Continued...
Sand vs what - really?  Makes no difference
According to the EPA, fracking operators withheld 11 percent of the chemicals they reported to FracFocus between January 2011 and February 2013. As a reason for not disclosing information, companies said the information was “confidential,” a “trade secret” or “proprietary.” The EPA also found that 70 percent of disclosures withheld one chemical or more.

But the rate of withheld chemicals may have increased since then, according to researchers at Harvard University.

Kate Konschnik, the policy director at Harvard’s Environment Law Program, and a colleague found that 18.9 percent of fracking chemicals reported on over 53,000 forms filed to FracFocus between November 2012 and April 2015 “were intentionally withheld from public disclosure.” And 92.3 percent of these forms included “at least one withheld ingredient,” the researchers reported in their paper published in the journal Energy Policy in January 2016.