Complex sentence: The West Valley Facility was mothballed for future use in the event of increases in the population of detained youth, but was repurposed for use as an adult day reporting center following the passage of AB 109 Realignment in October 2011.
Split into simpler sentences: The West Valley Facility was mothballed for future use in the event of increases in the population of detained youth. It was repurposed for use as an adult day reporting center following the passage of AB 109 Realignment in October 2011.