Penalty notices have been issued to the Integra and Mt Thorley Warkworth coal mines.
According to the NSW Department of Planning and Infrastructure both mines were issued a $3000 penalty notice for blasts exceeding the relevant sound pressure and exceeding noise compliance limits respectively.
At Vale's Integra coal mine a blast was recorded as exceeding the limit of 120 decibels.
At Rio Tinto subsidiary Coal & Allied's Mt Thorley Warkworth mine its noise monitoring equipment indicated noise levels in the Bulga area to more five decibels above those specified for its operations.
Rio Tinto voiced its disappointment over the incident.
“It is important to Coal & Allied that we meet our regulatory conditions and we are disappointed to have recorded this noise breach.
“We will continue to work closely with our neighbours and the New South Wales Government as we improve the way noise is managed at Mount Thorley Warkworth mine.
It comes only a month after miners in the region saw a reduction in the number of blast fume complaints.
The Land and Environment Court has also begun prosecution proceedings against the Mt Thorley Warkworth.
According to the department the miner failed to comply with a number of conditions relating to minimising dust in September last year.
Rio stated that "air quality across the Hunter Valley was affected by dry and windy weather conditions at this time and Mt Thorley Warkworth mine took a range of steps to minimise dust, including shutting down equipment and increased use of water sprays".
Since the initial event it is implementing a number of initiatives to improve noise and dust management such as noise attenuation of its mining fleet, operating continuous noise monitors, dust alarms around its coal hoppers, and upgrading its water fleet.
The miner is yet to enter a plea, and will attend court late next month over the allegations.
Maules Creek mine is also in the firing line.
The department has begun proceedings against he miner over "failing to disclose two reportable political donations made in March 2011 by its former directors, Todd Hannigan and Thomas Todd, in contravention of the Environmental Planning and Assessment Act".
Overall the Singleton office received 27 complaints during April, 23 of which were for noise.
Only two were related to blasting and two over dust issues.