Remove all grammatical errors from this text: They concluded that the actual primary causes of the 1986 accident were nothing but the engineering factors, and permanent avoidance of such accidents could only be achieved through more advanced technology development.
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The 1986 accident was caused by a failure of theD12000-10000-10000-10000-10000-10000-10000-10000-10000-10000-10000-10000-10000-10000-