Uprighting a Tipped Over Nurse Tank

A step by step plan to upright an anhydrous ammonia nurse tank.

Nurse tanks are used to transport anhydrous ammonia fertilizer as a liquid under pressure from the dealer to the customer. Transportation accidents rarely occur when towed down the road, moved from one field to another, or during field applications. The nurse tank itself is made out of thick steel and the valves are protected so if a tank does overturn a release of ammonia seldom occurs.

Below briefly lists procedures to follow when responding to an anhydrous ammonia tank tip over. Please keep in mind that each incident is unique and that the following procedures should only be used as a rough guide.

Preliminary Steps

• Talk with the vehicle driver and ask, How full is the tank? How fast were you going? How did it happen? Was there a release? etc.
• Check wind direction. Redirect local traffic away from tank. Always approach the nurse tank with the wind at your back.
• Check running gear for loose or broken bolts, tire flats, etc. Dig out valves and monitor pressure gauge readings throughout the operation.
• Remember that the float gauge will not operate correctly on an overturned nurse tank.

Off-loading and Hooking Up

• Whenever possible off-load the tank first. Use either the vapor or fill valves. Be aware that the excess flow valves may close shut while off-loading from these two valves. If that occurs the tank may have to be uprighted first and then emptied.
• The withdrawal valve dip tube of an overturned tank will extend into the vapor space and will be useless to remove liquid from.
• A full 1,000 gallon nurse tank will weigh 7,500 pounds. A full 1,500 gallon nurse tank will weight 10,600 pounds. Equipment you select to upright a nurse tank must be able to safely work with such weights.
• Attach chains to nurse tank and around the fork or bucket of tractor. Have a trained, experienced driver operate the tractor while a second person oversees the operation.
• Having the fire department for support is highly recommended.

Uprighting the Nurse Tank

• Slowly raise tank by lifting the fork and at the same time drive the tractor forward.
  NOTE: A wrecker can also upright a tipped nurse tank with the help of a second vehicle. The second vehicle is attached opposite of the wrecker and is used to prevent the tank from falling hard onto the running gear. The truck can be shifted into neutral allowing the operator to ride the brake while the tank pulls the truck backwards.
• Keep raising the fork to upright the tank and then gently lower it onto its running gear.
• Remove chains. Check tank pressure.
• Did anyone check to see if there was enough clearance under those wires? (see pictures)
• Finish removing any residual liquid ammonia.
• Conduct a safety check of the tank and running gear prior to towing away.
• Do not refill the nurse tank until inspected by a Minnesota state official.

Incident Reporting

The Minnesota Department of Agriculture considers a nurse tank involved in an accident as an incident that needs immediate reporting to the Minnesota Duty Officer. These incidents need reporting whether or not an actual release of ammonia occurred. The fact that there is the threat of a release requires immediate reporting of the incident by telephoning 800-422-0798.

Acknowledgements

These photographs were taken in Cottonwood, Minnesota during anhydrous ammonia first responders training courtesy of the Cottonwood Fire Department, Cottonwood Coop, and Regulatory Management and Consulting, Inc., Sioux City, Iowa.