UPDATE 1-EXCLUSIVE-Pemex study details 'severe' air quality impact from Mexican refinery

A flagship refinery planned by Mexican President Andres Manuel Lopez Obrador would have a "severe" impact on air quality and emissions could spread to nearby towns, according to an environmental study produced by state oil company Pemex and reviewed by Reuters. Large portions of the environmental impact assessment, which includes hundreds of pages of technical language, were blacked out in more than a dozen documents uploaded to a government website. However, Reuters was able to view an unredacted version.

The report drafted by Petroleos Mexicanos, as Pemex is officially known, was submitted on June 12 to Mexico's oil industry environmental regulator ASEA, which has about three months to review it. ASEA, whose director is a presidential appointee, could agree with Pemex's findings or it could come to a different conclusion and then order changes to reduce the environmental impacts.

Pemex declined to comment. It referred questions to the energy ministry, which did not respond to messages seeking comment. The $8 billion refinery, to be located in the Gulf Coast port of Dos Bocas in Lopez Obrador's home state of Tabasco, was a signature campaign promise of the left-leaning energy nationalist.