MADRID, Jan 31 (Reuters) - Korea's group GS Engineering & Construction has hired investment bank Goldman Sachs as an advisor to sell its Spanish water treatment unit Inima, Expansion newspaper reported on Wednesday, citing unidentified market sources.

Inima is worth about 1 billion euros ($1.08 billion), the newspaper said, more than the whole GS & EC's market value, which stood at 1.29 trillion Korean won on Tuesday, according to LSEG data.

The water treatment company booked 90 million euros in earnings before interest, taxes, depreciation and amortization in 2022, Expansion said.

GS E&C bought Inima from Spanish construction group OHLA in 2011 for 231 million euros.

GS E&C, Inima and Goldman Sachs did not immediately respond to requests seeking comment.

($1 = 0.9244 euros) (Reporting by Inti Landauro, Editing by Louise Heavens)