[3][4][5] An estimated 500 US gallons (1,900 L; 420 imp gal) of Mercaptan, the chemical odorant added to natural gas to help detect leaks, spilled into the soil and groundwater for six months, according to Alabama state environmental officials.

[7][8] Mobile Gas officials maintained that the odor had nothing to do with their operations; they did not publicly acknowledge the leak or the lightning strike until April 2012.

[6] In subsequent court documents, Mobile Gas acknowledged the leak, but claimed the responsibility is with the waste cleanup firms they had hired to get rid of the spilled chemical.

[3][9] Sempra Energy also owns the well that caused the massive 2015−16 Aliso Canyon gas leak in the Santa Susana Mountains and San Fernando Valley of Southern California.

[3][4] In 2015 Mobile Gas started operating a new water pollution remediation ozone treatment process system.