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Mr. ]amet R Stark Cotomda Division ofMimeralr eh'Geohgy Arrgurt 7, 2002 Page 4 ponderosa/pinyon-juniper/meadow environment. The seeding rate has also been adjusted to reduce the PLS/ftz rate to about 41 PLS/ftz. A seeding rate higher than the CDMG recommended rate is proposed to address the probability of reduced gemvnation and survival rates under current prevailing drought conditions (consistent with review and recommendations by David Buckner - ESCO Associates). In addition to the revised seed mix, appropriate permit test pages have been revised and copies of the revised pages aze included with this TR submittal. Comment 17 -Section 2.05.4, page 2.05.4-16, discusser the methods far determining the success of revegetation efforts, bared upon comparironr of vegetative mver, herbaceous production, and woody plant density between reclaimed areas and approved reference areas. The methods ducusred in this section are in compliance with the requiremenu of Rule 4.15.8. On page 4.1 S-SR EFCI refers to areas previously disturbed by mining where the reclamation ruccesr will be evaluated an the basis of effective erosion control and comparisons of resulting ground cover with previously mined areas having similar .rail /raitable material thicknecr and characterrrticr. This discussion of reclamation ruccesr it not consistent with the discussion in Section 2.05.4. The dircrepanry behveen the two discussions for reclamation ruccesr needs to be eliminated The discussion in Secdian 2.05.4 it in compliance with the requirements of rule 4.15.8; the discussion an page 4.15R it not in compliance. Page 4.15-SR should be revised to be consistent with Section 2.05.4. Response; The discussion on page 4.15-SR of revegetation success standazds for previously mined lands reflects consideration of the fact that much of the present surface disturbance azea was previously mined and not reclaimed. Baseline information on historic mining activities presented in Section 2.04.3 (pgs. 2.04.3-1 through 2,04.3-4), and mapping of historic mining and surface disturbance (on Map 12, Mine Area Surface and Groundwater Hydrology, and Map 16, Mine Area Vegetation) document the previous mining disturbance. The provisions of Rule 4.15.10 would seem to provide reasonable relief from normal revegetatioh success standards for previously disturbed areas where limited soil resources and other constraints associated with historic disturbance could limit the effectiveness aad success of revegetation efforts. Discussion of this issue with the CDMG, however, indicates that the CDMG has adopted the interpretation that the provisions of Rule 4.15.10 are not applicable if the identified previously disturbed area(s) has been redisturbed by more recent tnitting and related activities. Given This interpretation, EFCI has developed a weighted average revegetation success standazd for all disturbed azeas within the mine permit area, re Electing pre-mining vegetation types and conditions. The referenced text sections have been reviewed and revised, as appropriate, for consistency and to reflect this modified approach. Copies of the revised pages are included in this TR submittal. Comment 18 -EFCI will compare the revegetation ruccesr an the reclaimed areas to the r Terence areas delineated on Ylap 16. A,r discussed in Rule 4.15.7(4) of the regulations, reference areas can be used in either of two methods for determining revegetation ruccesr, weighted average or individual reference area comparison. The Division i Gufdeliner for compliance with Land Ure and Vegetation Requirements provider a discussion of there options. The narrative an page 4.15-1 and 4.15-SR, under Revegetation Succerr Criteria, implies that EFCI will use the individual reference area comparison by comparing the grassland reference area to the revegetation at the laadout and the refuse pile. It is implied that the Pondemra Pine-Pinyon- juniper woodland reference area will be used to establish standards for the por<al/faalitier area. Please clarify this air Sectionr1.05.4 (page 2.05.4-27, Determination of Revegetatian Succerr), and 4.15.8 of the permit application narrative. Response: After reviewing the referenced text sections, EFCI agrees that the issue of weighted average versus individual reference areas is not cleazly addressed in either Section 2.05.4 or 4.li.8. Further review of Section 2.04.10 makes it fairly clear that, consistent with vegetation mapping and establishment of reference areas, the original intent of the revegetation success evaluation plan was to compaze individual reference azeas to specific reclaimed azeas (i.e.: Refuse Site Reference Area (Plot A -Grassland Type} to the reclaimed Refuse Area; Mine Portal Reference Area (Plot B -Ponderosa Pine-Pinyon Juniper Woodland Type) to the