Car wash environmental due diligence: what buyers should check
Modern car washes are fairly clean, but many sit on old gas station lots and all of them send oily water somewhere.
Why car washes carry this risk
A lot that now holds a tunnel wash was often a filling station first. Tanks may have been pulled, or just filled in place.
Wash water carries oil, metals and detergents to an oil-water separator and the sewer. A neglected separator or a past discharge to a ditch is a common finding.
What usually turns up
Former gas station on the lot
Often seriousHistorical aerials and directories often show pump islands decades ago. Old tanks left in place are a known source of later leaks.
Oil-water separator and pits
Worth checkingUnderground pits and separators can crack and leak. Older self-serve bays sometimes drained to dry wells.
Wastewater permit history
Usually minorMost washes discharge to city sewer under a permit. Violations show up in local and sometimes federal records.
What the pre-screen checks for a car wash
- Historical aerials and old maps for a prior filling station or repair shop on the lot.
- State tank lists for removed or abandoned tanks at the address.
- Federal and state discharge and enforcement records.
- Flood zone for the building and equipment room.
Pre-screen a property before you spend on a Phase I
A desk review of one address: past uses from historical photos and maps, federal and state environmental records, and flood risk, ready usually within the hour. $100 for one report, or $100/month for 3.
Questions to ask the seller
- What was on this lot before the car wash?
- Where does wash water go, and when was the separator last cleaned and inspected?
- Any sewer authority notices or fines?
- Do you reclaim water, and are there underground tanks for it?
When to order a full Phase I
Order a full Phase I if the lot was ever a gas station or repair shop, or if bays ever drained to the ground.