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Final Amendments to the Standards of Performance for New Stationary Compression Ignition Internal Combustion Engines Located in Remote Areas of Alaska

EPA amended the Standards of Performance for Stationary Compression Ignition (CI) Internal Combustion Engines to provide regulatory relief for owners and operators of stationary CI engines in remote areas of Alaska. This action removes the requirement that new CI engines in remote areas of Alaska must meet the Tier 4 particulate matter (PM) emission standard and replaces it with a requirement that the engines must meet the Tier 3 PM standard. EPA has already revised the rule to remove the requirement for these engines to meet the Tier 4 standards for other pollutants. This action satisfies EPA’s obligation to revise the rule under the recently enacted Alaska Remote Generator Reliability and Protection Act.

Read a pre-publication version of the final rule and a summary fact sheet below.

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