A common theory in ground rod placement is that the ground rod should be placed at a 90 degree angle to the target utility and as far away as possible. In the congestion of the real world this is not usually practical. When attaching to a ground or placing a ground spike, care should be taken to not cross over other utilities. If another utility becomes a return path for the current then distorting signals may be the result, making locating more confusing and less accurate.

If you need to, you can look for other grounding opportunities. Metal road signs or telephone pole stabilizers can offer a good ground. (Be careful when using buried metal fence posts as this can then illuminate the whole fence if it too is metal and cause distortion if you are locating nearby.)