A contentious plan to drill up to 166 oil and gas wells on the southeastern fringe of metro Denver, near hundreds of homes and the Aurora Reservoir — a drinking water source for nearly 400,000 people — will finally land before state energy regulators this week for a key decision on its fate. Neighbors worried about potential health and ecological impacts from the project want the Colorado Energy and Carbon Management Commission to say no to the plan after an extensive hearing that’s set to begin Tuesday.