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The Alabama Department of Environmental Management (“ADEM”) and Alabama Power Company (“APC”) entered into a January 3rd Consent Order (“CO”) addressing alleged violations of a Major Source Operating Permit (“Permit”).

The CO provides that APC operates a power generation facility (“Facility”) in Mobile County, Alabama.

The Facility is stated to include a coal-fired power boiler operated under the authority of the Permit.

Emission Standard No. 8 of the provisos for the Unit 4 Power Boiler section of the Permit states the following:

The HCl emission rate shall not exceed 0.0020 lb/MMBtu. 40 CFR 63.9991(a)(l)

The CO states that on August 4, 2021, APC performed a HCl emissions test on Unit 4 in accordance with Method 26 of 40 CFR 60, Appendix A.

ADEM is stated to have received an August 30, 2021, report from APC summarizing the results of the previously referenced test. The test is stated to have indicated a measured HCl emissions rate of 0.0023 lb/MMBtu, which exceeded the applicable HCl emissions limit.

APC contends in the CO:

• It operates a powdered dry hydrated line sorbent injection system for acid gas control at Unit 4.
• Because 40 CFR Part 63, Subpart UUUUU also requires control of particulate matter emissions, Unit 4 avoids over-injection of the powdered sorbent, particularly at higher loads. To that end, the Permittee worked diligently with internal and external industry experts to develop an injection rate curve which would define the proper amount of sorbent to inject at a given load in order to effectively control acid gas emissions.
• Less sorbent is needed at lower loads as compared to higher loads to provide the same control efficiency because less fuel is being consumed. In order to provide additional control effectiveness and compliance margin at lower loads, Unit 4 injects relatively higher amounts of sorbent per pound of fuel as compared to higher loads.
• Upon receiving preliminary test results, Unit 4 was taken offline and ADEM was notified of the exceedance and a re-test was scheduled.
• A report summarizing the final results was submitted indicating a measured HCl emissions rate which was well below the applicable HCl emissions limit.
• An investigation was conducted which indicated the control system was operating properly in all respects and consistent with control operations which had previously resulted in compliant stack tests for HCl. (The investigation is also stated to have revealed that constituents in the delivered coal have varied from historic ranges.)
• The previously referenced changes are stated to have upset the balance in Unit 4 and it is likely that operations at lower loads did not result in any exceedance of the applicable HCl limit.
• The injection rate was adjusted to accommodate the wider range of coal constituents and a re-test conducted at full load.

APC neither admits nor denies ADEM’s contentions.

A civil penalty of $75,000 is assessed.

A copy of the CO can be downloaded here.