The Parque das Conchas development is located in the BC-10 block 75 miles southeast of Vitoria int the Campos Basin, offshore Brazil. Shell is the operator with a 50% equity share, with joint venture partners Petrobras (35%) and ONGC (15%). The current development consists of three hydrostatically pressurized medium to heavy oil reservoirs (Abalone, Ostra and Argonauta B West) in water depths ranging from 5430 ft to 6310 ft (1655 m to 1923 m). One of the key enabling technologies at the heart of the subsea system infrastructure is the mudline boosting system consisting of Modulo de Bombeio or Pumping Unit (MOBO) caisson ESPs installed inside Artificial Lift Manifolds (ALMs) 1) . Oil from the individual subsea wells flows into the MOBO caisson ESPs and from there the ESPs pump the oil up to the floating production, storage and offloading (FPSO) vessel. The ALMs are located approximately 5½ miles (8.85 km) from the FPSO (see Figs. 1 and 2). This paper will describe how the design for these special longlife ESPs was developed, how a stack-up test was performed on land in the US, and how the pumps were deployed in the field. In the second part, the first operations for pulling two of the ESPs are described. The whole assembly consisting of the MOBO, 32-in. caisson and ESP completion was lifted in open water to the rig with a total assembled weight of 169 tons (171.7 metric tons). Figure 1: BC-10 Field layout overview.

Summary The Ursa-Princess Waterflood (UPWF) targets the Lower Yellow sand, the main reservoir in the Mars-Ursa basin in Mississippi Canyon, approximately 60 miles south of the mouth of the Mississippi River in the Gulf of Mexico (GOM). The Lower Yellow sand, a world-class Upper Miocene turbidite reservoir, has been on production in the Ursa and Princess fields since 1999, and has been drawn down nearly to the bubblepoint. The waterflood is intended to increase and stabilize reservoir pressure, and to improve sweep efficiency. To accomplish this, four subsea injectors were designed and constructed to inject treated seawater at 40,000 B/D each for a target life of 30 years. Because the Lower Yellow reservoir was already highly depleted, unique risks were identified in the planned subsea completion operations, to be conducted from a mobile offshore drilling unit (MODU). Seawater, used as a completion fluid, was expected to be up to 4,000 psi overbalanced to the reservoir, depending on the well location. This created the risk of either an uncontrollable fluid-level drop in the marine riser or an extreme impairment to the sandface completion. In order to maintain well control with a fluid level at the surface and still deliver low-skin completions, multiple design and procedural issues needed to be addressed, including the following: Control systems on the rig and riser system to prevent uncontrollable fluid-level drop. Perforating systems to minimize impairment in a highly overbalanced environment without adding undue risk to well control. Pill designs that could both control fluid loss at the sandface and clean up effectively. Downhole completion systems capable of functioning either under very high pressure differentials or against very high loss rates. Development of high-burst screens suited to the use of fluid-loss-control pills as a contingency provision in the event that mechanical fluid-loss devices failed. As more deepwater reservoirs approach depletion, specialized tools and procedures will be required to continue to deliver safe and effective sandface completions from floating rigs. This paper details many of these considerations and summarizes the execution experience and results for one such reservoir.

The Ursa-Princess Waterflood (UPWF) targets the Lower Yellow sand, the main reservoir in the Mars-Ursa basin in Mississippi Canyon, about 60 miles south of the mouth of the Mississippi river in the Gulf of Mexico, USA. The Lower Yellow sand, a world class Upper Miocene turbidite reservoir, has been on production in the Ursa and Princess fields since 1999, and has been drawn down nearly to the bubble point. The waterflood is intended to increase and stabilize reservoir pressure, and to improve sweep efficiency. To accomplish this, four subsea injectors were designed and constructed to inject treated seawater at some 40,000 bbl/day each for a target life of 30 years.As the Lower Yellow reservoir was already highly depleted, unique risks were identified in the planned subsea completion operations, to be conducted from a Mobile Offshore Drilling Unit (MODU). Seawater, used as a completion fluid, was expected to be up to 4000 psi overbalanced to the reservoir, depending on the well location. This created the risk of either uncontrollable fluid level drop in the marine riser or extreme impairment to the sandface completion. In order to maintain well control with a fluid level at the surface and still deliver low skin completions, multiple design and procedural issues needed to be addressed, including:1. Control systems on the rig and riser system to prevent uncontrollable fluid level drop, 2.Perforating systems to minimize impairment in a high overbalance environment without adding undue risk to well control, 3.Pill designs that could both control fluid loss at the sand face and clean up effectively, 4.Downhole completion systems capable of functioning either under very high pressure differentials or against very high loss rates, 5.Development of high burst screens that could withstand pilling in the event mechanical fluid loss devices failed. As more Deepwater reservoirs approach depletion, specialized tools and procedures will be required to continue to deliver safe and effective sandface completions from floating rigs. This paper details many of these considerations, and summarizes the execution experience and results for one such reservoir.