You have overexposure, overdevelopment, or both.

XTOL is a speed increasing developer, especially if diluted 1:1 (which I
would recommend for slightly better sharpness).

If the shadow areas have too much density, give less exposure.

If the highlights have too much density, cut down on the film development.

Photos taken of snow are often tricky and sometimes require about 25% less
development than normal to cut the contrast down and keep the highlights
(snow) from blowing out. This may need to coupled with increased exposure,
but in your case you may already have enough (or even too much) exposure.

Keep adjusting exposure and development until you get it right for the type
scene you are photographing. Keep detailed notes about your exposure, the
scene contrast, and the development time.

this : http://www.lorenzoborra.it/brescia/gaver_2.html is Delta 100 expose
at 50 (incident light measured)  in XTOL 1+1 my negative is too dense, but
surprise, was printed without problem on grad 2 paper, i think because is
dense but not too cotrasted.