What's the difference between fault tree one and fault tree two?

Construction of the Empire State Building 
Construction of Centennial Olympic Park in Atlanta 
Construction of the Panama Canal 
Deployment of a deep water oil rig (such as the Deepwater Horizon) 
Assembly of the International Space Station 
Launch of the Spirit and Opportunity Mars Rovers 
Identification of the Human Genome Project 
Development of the Boeing 787 Dreamliner

Create a two fault or event trees (or one of each) that would support the exploration of risk for one of the above major construction projects (See Chapter 17, pages 216-220). The fault or event tree should offer at a minimum a listing of potential risks and impacts in the event of two smaller failures. For example, a smaller failure could be the loss of water pressure or a fire in a construction project rather than examining what risk was involved with the collapse of the construction project. 

Write a discussion of risks that supports the fault trees that have been created. Make a separate write up for each of these smaller risks (Your paper should have a general introduction that should introduce the two fault or event trees that will be discussed and then the paper should have a discussion regarding each fault or event tree. The discussion write up regarding the identified risks should be from 3-5 pages in length. Note that this page length is a guideline and if you find that your paper supporting the risk tree is longer, there will be no penalty as the final assignment will need to be from 15-20 pages in length.

Sample outline of typical course project paper part I 
Title Page 
Introduction 
Fault Tree One 
Discussion of Fault Tree One 
Fault Tree Two 
Discussion of Fault Tree Two 
Conclusions 
Works cited