Acid wash a drained plaster pool to remove stains/light scale, managing the structural and hydrostatic risks

Steps

1. Confirm the pool has a functioning hydrostatic relief valve or a plan for active groundwater relief before draining — a high water table can cause a drained shell to pop or float
2. Check with the customer/site for known groundwater issues and consider scheduling during a lower water-table season where relevant
3. Wet the plaster surface and apply a diluted muriatic acid solution in small sections, scrubbing and neutralizing/rinsing before it dries, working top-down
4. Continuously manage acid runoff/rinse water per local discharge rules rather than letting it pool at the drain or discharge untreated to storm drains
5. Limit acid washing to what the plaster thickness can tolerate — it removes a layer of surface material each time, so a pool with limited remaining plaster or prior repeated acid washes may need resurfacing instead
6. Refill promptly after washing/neutralizing rather than leaving the shell empty and exposed longer than necessary