Lennox Generating Station granted site-specific standards for emissions

Under the Environmental Protection Act (EPA), the Ministry of the Environment, Conservation and Parks (MECP) has approved Ontario Power Generation Inc.’s (OPG) site-specific standard (SSS) application for its Lennox Generating Station. Located on Highway 33 near Bath, Ont., the Lennox Generating Station now has an SSS for sulphur dioxide, nitrogen oxides, and sulphuric acid for a 10-year period.

According to Ontario Regulation 419/05, section 35 (1) of the EPA, an SSS for a contaminant can be set if it is not feasible for the applicant to meet the requirements set out in the EPA for technical or economic reasons, if the difference between the EPA standard and the SSS for the contaminant is the minimum difference necessary to enable the applicant to comply, and if “there is no public interest reason sufficient to require the denial of the request.”

In September 2022, the Canadian Environmental Law Association (CELA) made a submission to the Environmental Registry Ontario (ERO) opposing the SSS. After the recent ruling, CELA said in a news release, “while CELA is disappointed with the approval of the SSS, the MECP did adopt OPG’s recommended action plan.”

The SSS comes with several conditions, including the reduction of emissions of sulphur dioxide, nitrogen oxides, and sulphuric acid associated with periods when the facility uses residual fuel oil.

As well, OPG will install and operate two ministry-approved monitoring stations and a meteorological tower in the areas where higher concentrations of sulphur dioxide are expected. These locations were selected based on modelling and statistical analyses.

A community liaison committee must be created that includes interested local citizens, First Nations representatives, and Public Health representatives to provide timely and transparent information about operations and emissions. The liaison committee must meet at least once a year.

OPG must also notify the ministry and the public when two consecutive five-minute concentrations of sulphur dioxide exceed 530 micrograms per cubic metre or when the one-hour concentration exceeds 320 micrograms per cubic metre, through a notification system established through consultation with the community liaison committee.

OPG must also notify the public and ministry in advance of peak use of residual fuel oil when high emissions of sulphur dioxide and oxides of nitrogen are anticipated and increased community exposures are expected. Monitoring information must be easily accessible to the public on a website.

In its decision, the MECP responded to concerns raised by the public. For example, one concerned citizen had written, “I live within a few kilometres of the Lennox Generating Station and do not want this additional pollution to be allowed. This can directly affect my family’s health.”

MECP responded that the new SSS will require the facility to continuously reduce hourly emission rates from current levels over the duration of the approval. This will be achieved primarily through requirements for the purchase and use of residual fuel oil with a sulphur content no greater than 0.5 per cent (by weight) starting immediately and for the entire duration of the site-specific standard.

In addition, the ministry said it will require a minimum fuel purchase of 50,000 barrels with a fuel sulphur content of 0.5 percent or below before December 31, 2023, to reduce the sulphur content in the short term. 

The ministry further stated that “OPG Lennox has already installed the best available control technology for the oxides of nitrogen.”

MECP admitted that it is true that, when using residual fuel oil, there is the potential that the emissions from OPG Lennox could lead to air concentrations of nitrogen dioxide, sulphuric acid, and sulphur dioxide “that are of health concern” in the immediate area surrounding the station.

However, MECP continued, “This needs to be considered in conjunction with the expected infrequent occurrence of when the facility is using residual fuel oil at maximum rates coinciding with meteorological conditions that may lead to maximum levels of contaminants off-property. Although these occurrences are rare, the ministry is working with OPG Lennox to reduce these emissions and better protect the surrounding community by providing monitoring and notification system through transparent community communication.”

Another concern raised by opponents of the SSS stated, “According to OPG’s records for the Lennox Generating Station, from 2015 to 2019 residual fuel oil was used 45 per cent of the time, and from 2010 to 2020 residual fuel oil was used 49 per cent of the time. Thus, their use of residual fuel oil is commonplace, even though OPG has given reports to the public that their use of it is rare.”

The MECP responded by describing OPG Lennox as a “peaking plant”: that is, one “providing additional electricity to the grid during peak demand situations.” 

Due to this mode of operation, MECP stated, “the facility only operated at 0.5 per cent of its annual capacity in the last 10 years. Out of this 0.5 per cent capacity utilization, the facility used residual fuel oil less than 46 per cent of the time.” Further, MECP’s expectation is that “OPG Lennox will operate at approximately two per cent of capacity in the future due to projected generation shortfalls from other facilities expected to occur in Ontario in 2026.”

MECP also pointed out that “typically, the OPG Lennox Generating Station is the last on and the first off in the Ontario electricity generating system. Most of the time, the plant sits idle at or near a minimum load of 28 megawatts (MW), with the ability to ramp up quickly, if needed.”

“When called upon to operate,” MECP stated, “the station typically operates at less than 200 MW, and occasionally up to 500 MW. Data from 2015-2019 shows that the Lennox Generating Station operated between five and 200 MW for over 95 per cent of the time. The facility is expected to meet Ontario’s air standards during these operating periods when using natural gas or residual fuel oil.”

CELA’s statement “strongly encourage[d]” members of the community to get involved with the liaison committee once it is created, and expressed hope that the conditions implemented by the MECP would “help ensure the highest degree of safeguards for both the surrounding community’s health and the environment.”