## Facts

- Colorado owned a severed coal mineral estate under land in Weld County; a private party owned the surface estate.
- Colorado leased the coal rights to Jack J. Grynberg, but the coal lease was not recorded in county records.
- The City of Northglenn evaluated the land as a potential wastewater reservoir site and planned test drilling, including a deep hole to determine whether commercially recoverable coal existed.
- Northglenn obtained entry permission from the surface owner only and did not seek consent from the State as mineral owner or from Grynberg as coal lessee; it lacked knowledge of the unrecorded lease.
- Northglenn, through engineers and a drilling contractor, drilled a deep test hole within the leased area and found no commercially recoverable coal.
- Northglenn filed a report with the state engineer describing the drilling and results, making the negative coal information publicly available.
- Grynberg claimed the drilling and public disclosure invaded his mineral leasehold and reduced its value.
- The district court granted summary judgment for defendants, and the court of appeals affirmed, reasoning the recording statute protected defendants who lacked notice of the unrecorded lease.

## Issues

1. Whether a surface estate owner may authorize subsurface drilling or geophysical exploration for minerals when the mineral estate is severed and leased to another.
2. Whether Colorado’s recording statute, § 38-35-109(1), bars an unrecorded mineral lessee’s claims against parties who conducted mineral exploration without notice but did not acquire a property interest.

## Decision

- The Colorado Supreme Court reversed the court of appeals and remanded.
- The Court held the surface owner lacked authority to grant permission for mineral exploration that intrudes on the mineral estate.
- The Court held the recording statute did not shield defendants because they were not purchasers or lienors and acquired no estate or interest in the minerals.

## Legal Principles

- When surface and mineral estates are severed, the mineral estate is dominant for purposes of mineral exploration and development, and the surface owner cannot authorize exploration for the severed minerals.
- Subsurface test drilling undertaken to obtain geological or mineral information can constitute a trespass against the mineral estate (geophysical trespass) if done without authorization from the mineral owner or lessee.
- Colorado’s recording act protects subsequent purchasers and encumbrancers who acquire interests in reliance on the record; it does not protect parties who merely conduct testing activities and acquire no real property interest, even if they lack notice of an unrecorded instrument.
- Regulatory requirements for project approval (including submission of geologic information to the state engineer) do not reallocate private property rights or excuse unauthorized intrusion into a severed mineral estate.

## Conclusion

The court held that consent from a surface owner does not authorize mineral test drilling on a severed mineral estate and that the recording statute does not bar an unrecorded coal lessee’s trespass-based claims against testers who acquired no property interest, requiring further proceedings on the merits.


Grynberg v. City of Northglenn, 739 P.2d 230 (Colo. 1987)