How to have an Amazon EC2-like environment on my system?
If the project works with cloudera distribution (not with EMR), you can install cloudera and it should be fine. Only corner I can expect as problematic - if s3 was used as a file system.
If the project indeed works against s3 you have two ways:
a) Try to replace s3 to hdfs and all file names / paths, and it should also work fine (if they are hardcoded).
b) Install OpenStack's Swift which is open source alternative to S3 and then try to run Hadoop over it. Disclosure: I am involved in project of running hadoop over Swift. https://github.com/Dazo-org/swift