CHATTANOOGA, Tenn. (AP) — Amazon.com plans an expansion of its Chattanooga distribution center that will eventually add hundreds of jobs.The manager of the center, Sanjay Shah, told the Chattanooga Times Free Press that work will start this month (http://bit.ly/z7xK3e )."We're doing the expansion to meet demand," Shah said last week.The distribution center's operating area is currently the size of 17 football fields and will be expanded to the equivalent of about 28 football fields. The cost wasn't disclosed.Currently the Seattle-based company has more than 2,000 workers at its round-the-clock operation in Chattanooga."We'll have 5,000 (workers) at some point this year" at Amazon's facilities in Chattanooga and neighboring Bradley County, he said.The company said centers that are planned in Rutherford and Wilson counties, combined with existing facilities in Wilson, Hamilton and Bradley counties, have Amazon investing more than $270 million in Tennessee.Amazon last year agreed to start collecting Tennessee sales taxes in 2014.At the center, computer stations are set up along conveyor lines for personnel to scan and process items that are for sale on the website of what has become the world's No. 1 Internet retailer.Shah said the facility keeps an inventory of some goods in anticipation of future orders.Employee Alice Donohoe of Chattanooga, a packer, said the holidays were very busy.She said she joined Amazon about 10 weeks ago."Here, I have a chance to grow," she said.Gov.