I agree with "J"!
Although I had selected "change the data type to varchar(max)" I removed it as the scenario had stated that no duplicates could be assumed. Therefore, the only proper solution (workaround) to the problem stated was to use UNION ALL -- which, by the way should have used in the first place if the data is not duplicated between the two tables.
A data type change to a table is NOT a "workaround".