Filing: Washington Gas had plans to fix equipment that led to deadly explosion

A new filing from the Maryland Public Service Commission says Washington Gas planned to fix a piece of equipment that led in part to a deadly apartment explosion. 

The order says Washington Gas planned to replace nearly 67,000 mercury regulators across its network of customers. The work was supposed to be done over 10 years between 2003 and 2013, but the document says the state doesn't have any evidence, "how or whether the company took any steps to remove the mercury service regulators." 

According to the National Transportation Safety Board, the 2016 blast at the Flower Branch apartments happened after gas accumulated because of a regulator which failed and was not connected to a vent line. 

The explosion killed seven residents and injured dozens more. 

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The commission gave Washington Gas 30 days to respond to its filing and the company could face fines. 

A Washington Gas spokesman told FOX 5, "We are preparing a response to address the issues raised in the order and we will be submitting our response to the commission in a timely manner."