Montara Petroleum
Operator of record for 31 catalogued wells across 3 states. Every well below links to its full registry page.
Filed as: Montara Petroleum · Montara Petroleum Co. · Montara Petroleum Company
At a glance
Montara Petroleum is the operator of record for 31 catalogued U.S. oil & gas wells in 3 states. None is listed as active, 17 (55%) are plugged & abandoned. Its largest concentration is in California, with 27 wells (87% of its portfolio).
Wells operated
31
Active
0
Plugged
17
Orphaned
0
Portfolio by state
| State | Wells |
|---|---|
| California | 27 |
| Illinois | 2 |
| Montana | 2 |
Well mix
- Oil wells
- 20
- Gas wells
- 4
- Shut-in
- 0
- Active share
- 0%
Is this your company?
Claim Montara Petroleum to keep this portfolio accurate — verified operators can correct well statuses and add plugging documentation.
Claim your operator profileWhere does Montara Petroleum operate?
Montara Petroleum's catalogued wells are spread across 3 states: California (27), Illinois (2) and Montana (2). Its 27 California wells are 0.0% of the 242,471 catalogued in that state — its largest share of any state. Counts cover only states whose registries WellCensus has ingested with operator names; wells in Nebraska and Texas (location indexes) and in states without a registry ingest are not yet attributed to any operator.
How many of Montara Petroleum’s wells are active, plugged or orphaned?
0% of Montara Petroleum's catalogued wells are active, 29 percentage points below the national share of 29%. 55% are plugged & abandoned, against 47% nationally. None of the wells filed under this name is flagged as orphaned.
What kinds of wells does Montara Petroleum operate?
By product class, 20 (65%) are oil wells and 4 (13%) gas wells; nationally the shares are 43% and 17%. The deepest of its wells with a published depth is Dejaegher 1-5 in Musselshell, MT at 4,843 ft. The wells listed below sit in Musselshell (MT), Gallatin (IL), Toole (MT), Tulare (CA), Kern (CA) and Ventura (CA). State filings spell the name 3 ways; WellCensus merges exact-normalized spellings only, so subsidiaries and affiliates keep their own pages.
Notable wells operated by Montara Petroleum
| Well | API # / state ID | Status | Type | Location | Operator | Depth |
|---|---|---|---|---|---|---|
| Dejaegher 1-5 | 25-065-21302 | Plugged & abandoned | Other type | Musselshell, MT | Montara Petroleum | 4,843 ft |
| Allen George 1 | 12-059-00626 | Plugged & abandoned | Injection | Gallatin, IL | Montara Petroleum Co. | 2,920 ft |
| Charles Mausey 1 | 12-059-02280 | Plugged & abandoned | Injection | Gallatin, IL | Montara Petroleum Co. | 2,910 ft |
| Johannsen 6 | 25-101-21489 | Plugged & abandoned | Other type | Toole, MT | Montara Petroleum | 1,798 ft |
| Union Seymour 1 | 04-107-00077 | Plugged & abandoned | Gas | Tulare, CA | Montara Petroleum Company | — |
| Daniel 18-A | 04-107-20045 | Plugged & abandoned | Gas | Tulare, CA | Montara Petroleum Company | — |
| ORS Community 3 | 04-029-50278 | Other status | Oil | Kern, CA | Montara Petroleum Company | — |
| Fee 1 | 04-029-37702 | Plugged & abandoned | Oil | Kern, CA | Montara Petroleum Company | — |
| Crestmont-USL 45X-13 | 04-111-20451 | Plugged & abandoned | Other type | Ventura, CA | Montara Petroleum Company | — |
| Quinn 62 | 04-029-50230 | Other status | Oil | Kern, CA | Montara Petroleum Company | — |
| Quinn 63 | 04-029-50229 | Other status | Oil | Kern, CA | Montara Petroleum Company | — |
| Quinn 62 | 04-029-49662 | Other status | Oil | Kern, CA | Montara Petroleum Company | — |
Deepest first where depth is published. See all 31 wells →
Frequently asked questions
How many wells does Montara Petroleum operate?
Montara Petroleum is the operator of record for 31 catalogued oil & gas wells, with the largest concentration in California (27). Only wells in states WellCensus has ingested are counted.
How many of Montara Petroleum's wells are still active?
0 of Montara Petroleum's catalogued wells are active; 17 are plugged & abandoned.
In which states does Montara Petroleum operate wells?
Montara Petroleum is the operator of record for wells in California (27), Illinois (2) and Montana (2).
Does Montara Petroleum operate mostly oil or gas wells?
20 of Montara Petroleum's catalogued wells are oil wells and 4 are gas wells; the rest are injection, service or unclassified wells.
What is Montara Petroleum's deepest well?
Among wells with a published depth, Dejaegher 1-5 in Musselshell, MT is the deepest at 4,843 ft.
Where Montara Petroleum's wells are
About this data
Source: State oil & gas regulator registries (operator of record as filed, exact-normalized across states) plus the USGS United States Documented Orphaned Well Database (2026), as published October 10, 2026 — WellCensus refreshes it monthly. See the methodology for how records are matched, cleaned and scored.
Cite as: WellCensus, “Montara Petroleum — well portfolio”, https://wellcensus.com/operators/montara-petroleum-5461 (data as of October 10, 2026).
Dataset updated . Operator portfolios are resolved from raw state registry filings (exact-normalized names; subsidiaries stay separate).