William Redd opened the resort as the Peppermill Resort in 1976, and later renamed it as Si Redd's Oasis. Portions of the Oasis were closed in December 2008, due to financial losses.
Until 1990, the Oasis was the only casino in Mesquite. The Oasis' casino was closed in 2010, although the hotel was still used for overflow guests at Black Gaming's other Mesquite casinos. In 1976, William "Si" Redd – who founded the slot machine company International Game Technology – purchased the struggling property and turned it into the Peppermill Resort, later renamed as Si Redd's Oasis.
In October 1996, Redd turned over control of the Oasis to his son-in-law, Alan Green, who was named as president and sole director.
Redd's daughters, Sarah Green and Vinnie Copeland, were named trustees of the William S. despite monopoly concerns; the Black family already owned two of the city's four casinos, and the Oasis gave them 91 percent of the city's casino hotel rooms, 85 percent of the city's table games, and 80 percent of the city's slot machines.
Employees alleged that Black had lied to them and was planning to demote veteran employees and cut their salaries.
Black claimed that he rehired 800 of the Oasis' 900 employees, and that any salary cuts would be caused by Mesquite market conditions.
At the time, Redd said about the purchase, "I had lost touch with who I was -- my thing was tinkering with machines. The Oasis was a good idea and it was fun, but it never really was a money maker because it was not managed right." while other casino and restaurant operations would be gradually phased out by December 5.
Restaurant operations were expected to cease on the night of December 5.
Some slot machines were left operational at the resort's front counter to maintain a nonrestricted gaming license.
Black said that "no assurances" could be made as to when the Oasis' facilities could reopen.
During a 2010 Chapter 11 hearing, company officials considered demolition of the Oasis. said there was no timetable for demolition, and stated that the resort could reopen entirely if the local economy improved.
At that time, 16 slot machines remained operational at the casino.