Thinking about a nest burrow?

Thinking about a nest burrow?

Observation - Thinking about a nest burrow? - Southern Africa. Description: Large (c. 40mm body-length) all-black wasp with blue sheen just sitting on foredune between sparse d

Large (c. 40mm body-length) all-black wasp with blue sheen just sitting on foredune between sparse dune veg. Sunning? Contemplating nest site? Noisy take-off.