Work
digging peat on Hatfield Moor takes place roughly between Easter
and the end of September, but the exact dates are dependant on the
weather.
If you manage to get onto the site then you can probably use your
imagination for what it is possible to do.
One good action which might not be immediately obvious is to fill
in the drainage ditches which criss-cross the site. This makes the
land drain less slowly and preserves the hydrological integrity
of the site. The land eventually drains to the south-east, with
water being removed by two pumping stations, as shown on this drainage
map.
Another map of the moors is below, showing the extent of the workings.
Taking the peat out of the site is a narrow gauge railway track.
This railway is a bit rubbish: it's easy to break and if you manage
to make the trains speed up then they tend to derail.

For more direct action ideas check out:
Road Raging Top
Tips for Wrecking Roadbreaking