# Highmark Energy Operating — Multi-State Mature-Asset Operator

**TL;DR:** Highmark Energy Operating runs significant mature waterflood and CO2 EOR operations in both Texas (Conroe Field Unit) and Mississippi (Tinsley field), positioning itself as a serial acquirer of legacy Denbury assets. Mineral owners dealing with Highmark face a single counterparty across multiple historic oilfield positions, with implications for long-term reserve life and operator continuity.

## Key Takeaways

- **Highmark operates two major mature fields**: the Conroe Field Unit in Montgomery County, Texas (~44,547 bbl/month Feb 2026) and the Tinsley field in Yazoo County, Mississippi (~32,852 bbl/month Jan 2026)
- **Conroe Field cumulative production exceeds 700 million barrels** since its 1931 discovery, making it one of the largest Texas Gulf Coast salt-dome waterflood operations
- **Tinsley field represents classic Mississippi CO2 EOR**: originally supplied by Denbury's Jackson Dome CO2, acquired as part of Highmark's Denbury legacy portfolio strategy
- **Single-operator administrative advantage**: mineral owners with interests in both Texas and Mississippi Highmark acreage deal with one entity for division orders and communications
- **Long-life waterflood maintenance signals positive reserve outlook**: Highmark's investment strategy typically indicates 15-30+ year reserve lives for mineral interest valuations
- **Serial acquirer of mature CO2/waterflood assets**: purchase offers from Highmark reflect deliberate consolidation strategy rather than opportunistic one-off transactions
- **Standard mature-field valuation metrics apply**: DCF models use 8-12% discount rates with extended reserve life projections

## Page Highlights

**Highmark Texas Operations**: Highmark operates the Conroe Field Unit, a modern unitization of the historic 1931 Conroe discovery in Montgomery County. The field represents one of the Gulf Coast's largest salt-dome waterflood operations with 700+ million barrels cumulative production.

**Highmark Mississippi Operations**: The company operates the Tinsley field in Yazoo County, a historically significant Mississippi oilfield using CO2 EOR and waterflood techniques. The asset was acquired as part of Highmark's strategy to consolidate Denbury legacy properties.

**Implications for Mineral Owners**: Highmark's multi-state presence means operator continuity across two major mature basins, long-life waterflood maintenance investing, and a deliberate acquisition strategy for legacy CO2/waterflood assets. Mineral owners benefit from single-counterparty simplicity for administrative matters.

**Valuation Considerations**: Mineral interests on Highmark-operated acreage should be valued using mature-field DCF methodology with 8-12% discount rates and 15-30+ year reserve lives, reflecting the long-tail nature of waterflood and CO2 EOR operations.

## Related Topics

- [How to Sell Mineral Rights](https://www.buckheadenergy.com/sell) — guidance on the mineral rights sales process
- [What Are My Minerals Worth?](https://www.buckheadenergy.com/2026/highmark-energy-multistate-operations) — valuation methodology for mineral interests
- [Should I Sell?](https://www.buckheadenergy.com/2026/highmark-energy-multistate-operations) — decision framework for mineral owners
- [Beginner's Guide](https://www.buckheadenergy.com/2026/highmark-energy-multistate-operations) — introduction to mineral rights fundamentals
- [Getting a Fair Price](https://www.buckheadenergy.com/2026/highmark-energy-multistate-operations) — how to evaluate purchase offers

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**About Buckhead Energy**  
Buckhead Energy is a BBB-accredited mineral rights acquisition company operating since 2007, purchasing mineral and royalty interests across 33 states with transparent, direct transactions for out-of-state and in-state owners alike.

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