EnergySolutions 10-Q 2010 Q2 Quarterly report

QuickLinks -- Click here to rapidly navigate through this document

EXHIBIT 32.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        I, Val J. Christensen, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of EnergySolutions, Inc. on Form 10-Q for the fiscal quarter ended June 30, 2010 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Form 10-Q fairly presents in all material respects the financial condition and results of operations of EnergySolutions, Inc.

August 5, 2010

By: /s/ VAL J. CHRISTENSEN
Val J. Christensen,
President and Chief Executive Officer

        I, Mark C. McBride, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of EnergySolutions, Inc. on Form 10-Q for the fiscal quarter ended June 30, 2010 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Form 10-Q fairly presents in all material respects the financial condition and results of operations of EnergySolutions, Inc.

August 5, 2010

By: /s/ MARK C. MCBRIDE
Mark C. McBride,
Executive Vice President and
Chief Financial Officer

        A signed original of this written statement required by Section 906 has been provided to EnergySolutions, Inc. and will be retained by EnergySolutions, Inc. and furnished to the Securities and Exchange Commission or its staff upon request.

QuickLinks

EXHIBIT 32.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002