This bill amends Section 11 of the 1942 Mammoth Cave authorizing statute to do two things: (1) make the statute’s $350,000 ceiling (for acquiring land under that section) adjustable for inflation using the Consumer Price Index published by the Bureau of Labor Statistics, and (2) authorize the Secretary of the Interior to acquire approximately 551.14 acres (and any interests in that land) depicted as a ‘Proposed Addition’ on a May 2025 map for inclusion in Mammoth Cave National Park.
The changes are narrow and technical on their face, but they shift the practical scope of the Park’s boundary and the fiscal framework for acquisition transactions. The inflation indexing raises the statutory payment limit over time; the map‑based addition expands park acreage and expressly allows acquisition of less‑than‑fee interests, which affects what the National Park Service may seek to buy or accept from landowners.
At a Glance
What It Does
The bill amends the statute governing Mammoth Cave to convert a fixed $350,000 cap into an amount adjusted for inflation using the BLS Consumer Price Index, and it adds an express authorization for the Secretary of the Interior to acquire about 551.14 acres (including any interests in land) shown on a specified May 2025 map for inclusion in the park.
Who It Affects
The primary actors affected are the Department of the Interior/National Park Service (as the acquiring agency), current owners of the identified parcels or interests, and state and local governments in Edmonson and Barren Counties where the parcel lies. Conservation organizations, recreation businesses, and nearby communities will see downstream effects from a park boundary change.
Why It Matters
Indexing the statutory purchase cap prevents the dollar limit from eroding in real terms and makes larger acquisitions more administratively feasible without separate statutory increases. The map‑based addition creates a concrete expansion to park acreage and clarifies that the NPS may acquire fee and non‑fee interests, which broadens its land‑management options.
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What This Bill Actually Does
The bill makes two limited but consequential edits to the Mammoth Cave authorizing statute. First, it replaces a static $350,000 figure in Section 11 with a dollar amount that will be adjusted for inflation using the Consumer Price Index (CPI) published by the Bureau of Labor Statistics.
That change means the statutory ceiling for transactions governed by that paragraph will rise over time without additional legislation, reducing the need for periodic statutory increases to keep pace with market prices.
Second, the bill authorizes the Secretary of the Interior to acquire roughly 551.14 acres shown as a ‘Proposed Addition’ on a named May 2025 map and to include that land in Mammoth Cave National Park. The authorization explicitly includes “any interests in land,” which covers fee simple title as well as lesser interests such as conservation easements, rights‑of‑way, or other encumbrances the Secretary might purchase or accept.The text ties the acquisition authority to a specific map—identified by number and date—so the legal description of the expansion is map‑based rather than a metes‑and‑bounds description in the bill.
The bill does not specify funding sources or acquisition method; acquisition would proceed under existing NPS authority and funding processes (e.g., Land and Water Conservation Fund, appropriations, donations, or agreements with willing sellers) unless and until Congress provides a separate appropriation or the NPS uses funds already available.Operationally, the expansion would require mapping, surveying, title work, and negotiation with landowners or holders of interests. Once acquired, the lands would be managed under park rules and federal land management policies.
Because the statute allows acquisition of interests in land, the NPS could pursue partial interests when fee acquisition is impractical or undesirable, giving the agency flexibility to secure conservation outcomes while leaving some private ownership intact.
The Five Things You Need to Know
The bill amends Section 11 of the Act of June 5, 1942 to make the $350,000 figure 'adjusted for inflation in accordance with the Consumer Price Index published by the Bureau of Labor Statistics of the Department of Labor.', It authorizes the Secretary of the Interior to acquire approximately 551.14 acres depicted as 'Proposed Addition' on the map titled 'Mammoth Cave National Park Proposed Southern Boundary Expansion Edmonson and Barren Counties, Kentucky' (map no. 135/177,967, dated May 2025).
The acquisition authority explicitly covers 'any interests in land,' which permits the Secretary to obtain fee simple title or lesser property interests (for example, easements or other encumbrances).
The bill ties the expansion to a specific map and map number rather than inserting a textual land description into the statute; the map establishes the legal footprint the Secretary may acquire.
