Actually, taking it out completely will cause problem. Remember that the entire map is surrounded by a radiation zone but the ground and decorations of that zone are taken from wasteland settings of the biomes.xml and rwgmixer.xml.
What you should do is lower the probability that it will be generated into the map.
open your biomes.xml file and go to the very bottom of the file / find this ;
(my values are changed from the default so this is just an example)
<module name="biomeOutput" type="BiomeIDMapper"> <--- find this... its listed below as well (I've removed some code to save space)
<property name="sourceModule" value="clampOutput"/>
<property name="biomemap0.Name" value="pine_forest"/>
<property name="biomemap0.Range" value="0.2,0.5"/><!-- 3 --><--- look at these
<property name="biomemap1.Name" value="snow"/>
<property name="biomemap1.Range" value="0,0.2"/><!-- 2 --> <--- look at these "biomemap1.Range" value="0,0.2"
<property name="biomemap2.Name" value="wasteland"/>
<property name="biomemap2.Range" value="0.5,0.7"/><!-- 2 --><--- look at these
<property name="biomemap3.Name" value="burnt_forest"/>
<property name="biomemap3.Range" value="0.7,0.9"/><!-- 2 --><--- look at these
<property name="biomemap4.Name" value="desert"/>
<property name="biomemap4.Range" value="0.9,1"/><!--1 --><--- look at these
</module>
<module name="biomeOutput" type="BiomeIDMapper">
<property name="sourceModule" value="clampOutput"/>
<property name="biomemap0.Name" value="pine_forest"/><property name="biomemap0.Range" value="0.2,0.5"/><!-- 3 -->
<property name="biomemap1.Name" value="snow"/><property name="biomemap1.Range" value="0,0.2"/><!-- 2 -->
<property name="biomemap2.Name" value="wasteland"/><property name="biomemap2.Range" value="0.5,0.7"/><!-- 2 -->
<property name="biomemap3.Name" value="burnt_forest"/><property name="biomemap3.Range" value="0.7,0.9"/><!-- 2 -->
<property name="biomemap4.Name" value="desert"/><property name="biomemap4.Range" value="0.9,1"/><!-- 1 -->
</module>
the probability works like a percentage. from 0 up to 1 (like this 0.1= 10%... or 0.45= 45%)
you can only go up to 1 cause 1=100%
if you want finer control, add the extra number, like the 45% example, but its not necessary
be careful with these ratios because you can make world way to easy or way to hard very easily
you can see that I have very little snow and almost no desert but lots of forest and an even distribution of waste and burnt
you must change the settings for both sections because they relate to the different map sizes when you fire up a new game
keep checking back as lots of people here are really good at explaining random world variables
Me, I'm a try it till it breaks kindda guy so I'm always messing with the RWGmixer files (remember to backup obviously)
check out
NitroGen as well. Its a world generator that you have a lot of control over... defiantly check it out