What is the date construction is completed in Jo Daviess county?
CREATE TABLE "superfund_sites" (
  "cerclis_id" text,
  "county" text,
  "listed" text,
  "construction_completed" text,
  "partially_deleted" text,
  "deleted" text
);
SELECT "construction_completed" FROM "superfund_sites" WHERE "county"='jo daviess';