You're inserting values for OperationId that is an identity column.

You can turn on identity insert on the table like this so that you can specify your own identity values.

SET IDENTITY_INSERT Table1 ON

INSERT INTO Table1
/*Note the column list is REQUIRED here, not optional*/
            (OperationID,
             OpDescription,
             FilterID)
VALUES      (20,
             'Hierachy Update',
             1)

SET IDENTITY_INSERT Table1 OFF