SACRAMENTO (CBS/AP) — A federal railroad oversight board has given approval to the California High-Speed Rail Authority to start construction in the Central Valley.

The Surface Transportation Board ruled Thursday that the California project could start building the first 65 miles of the project from Merced to Fresno, as planned.

The STB previously ruled that it has oversight of the project, but on Thursday the agency granted an exemption to the state.

Congressional Republicans had asked the body to intervene and halt the state’s plan to start construction this summer.

The Surface Transportation Board said in its 67-page decision that California officials and the Federal Railroad Administration have already extensively reviewed potential environmental harm from the project and are taking steps to mitigate it.

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