From a short note in The Times on May 29 that I saw on my trip back from London:
"The American civil engineering company formerly known as CH2M Hill has struck a deal with Apollo Global Management to invest $300 million in a transaction that will solve its cashflow problems and values the engineering group at about $2 billion. The group played a leading part in the 2012 Olympics and has roles on HS2 and UK nuclear decommissioning projects."
From the Apollo website - interesting in the context of who Apollo invests in and their investment goals. Also the CH2M press release.