Identifying Risks

What is the difference between PP SP 2.2 Identify Project Risk and RSKM SP 2.1 Identify Risks?

What you are asking about is one of the basic differences between Maturity Level 2 (ML 2) and Maturity Level 3 (ML 3). Project Planning (PP) is a ML 2 Process Area (PA) and Risk Management (RSKM) is a ML 3 PA. At ML 2, the project only needs to be able to identify risks and that is what PP Specific Practice (SP) 2.2 addresses. At ML 3, RSKM builds upon the foundation of identifying and tracking risks put in place by PP and Project Monitoring and Control (PMC). RSKM SP 2.1 therefore builds upon PP SP 2.2 by adding more rigor for risk identification. Just read the informative material and sub-practices for both SPs and you will immediately see and understand the difference.