I could potentially see a completely separate practicum experience for just the summer if it's something you already have experience in, but want to get some extra hours (e.g., doing more evals the same population and context you've previously done to get more hours and integrated reports) or maybe if it's in a research context (e.g., doing data collection and structured patient assessments for baseline before an intervention study), but I agree that I don't really know how you you'd be able to do this if you didn't have experience with the population, setting, measures, and other aspects of that particular site. Assessment might seem more doable as just a summer gig because it would all be one-offs with patients and not necessarily an ongoing relationship, but assessment is also going to be more difficult and complex than running patients through, say, a manualized therapy, especially if you aren't already quite experienced in all the aspects of what you're doing.
