SB1779 amends Section 209(e)(1) of the Clean Air Act (42 U.S.C. 7543(e)(1)) to expand federal preemption over state emissions standards to cover existing locomotives and engines used in locomotives that are engaged in commerce. The bill restructures the statutory list of nonroad engines, clarifies that certain subcategories are ‘‘subject to regulation under this Act,’’ and adds a new subparagraph (C) that bars state standards for locomotives and locomotive engines engaged in providing common-carrier railroad transportation as defined by 49 U.S.C. 10102.
This change removes a source of state-level regulatory variation for emissions from in-use locomotives and shifts the locus of authority to the federal level. For rail carriers, shippers, and multistate operators, the bill aims to create a single national rulebook; for states and communities, it narrows a tool they might otherwise use to address local air quality and health concerns around railyards and rail corridors.
At a Glance
What It Does
The bill modifies 42 U.S.C. 7543(e)(1) to add a new subparagraph (C) that prohibits states from setting standards relating to the control of emissions from existing locomotives and engines used in locomotives that are engaged in commerce. It also edits existing subparagraphs to clarify which small nonroad engines and locomotive-related engines are ‘‘subject to regulation under this Act.’"
Who It Affects
State environmental agencies and legislatures that might otherwise adopt in-use locomotive emissions standards; freight and passenger rail carriers that operate locomotives in interstate commerce; EPA, which retains primary federal authority over locomotive emissions; and communities near railyards that rely on state-level regulation for local air quality controls.
Why It Matters
The bill creates nationwide preemption for a significant slice of rail emissions policy, reducing the risk of a patchwork of state rules but also removing state flexibility to pursue stricter local standards. That shift affects compliance strategy, capital planning for railroads, and how regulators and communities address localized pollution from existing locomotives.
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What This Bill Actually Does
SB1779 is a narrow, text-specific amendment to the Clean Air Act that targets state-level regulation of emissions from existing locomotives and the engines in those locomotives. Its operative move is to change the language of Section 209(e)(1), which governs preemption for certain nonroad engines, so that locomotives and locomotive engines engaged in commerce are expressly included among the engine categories for which states may not set emissions standards.
The bill ties the covered locomotives to the statutory concept of ‘‘commerce’’ by referencing 49 U.S.C. 10102, thereby signaling Congress’s intent to include common-carrier rail operations.
Mechanically, the bill also cleans up the statutory text: it reshapes the enumerated list of nonroad engines (moving from a two-item introductory clause to a three-item list), inserts a legislative confirmation that some subcategories are ‘‘subject to regulation under this Act,’’ and then appends the new subparagraph (C) that does the preemption work. Those drafting moves narrow interpretive disputes about whether certain locomotive-related engines fall inside or outside federal preemption by explicitly tying coverage to engines subject to the Clean Air Act and to commerce-engaged locomotives.The practical effect is to foreclose state attempts to impose their own emissions standards on the in-use fleet of locomotives that operate in commerce (as defined under federal transportation law).
That means state rules aimed specifically at retrofits, operational limits, or performance standards for existing locomotives would be displaced for the subset of locomotives covered. The bill does not itself set federal emission standards or alter EPA’s statutory rulemaking duties under the Clean Air Act; rather, it channels control over this policy area to the federal level by removing a parallel state pathway.Because the amendment is limited in text and scope, it leaves open a number of practical lines of inquiry: how the ‘‘engaged in commerce’’ phrase will be applied to local switching locomotives, privately owned industrial locomotives, and short-line operators; how the change interacts with existing state implementation plans or local permitting programs; and what enforcement mechanisms will be used where state standards are struck down or declared preempted.
Those implementation questions will determine how sharp the policy shift proves to be on the ground.
The Five Things You Need to Know
The bill amends Section 209(e)(1) of the Clean Air Act (42 U.S.C. 7543(e)(1)), adding a new subparagraph (C) to that provision.
New subparagraph (C) bars states from adopting standards ‘‘relating to the control of emissions’’ for locomotives or engines used in locomotives that are engaged in commerce.
The bill explicitly defines the commerce scope by referencing 49 U.S.C. 10102, which the text says ‘‘shall encompass all locomotives engaged in providing common carrier railroad transportation for compensation.’", The amendment also alters subparagraph (A) to add three clarifying clauses (use, horsepower less than 175, and subject to regulation under the Act) and inserts into subparagraph (B) the phrase ‘‘which are subject to regulation under this Act,’’ tightening the statutory cross-reference to EPA authority.
