The final rule was published in the Federal Register today, which means it will take effect on 12/28/16. All the information has been posted on EPA’s website here: https://www.epa.gov/wqs-tech/water-quality-standards-regulations-washington#fed
The docket is also now available (which is also available on the main link above) here: https://www.regulations.gov/docket?D=EPA-HQ-OW-2015-0174. The docket includes the response to comments and economic analysis – direct links to these documents below.
Response to comments: https://www.regulations.gov/document?D=EPA-HQ-OW-2015-0174-0427