President Obama will appoint a new energy secretary and new head of the Environmental Protection Agency today, according to a White House official. Obama is nominating MIT scientist Ernest Moniz to head the Energy Department and EPA veteran Gina McCarthy to run the environmental agency. She currently serves as EPA's assistant administrator for air and radiation. The president will announce the nominations during a White House ceremony this morning. Both posts require Senate confirmation. Obama also plans to nominate Walmart Foundation chief Silvia Burwell as his next budget director.