SB1779 does not itself create new federal emission limits for locomotives; it removes a state-level regulatory option and therefore concentrates responsibility for emissions standards at the federal level.
Section-by-Section Breakdown
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Short title
Provides the act's short title: the 'Lifting Overburdensome Commerce Obstructions and Motives Act' or 'LOCOMOTIVES Act.' This is purely nominal but signals the sponsor’s policy framing and is the only place the bill names itself.
Restructure introductory clause of 42 U.S.C. 7543(e)(1)
Rewrites the opening phrasing that introduces the enumerated categories of nonroad engines, changing the grammar from an introductory 'either of the following new nonroad engines' to a neutral 'any of the following nonroad engines or nonroad vehicles.' That edit is technical but matters for statutory construction: it avoids a suggestive 'new' limitation and prepares the statute to carry a separate item for existing locomotives.
Clarify subparagraphs (A) and (B) to tie categories to CAA regulation
Amends subparagraph (A) to list three explicit criteria (use in construction or farm equipment, horsepower under 175, and being 'subject to regulation under this Act') and inserts a parallel 'subject to regulation under this Act' clause into subparagraph (B). Those insertions narrow ambiguity by making statutory coverage contingent on the engines being within EPA’s regulatory ambit under the Clean Air Act, which can affect whether particular engines fall under federal preemption.
Add new subparagraph (C) — preempt state standards for locomotives engaged in commerce
Adds subparagraph (C) to bar states from imposing standards concerning emissions control for locomotives or engines used in locomotives that are 'engaged in commerce.' The provision excludes 'the locomotives and engines described in subparagraph (B),' targeting the remaining in-use locomotive population. By referencing 49 U.S.C. 10102, the bill ties the covered group to common-carrier railroad operations, making federal preemption explicit for those locomotives and thereby removing a potential source of state regulatory divergence.
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Explore Environment in Codify Search →Who Benefits and Who Bears the Cost
Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- Class I freight and intercity passenger rail carriers — gain regulatory uniformity across state lines, reducing compliance complexity and lowering the risk of having to meet multiple, potentially conflicting state in-use locomotive standards.
- Shippers and rail-dependent logistics providers — benefit from predictable operating rules and lower transaction costs associated with a single federal standard rather than a patchwork of state rules that could disrupt routing and equipment deployment.
- Rail equipment lessors and national maintenance providers — obtain clearer national requirements for which locomotives must meet which standards, simplifying fleet management and retrofit planning.
Who Bears the Cost
- State and local environmental agencies — lose a tool to impose stricter local emissions limits on in-use locomotives, constraining their ability to address hot spots and localized air quality issues around railyards.
- Communities near railyards and environmental justice populations — may bear the brunt if federal standards are less stringent or slower to address local concerns, because state-level mitigation pathways will be closed for the covered locomotives.
- Short-line railroads, industrial operators, and smaller carriers whose status under 'engaged in commerce' may be contested — face legal and compliance uncertainty about whether they fall inside the federal preemption and what standards (if any) apply to their in-use locomotives.
Key Issues
The Core Tension
The core tension is between national uniformity for commerce-related rail operations and the ability of states to protect local air quality: the bill resolves uncertainty in favor of a single federal regime, which simplifies compliance for interstate operators but removes state-level flexibility to address local harms — a trade-off with no single technical fix in the statutory text.
Although SB1779 is short, it raises several practical and legal questions that the text does not resolve. First, the bill ties coverage to locomotives 'engaged in commerce' and points to 49 U.S.C. 10102’s definition of common-carrier rail service, but it does not define how that reference applies to switching locomotives, privately owned industrial units, leased units, or short-line operators.
Those operational distinctions will matter for enforcement and for whether any locomotives remain within state regulatory reach.
Second, by expressly conditioning coverage on engines 'subject to regulation under this Act' in the amended subparagraphs, the bill narrows some interpretive disputes but leaves open the relationship between federal preemption and state implementation plans, permitting authorities, and nonregulatory state measures (e.g., procurement policies or diesel idling ordinances). The bill does not create federal emission caps or a timetable for EPA action, so the practical effect depends on subsequent federal rulemaking, agency guidance, or litigation that interprets the new preemption language.
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