Think my kid plays hard in the dirt?

This is his laundry basket after the clothes went into the washer:

This is the washer after his clothes have been cleaned:

To his credit, we have very fine, silty, sandy dirt here.  So fine that the dust penetrates my tennis shoes AND socks and gets between my toes-I hate that feeling!  And that's just me walking around doing outside chores.  He sits in it, lays down face first in it, makes dirt angels with it.  Our septic tank will fill with dirt before anything else at this rate!