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A protestor holds a sign against fracking during a demonstration outside of the California Environmental Protection Agency (EPA) headquarters on July 25, 2012 in Sacramento, California.
The debate over fracking to extract oil and gas has focused largely on the chemicals injected underground, and their potential effect on public health.
Now environmental groups are turning their attention to the waste produced by simply drilling a well in the first place. The California Report's Sasha Khokha reports water regulators in the Central Valley will consider the issue tomorrow