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CAU-0Q5: TR-30. D. Hemendcz-memo supported conducting field trials throughout the reclamation area in Shrub test plots, grazing management, Mychorrizal inoculation.... Afield trial must have a limited duration to determine success or additional action necessary. This Six inch replacement thickness could be considered a trial with an success assessment in 3-4 years. Additionally, I would not be comfortable with a lay down of less than 6 inches, based on information in the research studies. Therefore the operator will need to assure soil thickness is laid down carefully to maintain a minimum of 6 inches. Spoil quality overall should not be limiting with the exception of specific areas of Wolf Creek overburden exhibiting low pH. Seneca Coal company is required to conduct a spoil monitoring program and bury acidic spoils. Acidic spoils encountered during the back£lling and grading operations in 1995 were covered with a 2.5 ft. top dressing of suitable spoil. With the shallower topsoil replacement thickness the Division has additional concerns for protection of the topsoil resource from erosion. The operator references reports that show that shallower soil will result in greater shrub and forb densities relative to the grass component. The operator has stated in the field (personal communication with Roy Kano) that increased shrub densities necessitate a decrease in graminoid cover with a resulting higher proportion of bare ground, hence increased erosion. Should the Division propose to approve the soil thickness reduction it follows that the operator will need to enact additional erosion control measures to protect the limited resource and to counter the greater proportion of exposed soil. I also contacted Dan Mathews. Additional suggestions Dan provided were add additional treatments to the spoil. Seneca's permit calls for ripping the spoil only in areas that appear to have slippage or compaction problems. Since the referenced research papers indicate that plant roots tend not to penetrate into the spoil beyond several inches, if a shallower topsoil replacement thickness is laid down, the plant roots will need to penetrate into the spoil to utilize any available water. Ripping the spoil prior to topsoil application may aid in root penetration. Other spoil treatments could include additions of organic matter incorporated into the surface of the spoil. Different organic material could be tried, manure, straw, municipal sludge(?). These treatments could be set up as a field trail with lazge scale plot sizes. The overall area to reclaim will be 627 acres. Divide up all of these acres with different treatments. Dan also encouraged the strip seeding approach for shrub establishment. During The 1996 Billings Reclamation Symposium, Mr. Richard Stevens, Utah Division of Wildlife, stressed the importance of seeding shrub species separately from grasses, (Dan Mathews report on 1996 Billings Symposium). Seneca may want to confer with Mr. Stevens to get information to aid in establishment of shrub species. Thoughts on additional erosion control measure include but are not limited to: contour furrows, soil stabilizers (soil seal, etc.), strip seeding, mulch, cover crop, netting on steeper slopes.....