The political piece of the Millennium Tower sinking saga kicks off with a hearing today, and Supervisor Aaron Peskin is already taking charge and "grilling" the Department of Building Inspection on the tower's approvals process, as ABC 7's Carolyn Tyler tweets from the Board of Supes' hearing room. The hearing at the Government Audit & Oversight Committee today, as Peskin promised last week, is intended "to find out who knew what and when they knew it," among city officials, as well as the developers.

Peskin has already reportedly snapped at someone saying, "This isn't somebody's leaking toilet. This is a big deal."

The national news media is also now covering the hearing, with CNBC leading with "The Leaning Tower of San Francisco." They note that among the high-profile tenants in the luxury condo tower are "NFL Hall of Fame quarterback Joe Montana; San Francisco Giants outfielder Hunter Pence; [and] Tibco founder and Sacramento Kings owner Vivek Ranadive."

Peskin spoke to CNBC before the hearing saying, "We are in the midst of a huge building boom. We should make sure that we are building to the highest standards, and that we are building the safest buildings that we can in San Francisco, which is a seismically challenged part of the world."

As discussed yesterday, the blame game continues between the TJPA and Millennium Partners, with the latter blaming the Transbay Transit Center project and the "dewatering" it did to soil adjacent to Millennium Tower for causing the tower's excessive sinking.

Whatever the cause, the problem is solvable in the long term. CNBC reaches out to a Stanford expert, associate professor of civil and environmental engineering Michael Lepech, who says that the two available options are both costly and not necessarily designed for a building of this size. One would be to shore up the buildings foundation with hydraulic jacking and new piles driven deeper, and another would be to add chemical stabilizers to the soil underneath.

Peskin remains intent on figuring out whether there was any political maneuvering to get the Department of Building Inspection to sign off on a tower that already may have been showing excessive settlement.

As I type this, Peskin is grilling former DBI deputy director Raymond Lui about a strongly worded 2009 letter to the developer and its construction engineers about the observed excessive settlement and "differential settlement," i.e. tilting, that was already being observed at that time, just as the building was completed. Lui says he does not recall what information led him to write the letter. "To your knowledge do you know of another letter like this written to any other developer about a project?" Peskin asked. "Not that I'm aware of," Lui said.

"With the response we received from the engineer of record," Lui says, "we believed that they had it under control."

All previous coverage of the Millennium Tower saga on SFist.