Hiya!
I’ve set up a couple washing stations for veggies (no sink) in the field using metal shelving from old deconstructed heavy duty “wire”utility shelves.
One is is zip tied to 4 t posts over a small drainage ditch, another attached directly to the fence with zip ties, chain and carabiner clips and a third hung from a tree branch again with zip ties chain and carabiner clips. All are supplied with water via hose and hand held sprayer. Soap, clippers etc are kept in an old mailbox also attached w/zip ties. A dish pan serves if something needs to be submerged otherwise and most often Veggies set on grating and rinsed/scrubbed there. I toss trimmings etc on the ground or in a basket to go directly into the compost there in the field. Clean up is way less than when we used to bring everything up to the barn. Been a few years and have not found the need to modify the set up but it’s simple construction makes changes a snap