Ma1-erial removed from the Ivishak River was used for the construc- 

 tion of facilities associated with oil exploration. Gravel extraction was 

 accomplished by scraping unvegetated, mid-channel gravel bars within the 

 active floodplain of the Ivishak River. Two separate winter gravel removal 

 operations were conducted at this location with 115,000 m extracted during 

 March and April 1972 and 3,800 m extracted during November and December 

 1974. Information pertaining to the size of the gravel removal area is not 

 available because removal occurred on randomly located gravel bars within 

 the permit area; however, the average depth of excavation planned for the 

 1972 operation would require approximately 40 ha of exposed material. 



Three separate gravel removal areas were observed in the field. The 

 upper area is located upstream from the airstrip in the left quarter of 

 the active floodplain. The middle area lies in the middle of the flood- 

 plain covering an area equivalent to the upstream one-third of the air- 

 strip. The lower area lies about one-third of the way across the flood- 

 plain from the left bank, just downstream of the downstream end of the 

 a irstr i p. 



Vegetative clearing, overburden removal, or dike construction were 

 not necessary at the site. Gravel ramps were used for access to the flood- 

 plain over the river bank at most points of entry, however, at the down- 

 stream access point the 2-m incised bank was cut instead of protected by 

 gravel fill. Two gravel haul roads 90 to 150 m long connect the airstrip 

 to the material site. During 1972 and 1974 dozers were used to rip and 

 stockpile material for front-end loader transfer to scrapers and trucks. 

 Maximum excavation depth was to the existing water level at the time of 

 the gravel removal operation. 



Rehabilitation measures used in 1972 and 1974 were similar: depres- 

 sions were filled, stockpiles were leveled and gravel ramps were removed 

 prior to breakup. Various aspects of this site are shown in Figure 71. 



Shaviovik River. The Shaviovik River is a medium, sinuous river which 

 originates in the Brooks Range at an elevation of 909 m and flows for 95 km 



49 



