Petroleum Product Storage Assessment

Aboveground and underground storage of fuel presents a threat to public health and the environment. Nearly one out of every four underground storage tanks in the United States may now be leaking, according to the U.S. Environmental Protection Agency. If an underground petroleum tank is more than 20 years old, especially if it's not protected against corrosion, the potential for leaking increases dramatically. Newer tanks and piping can also leak if they weren't installed properly.

Even a small gasoline leak of one drop per second can result in the release of about 400 gallons of gasoline into the groundwater in one year. A few quarts of gasoline in the groundwater may be enough to severely pollute a farmstead's drinking water. Low levels of fuel contaminants in water cannot be detected by smell or taste, so seemingly good water may be contaminated to the point of affecting human health.

Preventing tank spills and leaks is especially important because of how rapidly gasoline, diesel, and fuel oil can move through the soil into groundwater. Also, vapors from an underground leak that collect in basements, sumps, or other underground structures have the potential to explode.

The goal of ARKANSAS Farm*A*Syst is to help you protect your drinking water supply.

LOW RISK (rank 4)	LOW-MOD RISK (rank 3)	MOD-HIGH RISK (rank 2)	HIGH RISK (rank 1)	YOUR RANK
LOCATION (all tanks)
• Distance of tank from drinking water well
Tank downslope more than 100 feet from well in medium- or fine-textured soils silt loam, loam, clay loam, clay.	Tank at grade or upslope more than 100 feet from well in medium- or fine-textured soils silt loam, loam, clay loam, clay.	Tank downslope more than 100 feet from well in coarse-textured soil sand, sandy loam.	Tank at grade or upslope less than 100 feet from well in coarse-textured soil sand, sandy loam.
DESIGN AND INSTALLATION (all tanks)
• Type and age of tank
Synthetic tank or tank protected from rust by cathodic protection.	Steel tank less than 15 years old, coated with paint or asphalt.	Coated steel tank 15 or more years old, or bare steel tank less than 15 years old.	Bare steel tank 15 or more years old.
• Spill and overfill protection
Impermeable catch basin plus automatic shutoff.	Impermeable catch basin plus overfill alarm.	Concrete catch pad or diked soil catch basin.	No protection.
• Piping
Piping protected from rust by cathodic protection and sloped back to tank. Check valve at pump (not at tank).	Piping galvanized and sloped back to tank. Check valve at pump.	Piping galvanized and sloped back to tank, but check valve is located at tank (foot valve).	Piping showing rust and corrosion and does not slope back to tank.
• Tank installation
Installed by certified installer.	Installed according to recommendations provided by seller with new tank.	No information on installation.	Installed without backfill, spill containment, anchors and other prescribed protections or by untrained individual.
DESIGN AND INSTALLATION (aboveground tanks only)
• Tank enclosure
Tank surrounded by 6-foot tall metal fence with lock.	Tank surrounded by low fence with lock.	Tank surrounded by low fence. No lock.	No enclosure.
• Secondary containment
Tank placed within concrete or synthetic dike with pad able to hold 125% of tank capacity.	Tank placed within soil dike and pad able to hold 125% of tank capacity.	Tank placed on soil pad, no dike.	No secondary containment.
MONITORING (all tanks)
• Tank testing and leak detection
Regular (monthly) leak monitoring.	Annual tank testing and daily fuel inventory control.	Annual tank testing and occasional fuel inventory control.	No inventory control, testing, or monitoring.
TANK CLOSURE (underground tanks)
• Unused tank
Tank taken from ground and excavation site checked for contamination.	Tank filled with inert material in place and site checked for leaking.	Tank removed or filled with inert material in place and excavation site not checked for contamination or leaking.	Tank left in ground.
		RANKINGS TOTAL (Add up numbers in Your Rank column)
		# OF AREAS RANKED (9 if ranked all)
		Use these two numbers to calculate risk ranking.

Fact Sheet • Risk Ranking

Pictures of chickens, flowers, wheat, a boy looking through a magnifying glass, irrigation pipe, soybean pods, and fruits and vegetables.	Cooperative Extension Service





Cooperative Extension Service	Agricultural Experiment Station
Search \| Publications \| Jobs \| Personnel Directory \| Links County Offices \| Departments