Sound energy and environmental policies require reliable forecasts of production and pollution, as well as supply response to policy actions. In this study, we describe a model for forecasting long-term production and pollution in the offshore oil and gas industry in the Gulf of Mexico under different scenarios. A model based on disaggregated field-level data is used to forecast production and pollution through to the year 2050. The time path for resource depletion is determined as the net effect of technological progress and depletion under alternative scenarios for new discoveries. We also quantify potential efficiencies that could result from changing the design of regulations from the current command-and-control regime, to an approach that allows more flexible means of achieving the same environmental goals.