Solo Oil PLC (LON:SOLO), the operator of the Horse Hill-1 oil discovery has informed the Company that the UK Oil and Gas Authority has now granted its consent for the forthcoming HH-1 extended well test program. All other necessary regulatory consents from Surrey County Council , the Environment Agency and the Health and Safety Executive are already in place. Solo holds a 15% interest in HHDL which in turn holds a 65% interest in the HH-1 discovery.
Commencement of the EWT, which is expected shortly, will be announced in due course.
· Planned 150-day EWT is now set to commence on the Horse Hill oil discovery
· All EWT regulatory permissions now in place and operations are fully funded
· EWT follows the successful short-term flow tests in 2016 which achieved an aggregate stable rate of 1,688 barrels of oil per day (“bopd”)
· Planned EWT comprises three separate long-term flow periods of the Portland, Kimmeridge Limestone 4 (“KL4”) and Kimmeridge Limestone 3 (“KL3”) zones
· Program aims to confirm commerciality of the Portland and Kimmeridge Limestone oil discoveries
· If successful the EWT paves the way for first permanent oil production targeted for 2019
· Drilling of an appraisal well, HH-2, as future producer is expected to follow successful flow testing with planning approval and environmental permits for drilling are already in place.
Neil Ritson, Solo’s Chairman, commented:
“We are very pleased that the EWT will now get underway since it is through these tests that we will be able to confirm that commercial production can be achieved from the reservoirs discovered in Horse Hill-1.”
Horse Hill Oil Discovery
The HH-1 Portland sandstone and Kimmeridge Limestone (KL3 and KL4) oil discoveries lie within onshore Weald Basin licences PEDL137 and PEDL246, covering an area of 55 square miles (143 km2) to the north of Gatwick Airport. As reported on 21 March 2016, HH-1 flow tested at a significant commercial aggregate stable dry oil rate of 1,688 barrels of oil per day (“bopd”) from the Portland, KL3 and KL4 reservoir horizons. During the 30-90 hour flow periods from each of the three productive zones no clear indications of any reservoir pressure depletion were observed.
The EWT will comprise a series of three separate test sequences commencing in the Portland followed by the KL4 and the deeper KL3. If time permits a test combining the KL4 and KL3 (a commingled test) may be undertaken. Each test will utilise existing perforated zones from the 2016 test program. The expected duration of the full 2018 program is around 150 days.
Since the 2016 test campaign established commercially viable initial flow rates for each of the Portland, KL4 and KL3 zones, the goal of the 2018 long-term testing program is to confirm that HH-1’s reservoirs are each connected to a commercially viable oil volume, thus enabling a declaration of commerciality to be made.
It is expected that, should the minimum commercial volume threshold be met or exceeded, a declaration of commerciality for each horizon could be made soon after the completion of each testing sequence.
As in 2016, when oil from the Portland flowed at a stable metered rate of 323 bopd over an 8.5 hour period, a linear rod-pump will be utilised to flow Portland oil from around 35 metres of existing perforations located at approximately 615 metres below surface. The 2016 test rates were constrained by the pump’s stroke capacity, therefore the new test will use a larger pump with a capacity of approximately 475 bopd.
Given the currently estimated Portland production costs of around US$20-25 per barrel, the 32 million barrels most likely Portland oil in place calculated by Xodus in 2017, taken together with the good flow rates recorded in 2016, make the Portland a strong candidate for commercial viability. Consequently, subject to a successful test outcome, a Portland commerciality declaration by late summer 2018 is a realistic possibility.
KL3 and KL4 Tests
The planned Kimmeridge program is designed to build upon the knowledge gained in the short stabilised natural flow periods of the 2016 test campaign, which tested at stabilised dry oil rates of 901 bopd and 464 bopd from the KL4 and KL3 zones respectively. These 2016 rates were recorded over short (4-7.5 hour) stabilised flow periods.
The two 2018 long term Kimmeridge tests will utilise existing perforations and will access approximately 30-metre gross reservoir zones in each of the KL3 and KL4 zones, located at approximately 840 and 900 metres below surface respectively. As well as determining the volume of Kimmeridge oil in contact with the wellbore, the testing program is designed to assess whether the Kimmeridge is a single large reservoir where both KL3 and KL4 are connected by natural fractures within the encasing oil generative shales.
The long term Kimmeridge reservoir performance data is expected to provide the necessary data to enable Petroleum Resources Management System compliant Kimmeridge Limestone reserve and resource figures to be estimated at Horse Hill and, by analogy, for the wider Kimmeridge play in te Weald Basin.
Future Drilling and Production Plans
Subject to a successful testing outcome in the Kimmeridge and Portland, an appraisal well (HH-2) is planned to follow the EWT in late 2018/early 2019. The well is expected be drilled as a future Portland production well. Drilling plans include an option to deepen HH-2 to the Kimmeridge to gather core and image log data, together with a possible northwards deviation to further access the adjacent oil bearing Collendean Farm fault block where there is additional significant Portland oil resources.
Similarly, contingent upon EWT success, an HH-1z Kimmeridge side-track is planned in 2019 following integration of HH-1 Kimmeridge production data into a reservoir model and data from any future HH-2 Kimmeridge core. Necessary planning and EA permits for HH-2 and HH-1z are in place.
To achieve its goal of long-term Horse Hill oil production during 2019, HHDL now plans to submit a further production planning application to SCC in summer 2018. This application will seek consent to produce oil initially from HH-1 & 1z, and HH-2, together with further production wells in a second contingent drilling phase.