OTTAWA — The Competition Bureau has published guidance on what might constitute corporate greenwashing as it begins consultations over how it will implement Ottawa’s contentious new measures aimed at preventing false and misleading environmental claims. The bureau said goals and timelines for achieving environmental objectives such as reducing carbon emissions must be supported by clear and specific plans, and not just be aspirational. It also warned companies against trying to shield their green assertions with disclaimers. The agency issued the commentary on Monday as it launched a request for feedback to help it formulate plans for implementing the new measures, which some companies, industry associations and provincial governments have criticized for being vague and heavy-handed. The consultation period runs to Sept. 27. Bill C-59 contains the controversial amendment to the Competition Act that puts companies at legal risk for making environmental assertions that do not stand up to scrutiny.