2011-05-23_REVISION - C1981019 (2)

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Colowyo Response - PR3 adequacy No. 2 16 May 6, 2011 communities with 2 sub-types (mesic and xeric). Please breakdown the seed mix to explain which species are appropriate for each of the various reclaimed vegetation types, and provide evidence of other reclamation projects where a single seed mix met all the revegetation standards required by the Colorado Mined Land Reclamation Board across many vegetation communities. Colowyo's Response: CDOW is supportive of Colowyo's approach with respect to the seed mix provided for areas targeted for grassland establishment. CDOW is also supportive of the concept that microhabitats will be created due to differential establishment success of individual species within the mix due to differences in annual precipitation patterns, aspect, slope steepness, topsoil depth, and changes in elevation as reclamation progresses. CDOW's February 15, 2011 letter to CDRMS specifically supports Colowyo 's use of the sagebrush steppe mix and grassland mix with the exception of the addition of Utah sweetvetch (which has subsequently been added to both mixes). Furthermore, there are many examples around the Western U.S. where differential dominance by the species in a mix take advantage of site-specific circumstances and various niches created in the post-mine environment. Also, attempting to replace each pre-mining community with a specific seed mix is a "restoration " procedure, not a "reclamation " procedure, and reclamation, by definition is attempting to replace the foundations of a future successful ecosystem. 5. The seed mix tables 2.05-7,-8 & -9 in Volume 1 are difficult to read due to the small font size. Please re-submit these and other proposed seed mix charts with a larger font size. CCC provided legible seed mix tables. This item is acceptable. 6. Please add text stating that the seeding rate of the drilled species will be doubled in the areas which are inaccessible by the drill seeder and that these species will be exclusively broadcast seeded in the areas inaccessible by the drill seeder. The Division is not familiar with the relationship between increased broadcast seeding rates and lower plant diversity. Doubling the seeding rate for broadcast seeding to that of drill seeding is to account for loss of seeds to predation, desiccation and wind and water erosion. Please provide evidence, such as peer reviewed articles/studies, that demonstrates a relationship between increased broadcast seeding rates and an increase in competitive grass species thereby decreasing community diversity. Note: the proposed seed mix listed in Table 2.05-7 for Collom has a very high grass component and low shrub/forb diversity. Rather than lowering the seeding rate to increase diversity, another approach may be to lower the number of grasses in the mix and increase the number of shrubs/forbs. Colowyo's Response: Colowyo and Cedar Creek Associates are not aware of any academic peer reviewed studies that have addressed this issue. The issue was raised by Cedar Creek Associates based on actual on-the-ground analysis of mine reclamation areas in the West that they have personally evaluated through their work over the past 35 years. As the majority of areas likely to be receiving an exclusive broadcast seeding application would primarily be the grassland