I thought US Troops were leaving Iraq ??

I bet you thought so too?? It doest appear to be true. This is a very small example:

14th Combat Support Hospital Prepares to deploy to Iraq

Tallahassee-based 779th Engineer Battalion deploying to Iraq soon

3rd Brigade moves out to Fort Irwin before Iraq deployment

Maine Air National Guard members deploy to Iraq

Combat tracking team deploying to Iraq

3rd ID is Iraq gameplan 'closer' - Units training up for next deployment

Oregon Army National Guard's 41st Infantry Brigade Combat Team Deploying to Iraq in July

Air Cavalry troops deploy for Iraq, to train in OK

And heres a WTF moment/ Bet they'll be the cheapest contractors in Iraq. I cant believe they're being used this way.
3RD Infantry Division Trains for New Mission to Iraq
The mission for the Third Infantry Division’s upcoming deployment to Iraq has changed.
Leading the invasion into the country seven years ago they are now charged with rebuilding the country.
One of their tasks will be helping to develop infrastructure such as sanitation, water and sewer services. Because these soldiers are rather un familiar with these areas they met with the City of Savannah’s Sanitation Bureau for some help.