The text authorizes acquisition but does not itself appropriate funds or specify an acquisition method, so purchases would rely on existing NPS authorities and funding mechanisms or future appropriations.
Section-by-Section Breakdown
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Short title
Provides the act’s popular name: 'Mammoth Cave National Park Boundary Adjustment Act of 2025.' This is a standard placement and has no operational effect beyond naming; it signals the bill's limited scope to adjust park boundary and acquisition authority.
Makes the $350,000 figure inflation‑adjustable
This provision inserts parenthetical language turning a fixed $350,000 figure into an amount adjusted for inflation using the Consumer Price Index (CPI) published by the Bureau of Labor Statistics. Practically, the change preserves the purchasing power of the statutory ceiling over time. It does not define the base year adjustment mechanism (for example, whether to round, when adjustments take effect each year), so the implementing agency will apply standard CPI indexing practices unless further guidance or regulation narrows the method.
Authorizes acquisition of approximately 551.14 acres shown on a May 2025 map
The bill adds express statutory authority for the Secretary to acquire the parcel depicted as 'Proposed Addition' on a specific May 2025 map and to include that land in Mammoth Cave National Park. By authorizing acquisition of 'approximately 551.14 acres' and 'any interests in land,' the provision delegates discretion to the Secretary to determine precise acreage and to acquire full or partial interests (e.g., easements). The map reference creates a legal anchor for the boundary change; however, it also makes the addition dependent on accurate mapping, surveying, and title work before those acres become federal parkland.
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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
- National Park Service/Department of the Interior — Gains statutory authority to expand park boundaries and greater flexibility to secure conservation outcomes by acquiring fee or non‑fee interests, which helps long‑term resource protection and park planning.
- Conservation and recreation organizations — Obtain a clearer pathway to secure protection for the specified land; the NPS’s ability to accept donations or purchase interests can advance regional conservation goals and public access.
- Park visitors and regional tourism businesses — Stand to benefit from an enlarged park footprint and potentially expanded trail, interpretive, or recreational opportunities that can increase visitation and related economic activity in Edmonson and Barren Counties.
Who Bears the Cost
- Federal budget/future appropriations — While the bill authorizes acquisition, it contains no appropriation; acquiring land or interests will require existing NPS funds or future congressional appropriations, creating potential fiscal pressure on land acquisition budgets or competing priorities.
- Private landowners and holders of interests — Owners who sell or grant interests will cede property rights; negotiations may affect sale prices and future land use, and some owners may face loss of development options or changes to the local tax status of land if converted to federal ownership.
- National Park Service operations — Adding acreage increases management responsibilities (visitor services, law enforcement, habitat management), requiring staff time and operating funds to integrate new lands into park plans and budgets.
Key Issues
The Core Tension
The central tension is between conserving additional lands within a national park—using flexible acquisition language and indexation to make purchases feasible—and the fiscal and property‑rights consequences of that approach: enabling easier acquisition and larger statutory purchase capacity advances conservation goals, but it shifts costs to appropriations, creates uncertainty for willing sellers and local governments, and leaves open how much the federal government will pay or how it will obtain interests in the face of competing budget priorities.
The bill leaves several operational details unresolved. It indexes the $350,000 figure to the BLS CPI but does not specify the method (for example, the reference year, rounding rules, or implementation date), so administrative guidance will determine the concrete impact of indexing.
Indexing preserves purchasing power but reduces the need for Congress to revisit the statutory cap, shifting budgetary pressure onto appropriations and the NPS’s land acquisition accounts.
The acquisition authorization is map‑based and broad—'approximately 551.14 acres' and 'any interests in land'—which increases acquisition flexibility but raises implementation questions. The statute authorizes acquisition but says nothing about eminent domain, preferred funding source, or prioritization among willing sellers; in practice, acquisitions will depend on available funds and cooperation from landowners.
The map reference creates potential legal disputes if boundaries differ after survey, and the lack of a textual legal description might complicate title closure or boundary litigations. Finally, expanding park boundaries has predictable local effects—changes in land tax treatment, permitted uses nearby, and management responsibilities—that the bill does not address through transition provisions or local coordination mechanisms.
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