HYDRO31322 - Laserfiche WebLink

Home Browse Search

Permit No. CO-0032638 Page 5 appropriate period. The permttee should endeavor [o meet the primary limitations whenever possible. Relief maybe granted for each discharge occurrence only when necessary and shall not be granted when the permiee has control over the discharge. The permittee will need to show that exceedance of the applicable limitations was caused by precipitation and no other source and that the discharge was beyond their control. The Division shall determine the adequacy of proof. As part of this detemrutation, the Division shall evaluate whether the pemuttee could have controlled the discharge in such a manner that primary limitations could have been met. The permttee needs to demonstrate that surface mnoff caused the exceedance of primary limitations. Additionally, the pemuttee shall certify that the pond system was properly designed, operated and maintained prior to and during the dischazge. Manual dewatering of ponds that have no automatic dewatering devices must occur within 48 hours after event end as described in the above pazagraphs to be eligible. All manual dewatering that occurs after 48 hours shall meet settleable solids limitations as applicable. 3. Compliance Schedules All information and written reports required by the following compliance schedules should be directed to the Permits Unit for fmal review unless otherwise stated. a. Sediment Control Plan In accordance with 40 CFR Part 434.82, the permttee must submit aaite-specific Sediment Control Plan to the permitting authority that is designed to prevent an increase in the average annual sediment yield from pre-mined, undisturbed conditions, for Outfalls 004A, and 007A. The Sediment Conhol Plan must be approved by the pemtitting authority and be incorporated into the permit as an effluent limitation. The Sediment Control Plan must identify best management practices (BMPs) and also must describe design specifications, constmction specifications, maintenance schedules, criteria for inspection, as well as expected performance and longevity of the best management practices. Using watershed models, the operator must demonstrate that implementation of [he Sediment Control Plan will result in avernge annual sediment yields that will not be greater than the sediment yield levels from pre-mined, undisturbed conditions. The operator must use the same watershed model that was, or will be, used to acquire the SMCRA pemrit. The operator must design, implement, and maintain BMPs in the manner specified in the Sediment Control Plan. The permiee shall submit the required documentation by December 1, 2007. No later than 14 calendar days following each date identified in the above schedules of compliance, the pemuttee shall submit either a report of progress or, in the case of specific actions being required by identified dates, a written notice of compliance or noncompliance, any remedial actions taken, and the probability of meeting the next scheduled requirement. 4, Chronic WET Testing-Outfall(s): 004A and 007A a. Testing and Reporting Requirements Tests shall be done at the frequency listed in Part LB.I. Test results shall be reported along with the Discharge Monitoring Report (DMR) submitted for the reporting period during which the sample was taken. (i.e., WET testing results for the fast calendar quarter ending March 31 shall be reported with the DMR due Apri128.) The results shall be submitted on the Chronic Toxicity Test report form, available from the Division. Copies of these reports are to be submitted to both the Division and EPA along with the DMR. The pemrittee shall conduct each chronic WET test in general accordance with methods described in Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Or ang isms, EPA/600/4- 89/001 or the most current edition, except as modified by the most current Division guidance document entitled Guidelines for Conducting Whole Effluent Toxicity Tests. The perrnittee shall conduct such tests using Ceriodaphnia dubia and fathead minnows. b. Failure of Test and Division Notification A chronic WET test is failed whenever there is a statistically significant difference ur lethality between the control and any effluent concentration less than or equal to the instream waste concentration (IWC) and when the lethality IC25 is less than the IWC. The IWC for this permit has been determined to be 100% at Outfa11004A and 94% at Outfall 007A. The permttee must provide written notification of the failure of a WET test to the Division, along with a statement as [o whether a Preliminary Toxicity Investigation (PTI)/Toxicity Identification Evaluation (TIE) or