On instruction from the regulatory agency Nuclear and Industrial Safety Agency, TEPCO submitted an almost completely blacked-out document. Not satisfied, to say the least, the committee asked for re-submission.
NISA accordingly instructed (the link is in Japanese, PDF) TEPCO again on September 8, telling the company to "report to the agency by 6PM as to what conditions are necessary for the disclosure of the information, if any".
On September 12, TEPCO submitted the front cover and the table of contents of the document "Operation Manual for Reactor 1 (Severe Accident)", 3 pages total, with 48 lines out of 50 were blacked out. All the lawmakers in the committee could read was "fire extinguishing line" and "inert gas".
TEPCO's Matsumoto explained that the manual is a company's internal document and not for public consumption, and the company has to protect intellectual properties and the physical protection of nuclear facilities. (Information from Asahi Shinbun, 9/12/2011)
We can blame TEPCO all we want. But again, the company is following instruction from NISA, and NISA makes no effort to have the information disclosed.
The Diet committee is asking for re-re-submission.