I believe the bias there is the conclusion that a report on a single or several gas leak incidents confirms a broader conclusion about the safety of underground gas pipes or the fossil fuel industry in general. The inclusion of the conclusion as definitive proof of a settled contention suggests that the author is searching for evidence to confirm a point of view that underground gas pipelines and the fossil fuel industry are dangerous, inherently dangerous, or more dangerous than alternatives.
An example of bias the other way would be if, instead of the current final paragraph, the article concluded with the following: “While this incident was no doubt harrowing for local residents, the relative lack of such gas pipeline leaks in relation to the millions of cubic feet of natural gas delivered to homes and businesses annually suggests that natural gas pipelines are one of the least dangerous methods for delivering heat and energy to US consumers.”