And so it begins. The new Republican chairmen of a powerful House committee and its investigative subcommittee want Obama administration officials to explain exactly how they’re implementing the health law.

It’s the first of what’s expected to be a long list of investigations that could keep Obama health officials busy gathering documents and testifying on Capitol Hill for much of the year.

The letter to Jay Angoff, head of the Office for Consumer Information and Insurance Oversight comes from Energy and Commerce Committee Chairman Fred Upton (R-MI), and Cliff Stearns, (R-FL), chairman of the Subcommittee on Oversight and Investigations.

“Because millions of Americans rely on the private insurance market for health care coverage and will be affected substantially by the actions of your office, there is substantial public interest in information about the CCIIO,” said the letter, dated Jan. 20.

The Office, renamed as a center and relocated recently from Health and Human Services Secretary Kathleen Sebelius’s office to the Centers for Medicare and Medicaid Services, is charged with implementing many of the insurance changes called for by the law.

But the transfer of the office, which many theorize is aimed at better protecting it from GOP budget cuts, is only one of the issues the congressmen want explained.

“Most troubling is that your office is currently responsible for deciding who does not have to comply with the massive new regulations imposed by the (health law),” the letter says. “Currently your office has approved waivers from the (law’s) annual limits requirements for 22 applicants.” Because the office has also rejected waiver requests, the lawmakers wrote, “We would appreciate if your office would explain how a decision is made on whether compliance with the (law) is necessary.”

To that end, it seeks a long list of documents, e-mails, and other explanations of how the office does its work and makes its decisions.

And HHS officials, including Secretary Sebelius herself, ought to keep their calendars clear for what are certain to be numerous command performances on the House side of the Capitol.

“I assure you, Secretary Sebelius will be one of the most recognized faces in Rayburn next year,” said Upton shortly after last year’s elections. Rayburn is the House office building where the committee’s offices are located.