The exemption had been intended to shield small coal operations from the law's strict provisions on land restoration.
The House had passed a bill last year with much stricter provisions than those in the version announced today.
Five states passed laws in the last year, and in three, stricter provisions take effect July 1.
Last year, the House approved, 313 to 108, a bill with even stricter provisions on debtors.
Despite the seemingly strict provisions of the law, many people were exempt from prosecution.
Officials said the selection had taken longer than expected, partly because of the law's strict provisions against conflicts of interest for board members.
Under existing legislation, we can and shall introduce stricter provisions.
The Community called for stricter provisions in certain respects but did not manage to push them through.
We all need to get together and, where necessary, supplement the strict provisions that we have in place.
We need very strict provisions to protect individuals who are incapable of giving their informed consent.