HOBOKEN, N.J. (AP) — Gov. Chris Christie vetoed legislation again Friday that would have banned the state from treating or storing waste products from natural gas drilling.

Christie said the proposed ban on treating, disposing or storing wastewater and other byproducts from hydraulic fracturing, or fracking, appeared to violate the interstate commerce clause of the U.S. Constitution. He vetoed a similar measure on the same grounds in 2012.

“The United States Constitution has not been amended since I vetoed the Legislature’s last attempt at a fracking waste ban in 2012," the Republican wrote in his veto message. "Likewise, Dormant Commerce Clause jurisprudence has not changed in a way that would cause me to sign a bill that I previously rejected on constitutional grounds."

Environmental activists who pushed for the ban said it would have protected fragile waterways and drinking water from harmful chemicals, and criticized the governor in a series of statements.

“Gov. Christie’s veto doubles down on his same mistake from two years ago,” said Doug O’Malley, the director of Environment New Jersey. "Fracking waste is a clear and present danger to our waterways, and the Legislature should act to overturn Gov. Christie’s ill-considered veto."

Assembly Democrat Reed Gusciora, who co-sponsored the legislation, said the decision "puts New Jersey in the Twilight Zone of ’Junk Science’ states."

There are currently no fracking operations in New Jersey, but it is a big industry in neighboring Pennsylvania and some New Jersey facilities have handled the wastewater produced.