The Committee, headed by former CVC Pratyush Sinha, said there were "serious anomalies" with regard to claiming depreciation by companies which earlier owned these coal blocks.
"In almost all the cases, certification of statutory auditors was either not available or was not satisfactory," the report of the Committee said.
It further said that different companies owning the coal blocks had charged depreciation at different rates on the same class of assets.
"In one case, the same company had charged depreciation at different rates on the same class of assets for two of these coal blocks."
Following the deallocation of coal blocks by Supreme Court in September last year, the Coal Ministry had formed a Committee under the chairmanship of Sinha for valuation and assessment of running coal mines.
The Supreme Court had cancelled 204 coal blocks, out of which 42 were functioning.
In the first phase, the Committee selected for scrutiny 25 coal blocks which had been put up for auction by the government.
The report further said that a few companies re-valued their assets but did not provide clear details of pre-revaluation values of their assets relating to coal mining activities in their annual reports.
In one case, the assets amount claimed appeared to be highly over-valued, the report said, adding that the claims "made and details furnished did not tally with the audited annual accounts for financial year 2013-14."
In some cases, it said the claims furnished by the company in response to the Coal Ministry letter dated November 28, 2014 differed from the earlier claim furnished in response to the Ministry of Coal letter dated November 11, 2014.
The government has put for offer 46 coal blocks whose auction is due next month.