CREATE TABLE table_63769 ("Coaster Name" TEXT, "Park" TEXT, "Location" TEXT, "Track" TEXT, "Builder" TEXT, "Year Opened" TEXT)

Which year opened is located in west mifflin, pennsylvania?
SELECT "Year Opened" FROM table_63769 WHERE "Location" = 'west mifflin, pennsylvania'
SELECT "Year Opened" FROM "table_63769" WHERE "Location" = 'west mifflin, pennsylvania'