Administrative Rules of Montana
Department 17 - ENVIRONMENTAL QUALITY
Chapter 17.24 - RECLAMATION
Subchapter 17.24.1 - Rules and Regulations Governing the Montana Hard Rock Mining Reclamation Act
Rule 17.24.187 - SMALL MINER METAL LEACHING SOLVENT OR REAGENT OPERATING PLANS

(a) appropriate maps showing the location of the mine and support facilities, cyanide or other metal leaching solvent or reagent-processing facilities, permit boundaries, and perennial streams;

(b) the average and maximum tonnage/day and per year of ore to be processed and the amount of tailings to be generated;

(c) a narrative description of the precious metal recovery process;

(d) number, size and location of any proposed leach pads and ponds, and ore and tailings piles associated with processing;

(e) leach pad, pond, and waste facility designs;

(f) a plan for a leak detection system, including a program and schedule of monitoring for possible leakage which monitors pH, electrical conductivity (EC), cyanide as weak acid dissociable (WAD), other metal leaching solvents or reagents as appropriate, and other constituent levels, for those constituents appropriate to the type of processing proposed;

(g) a remedial action plan for controlling and mitigating discharges to surface waters;

(h) a description of the amount of make-up water required to operate the plant for ore processing;

(i) a plan for disposal of debris generated by clearing, grubbing and logging ensuring that the debris does not impact water quality or water flow;

(j) sediment and erosion controls for surface disturbances related to cyanide processing facilities;

(k) a road design and construction plan that provides controlled drainage, including location and number of culverts, waterbars, and slash filters;

(l) design for and map of adequate berms for placement around diversion ditches and live streams to prevent water quality degeneration and erosion of disturbed areas;

(m) a plan for stabilization of disturbed stream banks to assure that they will not be left in an erosive condition;

(n) a plan to salvage and stockpile soil from all areas to be disturbed by cyanide processing facilities, including stockpiles and wastepiles;

(o) design and construction plans for diversions and sediment impoundments to pass the ten-year, 24-hour precipitation event. A diversion must be constructed with drop structures, or energy dissipators if necessary to prevent erosion. Diversion ditch berms must be sloped to account for site-specific conditions, including soils, climate, height of structure, and existing natural slopes and must be revegetated, riprapped, or otherwise stabilized to prevent stream sedimentation;

(p) a plan for disposal of liquid and solid wastes which includes identification and application areas and the necessary discharge permits;

(q) end-of-season procedures for shutdown of the cyanide processing facility;

(r) a plan for prevention of damage to or for documentation of any significant historic, cultural, archeological and paleontologic feature within the permit areas on state and federal lands;

(s) identification and preliminary evaluation of reasonably feasible alternative facility sites;

(t) a commitment to comply with the operational requirements of this rule;

(u) a map of monitoring site locations which also identifies well depth;

(v) well logs for those wells identified in (u) above; and

(w) a commitment to avoid perennial streams wherever possible; and

(x) for facilities that are exposed to precipitation flows and that carry cyanidated or other metal leaching solvent or reagent solution, a plan that provides for adequate passage of a 50-year 24-hour storm even flow; and

(y) a plan for preventing wildlife access to facilities with cyanidated or other metal leaching solvent or reagent solutions.