In June, the ceremonial shovels kicked off construction for Ballpark Commons, the $125 million mixed-use development and baseball stadium being constructed adjacent to The Rock Sports Complex in Franklin.  The project encompasses over 200 acres (including the existing Rock Sports Complex) and will feature a 2,500-seat stadium for minor league baseball and home to the UWM Panthers, commercial and retail businesses, apartments and various entertainment and active lifestyle features. The underlying story is that a portion of the complex will be built and operated on a former Milwaukee County owned solid waste landfill that the developer, led by Mike Zimmerman, CEO of ROC Ventures, purchased from the County.  Sigma is serving as the environmental engineer to support environmental challenges of the project by meeting Wisconsin Department of Natural Resources requirements that involve a new methane control network, building venting, waste management, and related plans for long-term operation.