Subsea actuation system with retrievable position indicator

A subsea actuation system configured to couple to a subsea structure with a valve with a rising valve stem, the rising valve stem including a rotation-to-linear mechanism for operating the valve, the subsea actuation system comprising:

• an interface for receiving rotation input from a separate retrievable actuator, the interface including:
• a cylindrical bucket defining a first opening in an axial direction of the cylindrical bucket, the cylindrical bucket defining an interior and a second opening, the second opening being a through opening in a radial direction with respect to the axial direction, and
• a shaft located within the interior, the shaft for receiving the rotational input from the retrievable actuator, the shaft coupled to the rotation-to-linear mechanism;
• and
• a position indicator, at least a part of the position indicator configured to be positionable at the interface, at least the part of the position indicator configured to be retrievable from the interface, the position indicator configured to indicate an amount of rotational movement of the shaft and thereby a position of the valve, the position indicator including:
• a first part configured for being positionable within the interior of the cylindrical bucket, and
• a second part coupled to the first part through the second opening, the second part configured for being positionable on an outer side of the cylindrical bucket, the second part being retrievable from the outer side of the cylindrical bucket.