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' Sunmary and Conclusions Colorado MLRD provided Panorama with standards for interpreting the results of overdurden physical and chemical constituents. These were the 'Montana Department of State Lands guideline for suspect levels in overburden material.' Results of overburden sampling and analysts indicate that eight constituents, Including sand and clay, exceed the standards. The suspect constituents are scattered over several overburden sample Intervals: they are not confined to a single strat(graphlc horizon. With the exception of zinc and clay. the constituents marginally exceed the standards. M(xing of the overburden during mining should alleviate environmental Impacts fro^ toxic constituents or unsuitable material (I.e, sand or clay). Design of Test Boring Progran Overview The Rimrock Coal Company permit area is 38 acres, of which, 7.23 acres is designed as Phase 1 Mine area and 6.58 acres is included in a Phase 2 Mine area, Exhibit JJ. • The Englevllle Coal Sea^ within the Vermelo Formation !s the sea^ targeted for mining. The geologic map, Exhlblt K, showa the outcrop and structure of the Englevllle Sean. The overlying. non-coal bearing lower portion of the Raton Fornatlon xlll also be affected by the surface mining operation The practical geologic contact between the Verneio and Raton Formations !s the top of the Soprls Coal Sean, Exhibits FF and GG. The Soprls, with some question of correlation, was penetrated In the exploratory holes. Underlying the Englevllle Sean are a series of thin, uneconomic seams that generally correlate to the Piedmont-Lower Pled~ont seams. Uncertainty e:lsts as to the correct Wane for the bench of coal that underlies the Englevllle Sea^ In many holes. Either Lower Englevllle Bench or Piedmont !s appropriate. In any event, the operation plan !s to leave this thin, lenticular coal in place. Likewise, the plan is to spoil the overlying Soprls Sean and any locally developed seams, unless there thickness and quality xould prove to be econoalcally viable. Location of Sites In consideration of the mine size and original operation plan, . mining In the Phase t area only, samples from Rlnrock hole 29-4 were collected for laboratory analysts. However, the addition of the Phase 2 area, In which stratlgraphlcally higher saterlal will be disturbed, dictated that samples from hole 29-9 be utilized. -5-