Andrew, the thing with putting the low voltage line (Ethernet) in the same conduit as high voltage is that it's not kosher with code. Even if you discount potential crosstalk, an inadvertent short between them due to unforeseen circumstances could be deadly. A separate conduit is required for parallel low and high voltage for that reason.
OP, given the soil conditions you describe, I find it amazing that you were able to do a 50' long trench of sufficient depth for high voltage lines in the short time you accomplished it....with a pick-axe.
Last edited by Jim Becker; 10-28-2019 at 9:56 AM.
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The most expensive tool is the one you buy "cheaply" and often...