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INTRODUCTION On June 30, 1993, representatives of the Office of Surface Mining (Denver and Albuquerque offices), the Division of Minerals and Geology, and Enron Corp. met to discuss certain outstanding issues regarding the 1992 bond release request submitted for the Meeker Area Mines (Permit Number C-81-032). One of the issues discussed at this meeting was the use of the Division's data which was collected as part of the Phase II bond release approval process. This letter will compare the data that was collected by the Division with that collected by the operator. In 1992, both parties quantitatively sampled parts of the reclaimed Meeker Area Mines. The operator's data were collected by Matthew S. Hayes of Hayes Environmental Services (HES) between July 7 and 9 and are summarized as part of the report entitled Meeker Area Mines. Permit Number C-81-032. 1992 Vegetation Report. Phase II Bond Release Request. The Division's data were collected on July 13 and 14 and are described as part of Attachment 4. Narrative Evaluation of Compliance. Although the following discussion was not specifically requested of Enron Corp. as part of the June 30, 1993 meeting, it is included in case any doubt remains regarding how the two sets of data compare. DATA ADEQUACY Page 15 of the Division's Guidelines for Compliance states "The regulations require a demonstration that pre- and post-mine vegetation communities and reference areas have been sampled so as to obtain a statistically valid estimate of the mean for particular parameters such as cover, production and woody plant density. The Snedecor- Cochran sample size adequacy formula is recommended by the Division...." In 1992, the Division sampled only eight points over the entire reclaimed Meeker mine site. The sample adequacy calculation using those eight samples is 13.5, indicating that an adequate sample at the 90$ statistical confidence level was not collected. As demonstrated in Table 4 of the HES vegetation report, the operator's data was collected in excess of adequacy (17 samples collected vs. a sample adequacy calculation of 7.2). Because the Division did not sample the mine site to adequacy, their data cannot be used to refute the operator's data.