(1) Standard, consistent, and statistically valid field and laboratory methods must be used to obtain and evaluate vegetation data consistent with 82-4-233 and 82-4-235, MCA, and to compare revegetated area data with reference area data and/or with technical standards. Specific field and laboratory methods used and schedules of assessments must be approved by the department for inclusion in the permit. In addition to these and other requirements described in this rule, the department shall supply guidelines regarding representative field and laboratory methods.
(2) Production, cover, and density shall be considered equal to the approved success standard when they are equal to or greater than 90 percent of the standard with 90 percent statistical confidence, using an appropriate (parametric or non-parametric) one-tail test with a 10 percent alpha error.
(3) Areas to be developed for grazing land, pastureland, or cropland must meet or exceed the applicable performance standards in (1) and (2) in any two years after year six of the phase III bond period of responsibility. Pursuant to ARM 17.24.1113, the department shall evaluate the vegetation at the time of the bond release inspection for phase III to confirm the findings of the quantitative data.
(4) Areas to be developed for fish and wildlife habitat, forestry, or recreation must meet or exceed the performance standards in (1) and (2), excluding production, and a minimum tree and shrub density following the requirements of (1). Tree and shrub density must be sampled during the last growing season of the phase III bond period of responsibility. Sampling must demonstrate the following conditions:
(a) all trees and shrubs must be healthy and have been in place for not less than two growing seasons;
(b) at least 80 percent of the trees and shrubs used to determine success shall have been in place for at least the last six years of the phase III bond period of responsibility; and
(c) volunteer and sucker trees and shrubs of the approved species may be included in the accounting for success.
(5) For areas to be developed for residential or industrial/commercial post-mine land use, the vegetative ground cover shall not be less than that required to control erosion within two years after regrading is completed.
(6) The reestablished vegetation must meet the requirements of the Noxious Weed Management Act (7-22-2101 through 7-22-2153, MCA, as amended).