415 ILCS 160/27
The owner or operator of an underground natural gas storage facility shall create procedures for a suspected natural gas leak or suspected unintentional release from an underground natural gas storage facility that is identified by either the Department or the owner or operator. The procedures shall contain guidance to direct the owner or operator to, if possible, collect the gas from the suspected leak or suspected unintentional release for purposes of testing and verifying the source of the gas.
Collecting and testing shall be performed by an independent contractor at the expense of the owner or operator. Testing of the gas shall be performed using either gas chromatography or isotopic analysis to determine if the gas composition has markers of thermogenic origins that are indicative of pipeline gas. If the quantities released are insufficient to perform a test or if quantities are insufficient to confirm a leak exists, the owner or operator shall notify the Department, and no further action related to the collection and testing of the gas is required by the owner or operator. Previous failed attempts to collect and test the gas at the same site shall not remove the owner's or operator's responsibility to collect the gas and verify the source of the gas if a sufficient amount of gas for collection and testing is available later.
The owner or operator may acknowledge that the leak or unintentional release is from the underground natural gas storage facility and treat it as a verified facility release in lieu of performing collection and testing.
The owner or operator must have procedures to be used if the gas is identified or conceded to be a verified facility release. The procedures shall provide guidance on when atmospheric conditions within a dwelling resulting from a verified leak pose health or hazard issues. The owner or operator shall offer, at the owner's or operator's expense, reasonable lodging and accommodation as determined by the owner or operator to those living in the domicile for the duration of the health or hazard issue.
The owner or operator shall perform sampling at a frequency as determined by the owner or operator for natural gas in private drinking water wells in the areas determined by the owner or operator impacted by the leak or unintentional release. The owner or operator shall maintain routine monitoring of the areas impacted by the leak or unintentional release as determined by the owner's or operator's procedures.
If natural gas is detected at levels posing health or hazard issues as determined by the Department of Public Health, the owner or operator shall offer and maintain gas water separators, at the owner's or operator's expense, in affected areas impacting the water supply, including domiciles. Where gas water separators are provided, the gas water separators shall be approved and installed in accordance with the Illinois Plumbing License Law, and any rules adopted thereunder, and shall be accompanied by an approved disinfection system or other associated water treatment device necessary to provide potable water to the affected area.
With the property owner's or occupant's consent, the owner or operator of an underground natural gas storage facility shall provide, install, and maintain natural gas detection devices, at the owner's or operator's expense, determined to be appropriate by the owner or operator in the affected areas, including domiciles, to monitor the presence of natural gas. The owner or operator shall maintain and calibrate the devices according to the recommendations, if any, set by the manufacturers of the device. The owner or operator shall provide the device manufacturer's specifications to the property owner or occupant for the specific gas detector, including the installed functions and the alarm levels set on the installed device. The alarm shall be set no higher than 25% of the lower explosive level for methane. If the property owner or occupant denies consent, the owner or operator of the underground natural gas storage facility shall notify the Department, and no further action related to the installation of devices is required by the owner or operator.
The owner or operator shall maintain routine monitoring of the areas impacted by the leak or unintentional release by method and frequency as determined by the owner or operator and create a schedule to be shared with the Department of Natural Resources, the Environmental Protection Agency, and the Department of Public Health. If the Department of Natural Resources, the Environmental Protection Agency, or the Department of Public Health determines that the monitoring schedule is insufficient, then the owner or operator shall defer to the most rigorous recommended schedule. The owner or operator shall undertake a comprehensive inspection to an extent as determined by the owner or operator.
Monitoring of the area impacted shall be maintained for a period after corrective action is completed. The post-correction monitoring period shall end as prescribed in the owner's or operator's procedures or otherwise required by the Department.
415 ILCS 160/27