Parakh was examined for nearly eight hours yesterday during which he was given number of queries relating to allocation process and reasons for changing his screening committee decision which had rejected Hindalco's application.
After examination, when he was asked whether he was satisfied with the questioning process, as he had alleged in his book that on previous instances inspector-level officers with no experience of policy formulations were involved in his examination, Parakh had said he was satisfied.
"The whole idea of the questioning is to understand. I am in the process of making them understand. They have a point of view. I am trying to put my point of view," he had said.
Parakh was questioned by a team led by a Superintendent of Police (SP) level officer, which was monitored by a Joint Director and he was given access to all documents related to the case, sources said.
69-year-old Parakh, who retired as Coal Secretary in December 2005, has been accused in a CBI FIR of abusing his official position to grant a coal block to Hindalco, an Aditya Birla Group company.
CBI had last year registered a case against Parakh, Birla and unnamed officials of Hindalco and the Coal Ministry.
Birla and Hindalco have denied allegations of irregularities.
The agency has alleged that during 2005, these persons had entered into a criminal conspiracy and the then public servant (Parakh) abused his position and showed undue favour to the Odisha-based industry in allocation of Talabira II and Talabira III coal blocks.
CBI has also quizzed former Minister of State for Coal Dasari Narayan Rao and the Prime Minister's Advisor T K A Nair in the case.