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I see these types of installations where non-electricians are hired to dig trenches and install underground raceways. Many times, these types of street lighting, service lateral, feeder, and branch circuit projects are being done for various city- or state-funded projects. I am sure this specific installation was not inspected, nor were any permits issued for this work. No qualified inspector I know would approve the use of duct tape as a raceway coupling!
A review of the underground installation requirements of 300.5 would be a good place to start. This section of the Code discusses minimum cover requirements, protection from damage, raceway seals, and backfill requirements. In addition, I see no ribbon or marker above this raceway to warn someone of its location.