LESLIE 223

Oil · District 10 · Lease #8403

Operator: HIGHMARK ENERGY OPERATING, LLC

Cum Oil

260k BBL

Cum Gas

846k MCF

casinghead

Wells

2

Production

2011-04 — 2026-04

Peak Month

2011-07

Production History

Cum Oil: 260,429 BBL Cum Gas: 846,356 MCF

RRC production reported through Apr 2026 · recent months incomplete

Decline Curve Analysis

qi

13,741 BBL/mo

Di (annual)

331.0%

b-factor

0.9

EUR

212,985 BBL

R-squared

0.903

type

hyperbolic

Operator History (from monthly production reports)

2022-02 — 2026-07 HIGHMARK ENERGY OPERATING, LLC 54 mo
2011-04 — 2022-01 EOG RESOURCES, INC. 130 mo

Wells (2)

WELL#APIOPERATORPERMITSDEPTHLAST_ISSUED
2HHIGHMARK ENERGY OPERATING, LLC19,0002011-02-14
1HHIGHMARK ENERGY OPERATING, LLC19,0002011-01-25