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Permit and laws
Federal engine rules already apply by law. Amazon’s requested source-wide caps and support-generator limits are proposals until IDEM issues a permit containing enforceable conditions.
Correct permit category
The distinction changes which review steps can accurately be shown for Hobart.
What Amazon requested
An eligible source accepts federally enforceable limits intended to keep potential emissions below Title V major-source thresholds. Amazon’s requested limits remain proposals until IDEM issues a permit containing them.
What should not be borrowed
IDEM’s separate U.S. EPA objection and citizen-petition explanation is for certain Part 70/Title V permits. It should not be presented as Hobart’s current FESOP pathway.
IDEM’s current review table lists public notice: yes and proposed to U.S. EPA: no for a New Source FESOP Minor PSD/Emission Offset review. Review IDEM’s table ↗
Public review in plain English
The public document describes Amazon’s request. It is not a draft or final IDEM permit.
If IDEM publishes a draft, this site will add it as a separate document rather than replacing Amazon’s application.
IDEM says formal written-comment periods are usually 30 days. The official notice controls the actual dates, and IDEM may schedule a hearing when appropriate.
After the public-comment period, IDEM issues a notice stating whether the permit was issued or denied and provides its formal response to comments.
Your role in the review
IDEM says formal written-comment periods are usually 30 days. The future Hobart draft-permit notice will control the exact opening date, deadline, project contact and submission methods.
Hobart is in Lake County, which IDEM includes on its Northwest Indiana public-notice page.
Open official notices ↗Join IDEM’s Interested Parties Mailing List. Provide a complete U.S. mailing address and ask for Amazon Data Services/Hobart or Lake County air-permit notices.
jbrush@idem.IN.gov
(317) 233-0185
Download the draft permit, Technical Support Document and public notice. Submit to the exact IDEM contact, address and deadline printed in that notice.
Read IDEM’s process ↗Useful comment checklist
When the draft appears
Northshore Gen will post the draft permit, Technical Support Document, public notice, permit number, opening and closing dates, IDEM project manager and the notice’s exact submission instructions as a new document version.
If you want a public hearing, follow the hearing-request instructions in the same notice. IDEM decides whether to hold one and may extend the comment period.
Source boundary: the video’s 30-day explanation is consistent with IDEM’s public-participation guidance. Its separate 45-day EPA review and 60-day petition sequence is not used here because the submitted Hobart application requests a FESOP rather than a Title V permit.
Plain context: Indiana’s construction-permit review path for a new source that is below the applicable major-source construction thresholds after enforceable limits.
Hobart relevance: Amazon requests a New Source Minor PSD/Emission Offset construction approval.
Plain context: Allows a source that could otherwise trigger Title V to accept federally enforceable limits that keep its potential emissions below major-source thresholds.
Hobart relevance: The application requests a FESOP and calls the proposed source synthetic minor. IDEM must decide the final conditions.
Plain context: Federal standards covering certified engine tiers, fuel, operation, hour meters and records.
Hobart relevance: The application identifies this rule as applicable to all proposed diesel engines.
Plain context: No federal hourly ceiling for genuine emergency use; generally 100 hours for maintenance/testing and a restricted 50-hour non-emergency subset inside that allowance.
Hobart relevance: Amazon asks for no separate critical-generator hour cap beyond this federal rule, while proposing combined annual emission caps.
Plain context: Requires engines covered by the provision to be equipped with a non-resettable hour meter before startup.
Hobart relevance: The application commits to meters and records showing when and why each engine operated.
Plain context: Federal NESHAP requirements for stationary reciprocating internal-combustion engines.
Hobart relevance: For these new area-source engines, the application says compliance is met through Subpart IIII.
Plain context: Limits sulfur to 15 ppm and includes fuel-quality requirements used by covered engines.
Hobart relevance: The application specifies ULSD or qualifying renewable diesel.
Plain context: Limits visible smoke opacity using specified averaging periods and test methods.
Hobart relevance: The application identifies the Lake County opacity standard and its short-duration allowance.
Plain context: Restricts open burning and dust crossing a property boundary.
Hobart relevance: The application states no routine open burning and no expected fugitive-dust source.
Plain context: Sets particulate concentration limits for qualifying Lake County sources.
Hobart relevance: The application discusses applicability where potential or actual particulate emissions meet the rule’s triggers.
Plain context: Directs qualifying fuel-combustion units that produce heat or power by indirect heat transfer to the particulate formula in section 4.
Hobart relevance: Amazon says the proposed engines do not produce heat or power by indirect heat transfer, so this particular formula would not apply; IDEM reviews that conclusion.
Plain context: Indiana’s CO article includes source categories, standards and exemptions.
Hobart relevance: The application claims an exemption because the generators would be subject to federal CO standards and requested synthetic-minor CO limits. That permit position remains subject to IDEM review.
Plain context: Indiana’s NOx article contains control and trading provisions for specified units and programs.
Hobart relevance: The application concludes that none of the NOx rules in Article 10 applies to the proposed emergency generators. IDEM determines final applicability.
Federal runtime-use buckets
Federal §60.4211(f) does not impose an hourly ceiling while a qualifying emergency exists. The reason for operation must be documented.
Per engine, per year under the federal allowance, subject to the rule’s conditions and recordkeeping.
This is inside—not in addition to—the 100 hours and is permitted only for the limited purposes in the federal rule.
Bridge power is not automatically an emergency.A utility schedule problem does not, by itself, rewrite federal operating categories or create authorization for routine power sales.
Help keep the record current
Send the claim or application page, your supporting source and a short explanation. Corrections are reviewed before publication.