Peoples Gas-Manlove Field
On December 16, 2016, Peoples Gas Light and Coke Company (Peoples Gas) reported a natural gas leak at a storage field (Manlove Field) it owns and maintains near Fisher, Champaign County. Information at the time indicated the leak was initially discovered by an employee for Peoples Gas who noticed gas bubbles in puddled water near the L. McCord #2 (MC 2) well. Peoples Gas worked with Illinois Department of Natural Resources (IDNR), the agency that regulates gas storage fields, to address the release, and had gas/water separators installed in several homes to remove methane. In late April 2017, the Illinois Department of Public Health (IDPH) notified Illinois EPA that it was aware of a gas release and that private wells had been affected.
Following communication with IDPH and IDNR, the Illinois EPA determined it should develop its own data on the contamination issue. On October 30, 2017, representatives of Illinois EPA and IDPH started visiting homes to obtain access agreements and sample both groundwater from private wells and levels of combustible contaminants in the ambient air of those homes. Thermogenic gas attributable to a man-made source, likely Peoples Gas’ release, was found in water samples collected from five separate private wells in the area of the Manlove Field. These were the same five private wells where Peoples Gas found thermogenic gas as part of its private well investigation earlier in 2017.
In October 2017, based on a referral from IDNR, the Illinois Attorney General's Office (IAGO) filed a Complaint which included counts of water pollution and impairment of resource groundwater on the IAGO’s own motion. In October 2017, the court entered the First Agreed Interim Order which required Peoples Gas to offer bottled water and methane monitoring and alert devices to households whose water supplies were impacted by the release. In January 2018, Illinois EPA separately made a referral to the IAGO for water pollution violations from allowing thermogenic gas associated with its natural gas storage field activities to infiltrate groundwater and, subsequently referred air pollution violations to the IAGO.
On September 13, 2019 the Champaign County Circuit Court entered a First Amended Agreed Interim Order (FAAIO) in People v. Peoples Gas to provide relief to Affected Households which included providing bottled water, installing and maintaining gas detectors, and offering and maintaining gas/water separators in impacted homes. The FAAIO allowed for any household whose groundwater supply has shown concentrations of methane at or above 10mg/L to obtain this relief, including households that were not identified at the time of the initial order. The FAAIO required Peoples Gas to complete a comprehensive inspection of all the facility’s injection/withdrawal wells. Finally, the FAAIO required Peoples Gas to develop and implement a Groundwater Management Zone.
Groundwater Management Zone
On August 1, 2019, Peoples Gas submitted an application for a groundwater management zone (“GMZ Application”) to the Illinois EPA for Manlove Field. The GMZ application was submitted pursuant to Section 620.250 of the Illinois Pollution Control Board Regulations, 35 Ill. Adm. Code 620.250, to establish a three-dimensional region containing groundwater that is being managed to mitigate a release of stored natural gas from the Manlove Field. The purpose of the GMZ is to ensure area groundwater impacted by MC2 thermogenic methane gas complies with the requirements of Section 12(a) of the Illinois Environmental Protection Act, 415 ILCS 5/12(a) (2020), and Section 620.301(a)(1) and (2) of the Board Regulations, 35 Ill. Adm. Code 620.301(a)(1) and (2). The cleanup objectives of the GMZ are levels of less than 10 mg/L of MC2 thermogenic methane in all Sentinel Wells, and, for all Monitoring Wells other than Sentinel Wells, levels of either (i) less than 10 mg/L of MC2 thermogenic methane or (ii) asymptotic levels above 10 mg/L and below 28 mg/L of MC2 thermogenic methane.
“Sentinel Wells” is used here to mean a network of ten water supply wells that currently have less than 10 mg/L of MC2 thermogenic methane, and are located near or just outside the identified GMZ boundary. Following Illinois EPA’s review and requests for additional information, which Peoples Gas provided in multiple submissions, on September 25, 2020, Illinois EPA conditionally approved Peoples Gas’s GMZ Application.
- Flaring: flaring of the three existing relief wells (RW-1, RW-2, and RW-3)
- Relief Wells: installation of four gas relief wells with the purpose to vent the trapped gas and reduce the lifespan of the dissolved gas. Peoples Gas has land leases in place at all four of the Illinois EPA approved relief well locations and the four relief wells have been drilled. A Relief Well Installation Report is required to be submitted on the adequacy of the relief wells and any need for an alternative location for any well that is producing no or minimal amounts of natural gas.
- Monitoring and Reporting Protocol: sampling of the groundwater monitoring network includes a minimum of each well sampled for a total of eight samples in the first year, with quarterly thereafter, followed by semi-annual monitoring.
- Fate-and-Transport Model: Peoples Gas shall operate the gas relief system for at least two (2) years, together with the described groundwater monitoring program. Then the operating data and the other hydrogeologic information acquired in this study shall be incorporated into a two-phase fate-and-transport model for free and dissolved gas in groundwater. This model will be utilized by Peoples Gas and Illinois EPA to evaluate the effectiveness of the remedy system and assess alternative scenarios for management of the GMZ.
The Consent Order required enhanced reporting requirements of any future releases of thermogenic gas and the prior interim court order required additional investigations under the purview of IDNR.
The Consent Order also requires actions which fall under the purview of IDPH and summarized here:
- Peoples Gas shall continue to maintain the 7 gas/water separators (“Devices”) installed in households whose groundwater supplies have shown concentrations of MC2 thermogenic methane in excess of 10 mg/L (“Existing Device Households”) until completion of post corrective action monitoring.
- Peoples Gas will continue to distribute bottled water on a regular basis to Existing Device Households until completion of post corrective action monitoring.
- Peoples Gas installed residential monitoring and alert devices designed to continuously monitor the methane concentrations of indoor air and alarm if the methane concentrations exceed 12,500 parts per million in the air. Peoples Gas shall provide lodging for the members of any Existing Device Household where a Monitoring Device has alarmed due to methane concentration.
- Peoples Gas shall offer to install a gas/water separator (“Stonehouse Device”), in any Existing Device Household that does not have a Stonehouse Device.
- Relief for Existing Households extends to “Other Impacted Households” which is defined as any household in which Peoples Gas has not installed a Device and testing shows a concentration of MC2 thermogenic methane at or above 10 mg/L in the water supply.
Consent Order Exhibits
Resident inquiries: Barb Lieberoff or 217/524-3038
Media inquiries: Kim Biggs or 217/558-1536
IDPH inquiries: Aaron Martin or 217/785-5886