Aircraft Accident Report

Nurse Tank Failure With Release of Hazardous Materials
Near Calamus, Iowa
April 15, 2003

NTSB Number HZM-04/01
NTIS Number PB2004-917001

Executive Summary: About 11:50 a.m. central daylight time on April 15, 2003, a nonspecification cargo tank used by River Valley Cooperative (River Valley) exclusively for agricultural purposes as a nurse tank split open after being filled with anhydrous ammonia at River Valley’s nurse tank filling facility near Calamus, Iowa. About 1,300 gallons of the poisonous and corrosive gas escaped, seriously injuring two nurse tank loaders, one of whom died from his injuries 9 days after the accident. Equipment repair and replacement costs associated with the accident totaled about $3,100.

The National Transportation Safety Board determines that the probable cause of the sudden failure of the nurse tank at the anhydrous ammonia filling facility near Calamus, Iowa, on April 15, 2003, was inadequate welding and insufficient radiographic inspection during the tank’s manufacture and lack of periodic testing during its service life.

As a result of its investigation of the accident, the Safety Board identified two major safety issues:

As a result of its investigation of this accident, the Safety Board makes safety recommendations to the Research and Special Programs Administration and River Valley.