Er, what depth? 15ft max depth
What diameter pipeline? Between 6” and 16” diameter.
What operating fluid, pressure, temperature? Oil and gas, variable conditions.
What operation do you intend doing on the pipeline? Mainly non destructive inspection.
How long a section must be exposed? 10ft max.
Do you "know exactly" where the repair ??? is to be made, or must you expose the pipeline and begin measuring thickness/inspecting metal? I know exactly.
Do you require crane access, or from a barge or a pier or a the shore? Crane access and from a barge.
How long will it be exposed? A few hours until 1 or 2 days.
When a problem happens - What do you plan on doing? Mmmm.
What weather (lake rises? Tide moves? Stationary water in lakes, swamp and marsh.
Hurricane blows through? Spring floods come?) is expected while it is exposed? No
What bottom condition? Mud, rock, sand, water lilies, weeds, barnacles and zebra mussels? Mud and sand mainly.