TINMAN: A thriller in Bloomington, MN

Death and danger follow Dr. Gregory McGregor on his quest to find the killers of his friend and mentor, Charles Farnsworth, a wealthy partner in TINMAN, a large heavy-equipment construction company. His journey is joined by Corky Gonzales, Charley's Aspen condo house sitter and friend, when it becomes clear she is also in danger.
The killers' tentacles reach from St. Paul to Denver, to Aspen, to L.A. and finally to the scenic beauty of Alaska.
Are the killers motivated by corporate greed - maybe someone at TINMAN? Did Charley have to be silenced when he discovered that drug cartels were smuggling hundreds of millions of dollars of heroin into the United States hidden in TINMAN's heavy equipment returning from jobs in South America? Could the killers be connected to the Environmental movement opposing the proposed billion-dollar Susitna hydroelectric dam project, which TINMAN is expected to build if the project is approved?
Or could the killers be related to something entirely different? And what is the "nine-digit" surprise Charley said he had found but couldn't discuss over the phone? And how was it all related to the fire-bombing of Greg's house just before he was to leave St. Paul to meet Charley? But the biggest question: why are Greg & Corky even targets?