; and (B) program and policy recommendations to Congress to address any limitations in tracking data related to hazardous fuels reduction activities under this subsection. (c) GAO study Not later than 2 years after the date of enactment of this Act, the Comptroller General of the United States shall— (1) conduct a study on the implementation of this Act, including any limitations with respect to— (A) reporting hazardous fuels reduction activities under subsection (a); or (B) tracking data related to hazardous fuels reduction activities under subsection (b); and (2) submit to Congress a report that describes the results of the study under paragraph (1). (d) Definitions In this Act: (1) Hazardous fuels reduction activity The term hazardous fuels reduction activity — (A) means any vegetation management activity to reduce the risk of wildfire, including mechanical treatments and prescribed burning; and (B) does not include the awarding of contracts to conduct hazardous fuels reduction activities. (2) Federal lands The term Federal lands means lands under the jurisdiction of the Secretary of the Interior or the Secretary of Agriculture. (3) Secretary concerned The term Secretary concerned means— (A) the Secretary of Agriculture, with respect to National Forest System lands; and (B) the Secretary of the Interior, with respect to public lands and units of the National Park System. (4) Wildland-urban interface The term wildland-urban interface has the meaning given the term in section 101 of the Healthy Forests Restoration Act of 2003 ( 16 U.S.C. 6511 ). (e) No additional funds authorized No additional funds are authorized to carry out the requirements of this Act, and the activities authorized by this Act are subject to the availability of appropriations made in advance for such purposes.