If you've been spending all your working week looking after your existing workload, and you now have to travel to another site to carry out work, something has got to give.
Either the quality of work done will be lower OR
You will be working longer hours to fulfil the same quality over an additional site plus existing.

If you are on a Salary with fixed hours and you end up working longer for the same money, something has changed.
If you are on hourly rate you will possibly still end up working longer hours and earning more cash of course something has changed again, but depends if your contract says O-T as required or not.

You need to find out EXACTLY how your employer wants you to work in the new setup.
Somewhere in there is an opportunity to "Improve" your earnings.

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