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Surface Water Effects and Mitigation Drainage and sediment control measures implemented by the applicant are sufficient to ensure that the quality of water downstream from the site is not impacted. The only impact on water quantity is the consumptive use of approximately 6 acre-feet per year. The Terror Creek Loadout withdraws water from two sources. water for dust suppression is supplied by senior water rights from the Deertrail Ditch. The ditch withdraws water from Hubbard Creek. Use averages 5,000 gallons per day (5 .6 acre-feet/year). Previously, this water was used to irrigate orchards where the loadout ie now located. A domestic well which supplies about 450 gallons per day (0.5 acre-feet/year) is used for domestic use at the loadout office and bathhouse. Terror Creek's consumption amounts to 0.002 of the North Fork's mean annual yield at Somerset. This amount of consumption ie considered by the Division to be insignificant. Upon final reclamation, the essential hydrologic functions of the site will be restored. The essential hydrologic function which must be restored within the affected area is the capability of the site to support flood irrigated agri- cultural production levels comparable to pre-disturbance levels. The major components of the reclamation plan which will ensure that this essential hydrologic function is restored are the following: Regrading of the loadout pad and diversion structures to approximate original contour so as to allow for distribution of irrigation water as was practiced prior to disturbance. Scarification and ripping of the regraded slope so as to relieve compaction and allow for root penetration and aeration. Replacement of a sufficient depth of a plant growth medium so as to provide for a water holding capacity within the rooting zone that will support irrigated agricultural productivity comparable to pre-disturbance levels. Soil physical data and analyses supplied by the applicant for topsoil, subsoil and colluvium indicate that available water at field capacity would vary from 3.41 inches to 4.81 inches within the identified rooting zone (44 inch depth) in orchard land immediately adjacent to the disturbed area. The analyses indicate that the physical characteristics and water holding capacity for the colluvial deposit are con- sistent throughout its entire depth. Thus mixing of the material as a result of construction and reclamation would not reduce water-holding capacity. The replacement of 10 inches of topsoil rather than the 13- inch depth which existed prior to disturbance will reduce the amount of water stored within the rooting zone by approximately .33 inches. However, the reconstructed root zone (10 inches of soil and 34 inches of colluvium) would hold 3.51 inches of water at field capacity, which is comparable to orchard soils adjacent to the permit area. Terror Creek Loadout Page 13