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2~/~~ ~, ~ EXHIBIT P ~ ~ 5 ~ ~~ ~,g,2 `~ Four horizons have been targeted for mining at Dowe Flats ba`sed'- principally on their cium ~ ,i+~,y .~ ~, carbonate content and utilization potential at Southdown's nearby cement plant. The west limb )l~',~.5''r,9~ J of a southwazd plunging syncline contains the four beds of interest; all outcrop along a general ~'" n.~`s ~ north/south strike and exhibit gentle dips to the east. The Western most seam (also the ~ ~',~' stratigraphically lowest) has been somewhat resistant to erosion and is referred to as the Hi-Ca] o~' ~~ ridge. Expressions of the other horizons are more subdued and these aze known locally as simply y~~ ~ the 2nd, 3rd, and 4th ridges (Map C-2 shows the areal extent of mining for the four ridges wit k ~S p ~ ~~ overlaps due to the stratigraphic superposition of the limestone beds). ~ ,~D~`;~ ~ rim objective of the minin Ian has been to achieve a 25- ear ro'ect life iven the `~"' ~' ~P ~' J BP Y P J ,B ~ ~p expected product mix deriving from the four minable seams and the overall annual tonnage that ~r°-£~ ~~ must be delivered to the cement plant. Currently this annual figure is 760,000 tons, with roughly ~ ~~ tea.. 40% to 45% of this amount contributed each by the Hi-Cal and 3rd ridges. Because the Hi-Cal l~~ t>~ ~ ridge, at its outcrop, dips more steeply than the others, the desire is to maximize mining along P" L,ll `1 its strike length and to avoid excessive down-dip extraction; the objective is to minimize waste ~ ~ ~ handling associated with the removal of the limestone beds. As a result of these factors, it has ~,(,~+~':. been determined that the Hi-Cal bed will need to be mined over a strike length of almost 8,000 ~- w ~ / feet and that the 2nd and 3rd seams will be extracted over a linear distance of 5,000 feet. Only - Q ~, / ti ,900 feet of the 4th ridge outcrop will be disturbed. ~~icr11' ~y' ~z or ~~ fining of each of the respective beds is planned to begin at a southern point along the outcrop, fry' l~ ~'Q with the pit faces advancing towazd the north. Since the limestone will be transported to [he-tY~' w^'_ south for delivery to the plant, the southerly starting location should serve to minimize haulage ~ ~ costs during the early years of operation. '^ ,r e \r a`~ntry into each of the four pits will be from the west; in-pit and mine haulroads are planned withr ~~,~~ a surface width of 60 feet in order to allow safe two-way traffic, and grades will be held to a t ,y~"~~ t maximum of 8%. This latter figure will be significant only on the Hi-Cal ridge wherein the Sk0" N'"~1 outcrop dip attains an inclination of neazly 13%. i ~ ~-~ The initial activity at the site will entail the stripping and stockpiling of topsoil taken from each ~t~ . - V~ of the four starter pits as well as from the planned locations of the permanent out-of-pit waste ,f~.w.lf' storage piles. This will be followed by removal of overburden material from the targeted ~,ha~x , limestone beds and placement of this waste in locations consistent with achieving the post mining ~ ~ contour shown in the reclamation plan. E~,x~°sed limestone will then be extracted and delivered ~`/~ to the nearby plant. ~~~ w'' ~ y~ s~e~! ~ ,,~ ~ a~