IOG plc today confirmed first gas delivery on 12 June from the Blythe H2 development well into the Saturn Banks reception facilities and Bacton terminal.
RATES
The H2 well was brought onstream in three months and one week from spud date despite delays.
The maximum well test dry gas rate is 22.8 mmscf/d and 280-336 bbl/d condensate at the export pipeline pressure of 1250psi.
Production is currently increasing towards an expected initial maximum rate.
DOWNHOLE VALVE
The company said it was also sending equipment to resolve the apparent downhole mechanical blockage constraining flow reported last week.
Analysis of combined pressure and temperature data suggests that a potential cause for the restriction may be a partially activated downhole valve.
The company intends to flow H2 at initial rates until specialist downhole equipment arrives on the rig within the next two weeks to assess and, if necessary, manually actuate the valve.
The intervention is likely to take up to a week at an estimated incremental cost net to IOG of £500,000.
If successful, the intervention is expected to increase H2 flow rates to the previously guided 30-40 mmscf/d range.
PRODUCTION
Post-intervention, IOG still plans to produce initially only from H2, to flush formation water out of the Saturn Banks pipeline system and reduce associated operational expenditure.
The company reported no faults or fractures encountered in the H2 reservoir section and observed no formation water on testing.
Following a period of shut in to allow the water levels to re-equilibrate, IOG plans to reopen H1 periodically at lower rates to flow gas and condensate with limited water production.