We can use this meta-model to represent various process models.
Once defined, such a model provides the context to describe potential risks.
The occurrence of those risks can then be assessed by referring to the actual project (incarnation of the model).
It should be noted that a process model is by definition a simplification of the real project and as such it allows only for as detailed specification of risks as the elements defined by the model.
However, the process model can be improved to represent better the modeled reality.