Oil production at the Horse Hill site in Surrey fell at the end of last year to its second lowest level so far.
Figures released by the Oil & Gas Authority yesterday showed Horse Hill’s monthly production for December 2020 dropped to just under 403m3 or nearly 82 barrels per day (bpd).
This was a fall of more than 16% on the previous month and the lowest monthly total apart from October 2020, when a workover was carried out on the Horse Hill-1 (HH-1) well.
DrillOrDrop has been following production at Horse Hill since its formal approval in March 2020.
The site operator’s parent company, UK Oil & Gas plc (UKOG) said in December 2019, that HH-1 was producing an average daily rate of 301 bpd.
So far, production volumes have never reached this level. They peaked in April, the first full month, at 1,160m3, or 243 bpd. They then fell in six of the following eight months.
In April 2020, Horse Hill was ranked fourth for production in UK onshore oil fields, after Wytch Farm in Dorset, Singleton in West Sussex and Welton in Lincolnshire.
Since then, its ranking has slipped along with production. The latest data puts it in eighth place onshore, overtaken by Beckingham and Glentworth in the East Midlands and Horndean and Stockbridge in Hampshire.
At the start of the October 2020 workover, UKOG looked forward to what it called “the resumption of stable oil production at Horse Hill as soon as possible”.
The completion of work was announced on 5 November 2020 and production optimisation trials were expected to last several months, UKOG said.
We’ll continue to monitor how oil production responds to the workover.
The latest data also shows that the volume of formation water produced at Horse Hill was down in December 2020. It fell to about 34bpd, down 13% from 39bpd in November 2020.
In January 2021, UKOG said it planned to turn the HH-2z production well into a water reinjector. The company said this would save money on taking water offsite by tanker for disposal. It will also help to maximise oil recovery by supporting reservoir pressure, the company said.
Associated gas, most of which is flared at Horse Hill, also fell in December 2020 to nearly 7.5 tonnes, down nearly 27% from 10.2 tonnes in November.