Each plant averages 35 jobs, which gives us about 3,100 ethanol-related jobs with higher salaries than local averages. Moreover, according to this study, plants generate indirect jobs and have increased corn and land prices. 70 percent of the plants are located in rural counties where population decreased between 2000 and 2006, while the national average is 50 percent of rural counties losing population during the same period. According to the study, this means that plants were located in the most economically deprimed areas.
The same applies for current facilities (67 are being built now), which are larger (and with bigger benefits, according to the ERS), 75 percent of which are placed in counties that are losing population.
Check the full report here (h/t to Ronald for the tip), because our source seems not to match the report (they could have made a mistake).