined that monitoring could be discontinued at the upstream locations SWGS 07 and SWGS 09. This decision was based primarily on the ephemeral nature of these creeks and the difficulty in monitoring these sites. Previous monitoring indicates that these creeks only flow for a short duration in response to storm events, which provides limited data. Furthermore, establishing a reliable measurement technique has been very difficult and access to these sites is poor. I inspected the proposed lower monitoring point on Coal Creek during the site visit. The culverts located between the two refuse disposal areas appear to be a good location for the lower monitoring point on Coal Creek. A Flow rating chart was provided for the Coal Creek culverts. A flow rating chart or other suitable means for determining flow in the culvert used for the lower Jerry Creek monitoring point should also be submitted to the Division. Please let me know if you have any questions or require additional information. Larry Routten