Pipeline Modernization and Consumer Protection Act - Requires each operator of a gas pipeline facility, in accordance with an integrity management program, if applicable, to accelerate the repair, rehabilitation, and replacement of gas piping or equipment that is leaking or may pose high risk of leaking.

Requires each state regulatory authority and each nonregulated gas utility, in complying with such requirements, to: (1) develop prioritized timelines to repair or replace all leaking or high-risk piping or equipment, and (2) require use of best available technology to detect gas leaks.

Directs the Administrator of the Pipeline and Hazardous Materials Safety Administration to issue non-binding best practices guidelines for identifying and classifying high-risk pipeline infrastructure and leaks for repair or replacement.

Directs the Administrator and the heads of other applicable federal agencies to work jointly to establish and publish forms that adopt a standard definition and methodology for calculating and reporting information on the causes of unaccounted-for gas.