Doriemus Plc announce that Horse Hill Developments Limited (“HHDL”), the operator of the HH-1 Kimmeridge Limestone and conventional Portland Sandstone oil discovery near London’s Gatwick international airport, has informed the Company that, following preliminary engineering and economic modelling of the successful Portland Extended Well Test (“EWT”) programme, it now considers the Portland oil field to be commercially viable.

HHDL now targets the start-up of long term Portland oil production in 2019, subject to the grant of necessary regulatory consents. The first future horizontal production well, HH-2, for which planning and Environment Agency consents are in place, is planned to be drilled in early 2019. Key points and further details are summarised below:

Key Points:

• Following analysis of EWT results and economic modelling of HHDL’s and Xodus Group’s (“Xodus”) forecast oil production profiles, HHDL now considers the Portland oil field to be commercially viable. Work is now underway towards a targeted longterm production start-up in 2019.
• HHDL currently envisages the Portland field development plan to consist of up to 3 production wells and up to 2 pressure support wells.
• A planning application for Portland and Kimmeridge field development is nearing completion and is targeted for submission to Surrey County Council (“SCC”) before year-end.
• Xodus’ inhouse modelling has estimated future Portland oil production profiles, based upon observed pressure and volumetric data from the EWT. The modelling also shows that oil recoveries could possibly be up to 45% of connected Oil in Place (best case) subject to the successful establishment and operation of a full voidage replacement pressure support system to be incorporated into the field’s development.
• The Portland field’s first new horizontal production well, HH-2, which has SCC planning and Environment Agency consents, is planned to spud in early 2019 following completion of the Kimmeridge Limestone EWT.
• As reported on 10 September, the HH-2 horizontal well has a targeted* sustainable daily Portland production rate of a best case estimated rate of between 720 to 1,080 bopd, which is 2 to 3 times the calculated* sustainable vertical well rate of 362 bopd derived from the EWT programme.
• Following submission of the planning application, Xodus’ 2018 Portland Competent Persons Report will be updated to include recoverable reserves and net present values of cash flows associated with the envisaged Portland oil field development.

* There can be no guarantee that forecast, targeted or calculated rates of production and recoveries derived from the current and future engineering modelling will be achieved.

David Lenigas, Doriemus’s Executive Chairman, commented:
“The declaration of Portland commercial viability by the operator today is a very significant milestone for the Company. It transforms Horse Hill from solely exploration into a fully-fledged field development with a full-scale oil production start-up targeted in 2019. The better than expected EWT results have shown clearly that the Portland reservoir has significant daily production potential in its own right. We also eagerly anticipate the possibility of combined long-term production from both the Portland and Kimmeridge, an exciting and potentially transformative prospect for the Horse Hill “Gatwick Gusher” oil discovery in the UK’s Weald Basin and for the Company."

Doriemus Plc interest in HH-1
Doriemus owns 10% of HHDL, which owns 65% of the Horse Hill Licences which hosts the HH-1 oil discovery well located in PEDL137 in the UK’s onshore Weald Basin, or a 6.5% attributable interest in the licences.