Outgoing Secretary of Labor Hilda Solis. Carlos Osorio/AP Photo.

Just over a week after her resignation, it appears Secretary of Labor Hilda L. Solis' final major act will be the toughening of American mine safety rules. Along with Joseph Main, Assistant Secretary of MSHA (Mine Safety and Health), Solis announced a final action to strengthen the country's current mine regulations in a phone conference Thursday afternoon.

The final rule revises the Federal Mine Safety Act of 1977 to allow MSHA to issue POV (pattern of violation) notices without first issuing a potential POV notice. It also establishes general criteria to identify mines with patterns of violations and emphasizes mine operators' responsibility in monitoring their own mine's compliance with federal regulations.

"There has been recognition by many that the system has been broken, with no mine being placed on POV status until 2011 - 33 years after the law went into effect," said Main in a statement.

In 2011, MSHA established an online system where mine owners, miners, and citizens can monitor the safety of particular mines based on POV benchmarks. The final rule will continue to make the online resource available.

Born in Los Angeles, Solis was raised far from the coal mines that are now her concern.

"Mining wasn't a way of life for me and my family. But that all changed for me on April 5, 2010," said Solis.

In 2010, an underground explosion at the Upper Big Branch coal mine killed 29 men in Raleigh County, West Virginia. Solis said the new rule will hold mine owners and operators accountable when they disregard federal safety regulations.

"Upper Big Branch impacted the entire mining enterprise - families, communities, and company members," said Solis.

The final rule's announcement comes on the same day that the previous Upper Big Branch superintendent, Gary May, was sentenced to nearly 2 years in prison on a federal conspiracy charge.