Fracking (8)-52

In this 2015 file photo, trucks line a Chevron fracking pad in Lost Hills during a hydraulic fracturing operation there.

A four-year-old effort to assess the effects of hydraulic fracturing on federal lands in Kern County and elsewhere in California has drawn 8,400 public comments, most of them from the Central Coast.

The responses, 2.5 percent of which have been classified as unique and substantive, are summarized in a scoping report released Thursday by the Bakersfield field office of the U.S. Bureau of Land Management.

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