2009-10-16_REVISION - M1977036 (8)

Home Browse Search

TETRA TECH Page 5 of 8 Mr. Jared Ebert October 16, 2009 15. On page 3 of the Groundwater Modeling and Mitigation Plan (Attachment G-1), it states that existing ground level measurements were provided from the 14 monitoring wells. This information was not submitted, please submit this information. We have added this information. It is summarized on Table 1 of Attachment G-1. 16. On page 3 of the Groundwater Modeling and Mitigation Plan (Attachment G-1), it states that monitoring will be conducted on a monthly to bi-monthly basis until a quasi steady state is reached and then on a quarterly basis thereafter. Please commit to taking monthly measurements and submitting them in the Annual Reclamation Report submitted by the operator. Once Lafarge believes a steady condition is reached, they will need to submit a Technical Revision to the Division and receive Division approval prior to changing the monitoring schedule from monthly, to bi- monthly and then to quarterly. We have modified Attachment G-1 as requested and made note of the Technical Revision requirement. 17. Please explain what will occur if the two foot drawdown trigger point is observed. The mitigation plan submitted accounts for what will occur if Lafarge receives a complaint but does not address what will occur if the two foot trigger point is reached. The language in Attachment G-1 has been modified to better explain what will happen; please see updated Attachment G-1. 18. If Lafarge receives a complaint from a water user, they will need to notify the Division immediately, not within two weeks. This notice should include a copy of the complaint (if written), a narrative describing how the situation is being evaluated and what temporary mitigation measure they have implemented. Lafarge agrees to notify the Division within 24 hours; we have modified the language in the revised Attachment G-1. 19. On page 4 of the Groundwater Modeling and Mitigation Plan (Attachment G-1), it states "Lafarge has no responsibility to provide mitigation for wells that are constructed after the permit is approved." This is not correct, in accordance with rule 3.1.6 (1) the operator is required to minimize disturbances to the prevailing hydrologic balance of the affected land and of the surrounding area and to the quantity or quality of water in surface and groundwater systems both during and after mining operations and during reclamation. Given this, if the mining and reclamation operation impacts the ability of surrounding land owners to legally use groundwater, Lafarge will be responsible for mitigating these disturbances. Please remove this statement for the Groundwater Modeling and Mitigation Plan (Attachment G-1) and submit a new copy. This statement has been removed from the attached, updated version of Attachment G-1.