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Granby. Governor Bill Owens allegedly considered authorizing the National Guard to use either an Apache attack helicopter equipped with a Hellfire missile or a two-man fire team equipped with a Javelin anti-tank missile to destroy the bulldozer. As late as 2011, Governor Owens's staff still vehemently denied considering such a course of action, but since then members of the State Patrol revealed that, to the contrary, the governor did consider authorizing an attack
In addition to writings that he left on the wall of his shed, Heemeyer recorded a number of audio tapes explaining his motivation for the attack. He mailed these to his brother in South Dakota shortly before stepping into his bulldozer. Heemeyer's brother turned the tapes over to the Federal Bureau of Investigation (FBI), who in turn sent them to the Grand County Sheriff's Department. The tapes were released by the Grand County Sheriff's Office on August 31, 2004. The tapes are about 2.5 hours in length.[20] The first recording was made on April 13, 2004. The last recording was made thirteen days before the rampage on May 22.
"God built me for this job," Heemeyer said in the first recording. He also said it was God's plan that he not be married or have a family so that he could be in a position to carry out such an attack. "I think God will bless me to get the machine done, to drive it, to do the stuff that I have to do," he said. "God blessed me in advance for the task that I am about to undertake. It is my duty. God has asked me to do this. It's a cross that I am going to carry and I'm carrying it in God's name."
Investigators later found Heemeyer's handwritten list of targets. According to the police, it included the buildings he destroyed, the local Catholic church (which he did not damage), and the names of various people who had sided against him in past disputes.[22] Notes found by investigators after the incident indicated that the primary motivation for the bulldozer rampage was his plan to stop the concrete plant from being built near his shop. These notes indicated that he held grudges over the zoning approval. "I was always willing to be reasonable until I had to be unreasonable", he wrote. "Sometimes reasonable men must do unreasonable things."