The amount of financing from equity could be driven simply by the the terms of the debt, as debt will be senior to equity. For example they may need to use the equity cash first to get the project to some point and then the debt kicks in.
Reading between the tea leaves here...this likely has no implied meaning to what LEGG's final payment will be.
Customary is to pay for the materials or equipment up front. BWCC isn't going to carry the cost of the equipment manufacture on its books. If one assumes the usual of 50% materials, 50% labor then a large chunk of the $72.5M is in sync with the $186M awarded BWCC. What's left of the cash goes to local contractors to get the facility ready for BWCC in the fall of 2013.