Earlier this week it was reported that the safety of the cast iron main is under scrutiny for being the cause of the Allentown explosion which killed five people on February 10.

Reports are suggesting that the cause of the explosion is likely from a natural gas leak originating from a cracked cast iron main. Cast iron is subject to corrosion and decay and is rarely used in today’s natural gas pipeline construction. The 83-year old pipeline is badly in need replacement. While today most pipelines are made of plastic (polyethylene), there are 63,000 miles of cast iron pipe that run across Pennsylvania alone. U.S. Senator Bob Casey (PA) instructed UGI Utilities and other natural gas companies to replace their outdated cast iron network.

In my earlier posting, Natural gas fireball in Philadelphia - where next? I reported how reminiscent the January 18 Philadelphia explosion was to the San Bruno incident. I didn’t realize it’d be only days away from the next explosion. In fact we seem to have had our share of incidents lately,

• January 18, 2011 - A gas main being repaired in Philadelphia, Pennsylvania explodes, killing a repair crew member and injuring 6 others.
• January 24, 2011 - Gas pressure regulators failed and caused a gas pressure surge in Fairport Harbor, Ohio, igniting fires burning several homes and one apartment, damaging 45 furnaces, 10 boilers, 19 water heaters, and 10 other gas appliances. 
• February 10, 2011 - 5 people killed and 8 homes destroyed in a gas explosion and fire in Allentown, Pennsylvania.
• February 10, 2011 - a 36 inch gas transmission pipeline explodes near Lisbon, Ohio.

It’s unfortunate that it takes accidents like these to bring to light the aging network of pipelines which are not just limited to San Bruno and Pennsylvania, but are nationwide. It is time that we become more proactive and advocate safety and damage prevention of our gas pipelines.