Stop the EPA Act of 2015

Stop the EPA Act of 2015 Amends the Congressional Review Act to require congressional approval of major rules issued by the Environmental Protection Agency (EPA). (Currently, a rule goes into effect unless Congress disapproves it.) Nullifies the EPA's existing major rules unless the EPA resubmits them for congressional review. Lowers the annual economic impact threshold from $100 million to $50 million for a rule that is deemed to be a major rule. Expands the criteria for an EPA regulation to be deemed a major rule to include that the rule will have a significant impact on a substantial number of agricultural entities or it will implement a carbon tax. Expands the EPA's reports to Congress and the Government Accountability Office (GAO) to include: (1) a classification of each rule as a major or nonmajor rule with an explanation of the economic effects of the rule, (2) related regulatory actions taken by the EPA or another agency, and (3) any jobs added or lost. Allows Congress to consider approval of a major rule only once in a Congress. Gives Congress 70 session days or legislative days to approve a rule. Requires the GAO to estimate the economic cost imposed by all of EPA's rules.