Sunset Crater well No. 2 / Sunset Crater National Monument, Arizona

Christensen, Paul

Sunset Crater well no. 2 was constructed next to Sunset Crater no. 1 well to replace the no. 1 well which failed. The well is located in Bonito Park just off the west boundary of the Sunset Crater National Monument. Drilling problems plagued the project and dragged out the completion of the well. Total depth of the well is 2211 feet BSL. Static water level is 1960 feet below surface well. The aquifer is the Supai group which is composed of red fine-grained sandstones and siltstones. Porosity and permeability in the aquifer are mostly due to fractures and poor cementation of the aquifer rock. The saturated and penetrated portion of the aquifer is 250 feet thick. Unconfined groundwater conditions exist. The screened·portion sits 14 feet off total depth and is 80 feet long. The well was packed with a coarse-grained beach sand to bar the entrance of the fines from the Supai group rocks. A 73-hour aquifer test at a discharge rate of 22.3 gpm, using the abandoned no. 1 well as an observation well, gave a transmissivity value of 4800gpd/ft and a storage coefficient (specific yield) value of 0.0090. Predicted drawdown in the production well was 6.0 feet. A total drawdown of 2.0 feet occurred in the observation well. The static water level in the observation well recovered 90 per cent in 3 hours after pumping ceased. Specific capacity of the well is 3.7 gpm/ft drawdown. The water from the well has a total dissolved solid content of 565 mg/l. The water bears an unpalatable taste, probably due to iron and manganese, but is potable.