Fugro EMU will carry out the survey using its Fugro Seeker vessel. The survey is planned to take up to two weeks, weather dependent.
SSE issued a notice to mariners on Monday giving details of where the survey will be taking place off the west coast of Scotland.
A spokesperson for SSE said work will begin "in an appropriate weather window" from tomorrow.
The UXO survey is an important stage in the development of an offshore project. Cabling for the 576MW Gwynt y Mor project was slightly delayed in 2014 following the discovery of three World War II bombs at the site in the Irish Sea last February.
In 2013, transmission operator Tennet suffered months of delays after the discovery of a "massive amount of munition" at the 108MW Riffgat offshore project, off the coast of Germany.
Approximately 30 tonnes of explosives were retrieved or disposed of before it was judged safe to lay cables at the site.
A 680-kilogram mine was destroyed in a controlled explosion at SSE's 500MW Greater Gabbard offshore project in 2011.