ENVIRONMENTAL STATEMENT BARDOLINO DEVELOPMENT

Bardolino Development Environmental Statement
3.7 PRODUCTION, UTILITY AND MAINTENANCE OPERATIONS
3.7.1 Bardolino Production Profiles
The Bardolino field will produce gas and oil over an expected field life of 10 years. Figure
3.10 shows the forecasted high case (P10 or 10% likelihood of occurring), base case (P50 or
50% likelihood of occurring) and low case (P90 or 90% likelihood of occurring) production
profiles for Bardolino.
The high case ultimate recovery for production from the Bardolino development well is 11.96
billion scf of gas and 13,253 million bbls of oil. As the reservoir pressure declines throughout
field life the gas oil ratio (GOR) is expected to increase. At the beginning of field life the GOR
is expected to be 870 scf/stb, and this will increase to 1,599 scf/stb at the end of field life.
Figure 3.10: Bardolino development production forecast
Oil production (Mbbls/day)
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3.7.2 Production Operations
Field life (years)
High case oil production
Base case oil production
Low case oil production
High case gas production
Base case gas production
Low case gas production
At present it is anticipated that bringing the Bardolino development on stream may result in
some impacts to the operational performance of the Nelson platform. The addition of
Bardolino fluids through the Nelson process may have an adverse impact on the amounts of
dispersed oil in the produced water discharged at Nelson (discussed further in Section 3.7.3).
In addition, the Bardolino development will increase the volume of the subsea system to
Howe, which will extend the time taken for “blowdown” of the line (de-pressurisation of the
system by venting of gas) when this is required for operational or maintenance reasons.
3.7.3 Produced Water Handling
Oil and gas extracted from North Sea reservoirs can contain substantial quantities of water,
termed produced water. This water can arise from the original formation water, as well as
from water injected into the reservoir to maintain reservoir pressure; the water is then
extracted from the reservoir along with the oil and gas that is removed. Produced water
contains small amounts of natural hydrocarbons, and may also contain traces of dissolved
components such as metals and production chemicals. It must be treated to reduce the
concentration of hydrocarbons to less than 30mg/l before discharge to the sea is permitted.
At the Nelson platform, hydrocyclones and a produced water flash drum are used to separate
produced water from oil and clean it, prior to its re-injection into the reservoir or disposal overboard.
The Nelson platform was required to reduce the quantity of oil discharged to sea to
meet the 2006 Oslo Paris Convention (OSPAR) agreement reductions. Produced Water Re-
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Gas production (MMscf/day)