
When entering a new field have a good look around at the boundary hedges and fences. If you see any white posts, or other obvious markers, pay especial attention to them as they mark pipelines. If you see one you should see a second the other side of the field and the pipeline will be directly between the two.
Despite being much deeper than what your detector would normally find due to the size of them you can often detect them. If you start trying to dig one you will waste a lot of time and effort, and become very frustrated ..... and end up with a very big deep hole!
I did a rally a couple of years back and by the end of the day there were about 20 holes in a perfectly straight line across the one field.
If unsure if you have found a genuine target or a pipeline try a short distance away on the line of the pipe, if you get an identical signal then you have found the pipe but if you do not then it could be a good target.
Evan