A brush fire scorched about six acres of vegetation in West Covina Monday, briefly threatening some structures before crews got the upper hand on the blaze. The BKK Fire was reported at about 1:40 p.m. Monday in the 2200 block of South Azusa Avenue, and it was contained as of 3:10 p.m., according to the Los Angeles County Fire Department. The blaze occurred at the site of the former BKK Landfill. The cause of the fire was under investigation. So…