Superfund Equity and Megasite Remediation Act of 2007 - Amends the Internal Revenue Code to reinstate the Hazardous Substance Superfund financing rate and the corporate environmental income tax, except in certain calendar quarters in which the unobligated balance in the Hazardous Substance Superfund exceeds $5.7 billion. Provides for a 50% increase in the Hazardous Substance Superfund financing rate and the corporate environmental income tax between 2008 and 2013 to fund response actions at Superfund sites estimated to cost more than $50 million (megasites) or which pose high health risks.
Establishes the Megasites and High Risk Sites Cleanup Account in the Hazardous Substance Superfund. Transfers to such Account revenues resulting from the temporary 50% increase in the Hazardous Substance Superfund financing rate and the corporate environmental income tax.
Requires the Administrator of the Environmental Protection Agency (EPA) to report to Congress annually on the progress of response actions funded by the Hazardous Substance Superfund.