据电动公用事业国家电网报道，爆炸性范围的天然气泄漏强迫劳伦斯，马萨诸塞州劳伦斯，以撤离他们的房屋，据电动公用事业国家电网报道，向1300多名客户削减了电力，以避免像去年一样的另一场灾难天然气爆炸和火灾在劳伦斯和波士顿以北的其他两个城镇。泄漏是在联邦官员呼吁更改国家管道法规的几天之后，他们发布了有关2018年9月13日灾难原因的最终报告。

After the leak was discovered in a high-pressure pipeline at 3:15 a.m. on Sept. 27, hundreds of people were evacuated to a shelter at a local middle school as Columbia Gas of Massachusetts cut gas to 146 customers and searched homes and businesses "door-to-door" for leaked gas, according a Columbia Gas鸣叫。The Boston Globereported泄漏的气体线是在去年灾难造成的，造成一名人，将22人送往医院的，并损坏了劳伦斯的131个建筑物，安多佛和北安多佛造成了131个建筑物。马萨诸塞州紧急事务管理局称，尚未报告任何火灾或爆炸。

The state determined the gas main was punctured during a routine check in preparation for road paving. Columbia Gas has identified 45 gas valves that the Dept. of Public Utilities has required Columbia Gas and mutual aid partners to inspect immediately. All construction in the area has been suspended until it can be determined that older gas valves have been disabled.

Residents were returning home as inspections on valves were completed. The investigation is ongoing.

Report Findings

Just days earlier During a Sept. 24 hearing in Washington, D.C., the National Transportation Safety Board (NTSB) released its final report on the causes of last year's disaster and issuedfive new safety recommendations, including calls for revising federal regulations “to require overpressure protection for low pressure natural gas distribution systems that cannot be defeated by a single operator error or equipment failure.”

An erroneously over-pressurized gas line caused last September’s disaster. Furthering its初步发现NTSB在9月24日的听证会上表示，哥伦比亚天然气在灾难前几年犯的错误 - 以及省略了用于管道替换项目的关键传感线计划，并指出了过度压力的配电系统。董事会表示，“工程管理薄弱”导致工作人员放弃了铸铁主，而无需将调节器传感线重新安置到新的聚乙烯主体。

The board also called for removing exemptions in 31 states—including Alaska, Arizona, Connecticut, Maine, and New York—so that all future natural gas infrastructure projects require licensed professional engineer approval and stamping. Massachusetts only adopted such a requirement after the disaster. “It’s important to note that in all 50 states you have to have a license to cut hair, “said Bruce Landsberg, NTSB vice chairman, “but you can design a gas system that affects public safety and 31 states exempt you from having a license or even an engineering degree.”

Lori Traweek, the American Gas Association’s chief operating officer, said the association, “continues to learn from this tragic incident and has been focused on understanding exactly what happened in order to continue to improve the safety of the industry and become stronger.”

加强安全性的AGA计划包括：reporton leading practices to reduce the possibility of a natural gas over-pressurization event,指导适用于在天然气系统和董事会上安全执行工程工作功能所需的技能和知识的成员resolutionrecommending that all members implement Pipeline Safety Management Systems.

Traweek said the association is working with the NTSB and other state and local governments “to better understand the cause and help ensure that something like this never happens again.”

断开

根据NTSB的数据，马萨诸塞州的气体火灾和爆炸发生在劳伦斯的哥伦比亚气管替换项目中，高压天然气释放到低压气体分配系统中（哥伦比亚气体批准和批准）没有足够的过度压力保护。。

The board said a Columbia Gas-contracted crew overseen by a Columbia Gas inspector “was working on a tie-in project that bypassed the existing cast-iron line, directing gas pressure to a new plastic line,” minutes before the explosions. The crew left in place the existing cast-iron distribution main that still had its pressure regulator-sensing lines on it. When the old main was disconnected, pressure dropped in the new plastic line, causing the regulators to widen and over-pressurize the system.

NTSB的调查人员在爆炸后立即描述了一种“令人困惑和混乱的”情况，因为机组人员努力找到和关闭关键阀门。NTSB铁路，管道和危险材料办公室主任罗伯特·霍尔（Robert Hall）表示：“令我惊讶的是，一家经营该系统超过100年的公司无法制作地图，这是一张很容易制作的地图。”

A spokesman for Columbia Gas owner NiSource Inc. called NTSB’s investigation “an important step in the effort to enhance pipeline safety” and said it has “taken a series of steps to prevent something similar from happening again,” including installing automatic shut-off devices, accelerating implementation of a Safety Management System, enhancing emergency preparedness and enhanced mapping.

While Columbia Gas has not been fined for the incident to date, it has invested an estimated $250 million in pipeline-replacement expenses, $994 million in third party claims since the Greater Lawrence incident, and $670 million in insurance recoveries, according to Indiana-based NiSource’s second quarter 2019 earnings results published on July 31. Columbia Gas alsofaces up to $1 million in finesfor abandoning gas service lines after the explosions.

An estimated 175,000 residents and business owners affected by the disaster stand to benefit from a $143 million class-action settlement, according to a legal brief filed in the Essex County Superior Court on Sept. 26.

Lawrence mayor Dan Rivera called for the removal of Columbia Gas’s license to distribute gas in Massachusetts.” In a陈述，他说，NTSB报告表明：“这本可以避免的，哥伦比亚天然气未能实施自己的政策以及行业广泛的接受实践。”

On Notice

根据NTSB的说法，两年前很容易避免被汽油燃料和天然气爆炸点燃的大火。董事会表示，Nisource首先意识到2015年该公司向其子公司发出通知，通知他们有关肯塔基州的传感器问题，其中包括警告说，过度压力的线路，“可能会导致灾难性事件。”

此外,NTSB发现哥伦比亚气体的初始planning for the Lawrence pipe replacement project in 2015 didn’t address sensing lines. The following year, an Oct. 17 internal email at Columbia Gas noted that the sensing lines would eventually be relocated to the 8-in plastic main. But three constructability reviews conducted by Columbia Gas during the ensuing years still didn’t pick up on the fact that the plans didn’t include the sensing line relocation, according to the NTSB. “Inadequate planning, documentation and recordkeeping processes led to Columbia Gas' omission of the relocation of the sensing lines for the South Union Street Project,” said Sharon Bryson, NTSB managing director.

Robert Sumwalt, NTSB’s chairman added that, “those risks should have been identified and … mitigated … Catastrophic tragedies like this should never happen.”

参议员爱德华·马基（D-Mass。） - 关于灾难的听证会，也介绍了legislationto reform the gas industry with Sen. Elizabeth Warren (D-Mass.) and Rep. Lori Trahan (D-Mass.) in April—said the NTSB plans to discuss their findings during a community meeting in early October in Lawrence. “NiSource’s reckless actions and our loophole-ridden pipeline safety regulations led to death and disaster, with gas pressures reaching between 100 to 150 times higher than they should have been in that system,” Markey said in a陈述。“The NTSB final report confirms what Senator Warren and I found during our investigation–that this disaster was not inevitable, it was preventable.”

这个故事于10月1日更新