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System (CDPS) No. CO-0043648 for the Cresson Project (Cresson Project Permit). As previously reported to the agencies, the majority of the pumpback that occurred in 2001 was storm water from the highway construction activity azeas. The drought conditions of 2002 introduced another unanticipated variable affecting the amount of flow from the NUD as well as from the south underdrain (SUD}, spring pipe (Sl'}, and Arequa Gulch.Z No flow was observed at Outfa11001A of the Cresson Project Permit throughout 2002. Flows have not been recorded for the NUD since November 15, 2001. Further extension of the VLF that commenced in 2002 is anticipated to continue through 2005 and represents additional changes that make it difficult to evaluate the flow rates and water quality anticipated for the NUD, SUD, SP, and Arequa Gulch. Based on observations to date, it is anticipated that extension of the VLF will reduce precipitation contribution to the ground water system and, thus, flows at NUD, SUD, SP, and Arequa Gulch. As a result of all these factors, the pumpback system has been operated only intermittently since initial installation in May 2001. Review of data collected during the upset conditions of 1998 and 1999 and subsequent monitoring results obtained until flow stopped in 2001 does not provide any defmitive insight on a long term operating plan. Tn fact, the numerous changes that have occurred since 1999 limit the value of any such review. In addition, Paragraph 27 of the Order, as reproduced above, did not pertain only to cyanide excursions associated with the NUD but pertained to managing Arequa Gulch flows to meet all applicable federal and state requirements in the Cresson Project Permit. Until most or all of the above described variables are better understood to allow development of a long-term operational plan, CC&V has adopted an interim approach for operating the pumpback system in a manner intended to meet applicable federal and state requirements, including the terms and conditions specified in the newly issued CDPS No. CO-0043648 for the Cresson Project that became effective on February 1, 2003 (revised Cresson Project Permit). This interim operating plan will be modified as and when information becomes available to define a reasonable relationship between flow and water quality for the NUD, SUD, SP, and Arequa Gulch. Recall that four pipes were approved by the Mined Land Reclamation Board (Board) and were subsequently installed under the VLF as part of initial cons Wction activities and terminate upgadient of Outfall 00] A of the Cresson Project Permit. These pipes are NUD, SUD, SP, and a pipe to be activated at closure to route upgradient storm water under the VLF. The N(JD and SUD collect ground water from the two branches of Arequa Gulch and route the water to where it would naturally flow. The SP collects ground water from a spring system in upper Arequa Gulch and routes the water to where it would naturally flow. The fourth pipe has been decommissioned due to approval by the Boazd in 2000 authorizing expansion of the VLF and routing storm water by channels. 6/6/2003