Last summer, Scott Pruitt left his job heading the Environmental Protection Agency and within a few months had started consulting for coal magnate Joseph W. Craft III. Three weeks after leaving the Interior Department, energy counselor Vincent DeVito joined Cox Oil Offshore, which operates in the Gulf of Mexico, as its executive vice president and general counsel. Now, Joe Balash — who oversaw oil and gas drilling on federal lands before resigning from Interior on Friday — is joining a foreign oil company that is expanding operations on Alaska’s North Slope.