<p>It seems unlikely that you can pull it off. Mudd typically only offers minors to their own students who are taking off-campus majors (usually a student who started at Mudd and then wanted to change majors to a less sciency thing). I would imagine that in order to double-major, you’d have to take all of CMC’s core for the Econ, as well as all of Mudd’s very large core for the CS. Talk to Mudd and CMC for the possibility, and come back here asking for advice when you know it can be done. 
You might also want to see if you can do it with Pomona instead of with Mudd - I don’t know Pomona’s policies, but Pomona and Mudd share a lot of their CS degree.</p>
<p>As far as “how is the workload”, well, Mudd is known as a hard school, but I don’t know how hard the CS major is compared to the others.</p>
<p>Good luck!</p>