WASHINGTON — The Obama administration on Thursday released new proposals for carrying out a major requirement of the federal health care law that was postponed earlier this summer. At issue is how to gather information that would allow the government to enforce a requirement that companies with 50 or more workers provide affordable health insurance to their full-time employees. Companies that don't comply would risk fines. The mandate was supposed to take effect Jan. 1, but in July the White House unexpectedly announced a one-year delay until 2015. Officials said more time was needed to work out information reporting requirements so they would not be too burdensome for businesses.