CREATE TABLE table_630 ("Client" TEXT, "Years of Operation" TEXT, "Area of Operation" TEXT, "Country" TEXT, "Services" TEXT)

Whose address of operation was the Echirax Concession?
SELECT "Client" FROM table_630 WHERE "Area of Operation" = 'EchiraX Concession'
SELECT "Client" FROM "table_630" WHERE "Area of Operation" = 'EchiraX Concession'