1988-04-11_PERMIT FILE - C1981008A (23)

Home Browse Search

The drainage ditch will be designed to handle the runoff from a 10-year, 24-hour storm event and should preclude the potential of any water quality degradation in Calamity Draw as a result of these associated disturbances within the buffer zone. Because the anticipated operations will not result in disturbance of the main channel, there should be no impact to the quantity of streamflow in Calamity Draw from the buffer zone disturbance. After mining and related activities, the following reclamation plan for the area will be implemented to help insure the reestablishment of vegetation generally similar to that which occurs within the buffer zone. The areas within the buffer zone that may potentially be affected are dominated by the graminoid component of the swale/drainage vegetation type (see Tab 10, Addendum 10-3). Nearly all of the dominant species that occur in this component are rhizomatous species capable of forming dense sods, while also reproducing from seed. These species, unfortunately, are not available from plant material suppliers. Adjacent undisturbed stands will rapidly reinvade the reclaimed areas by means of plant popagules (seed or extension of rhizomes). Anticipated disturbance relates only to those activities necessary to the construction of the diversion ditch. Salvaged topsoil will be replaced following necessary grading to reclaim the ditch and shape the final contours. As part of seedbed preparation, the replaced topsoil will be disked with the first pass made partially into adjacent native vegetation to "tie" the reclaimed and native sites together. This operation also serves to pull and mix native plant rooting materials into the edges of the reclaimed area, thus hastening reinvasion. As with any sod farming species, the cutting up and dispersal of rooting materials tends to increase regeneration and stimulate the stand. In the interim, Seed Mix #6, Irrigated Pasture-Poorly Drained Phase (Tab 22, Revegetation Methods - Irrigated Pasture) will be seeded on all reclaimed areas on or immediately adjacent to the buffer zone in order to stabilize the site. Reed canarygrass, contained in Seed Mix #6, is found in the undisturbed swale/drainage vegetation type (Tab 10, Addendum 10-3). Creeping foxtail (Alopecurus arundinaceus) is one of the few other grasses available on the market that has the potential to tolerate poorly drained sites. Creeping foxtail is also a valuable species for wildlife, providing both early spring growth for food and later growth for nesting and escape cover. Birdsfoot trefoil (Lotus corniculatus) is included in the mix because it is adapted to wet or poorly drained sites and will provide soil nitrogen benefits to the established plant community. It is a non-bloating legume 16-8 Revised 04/11/88