Is it possible for an undergraduate to get involved in an independent research project unrelated to his/her concentration?
TL;DR: This is possible, but there are costs and you need to decide whether this is worth your while in the long run.

At the undergraduate level, there is some benefit to you learning about research methods. I find that undergraduate students get a better sense of the breadth and messiness of research methods when actually engaged in a research project. In my view, this experience can take place in a number of fields, although I would prefer that this not be the case. The reason is because the experience of research is much more than the method. Beginning students can pick up research habits that are at odds with the way research is conducted in their own field.

Let me give you an example. A medical student wanted to do a systematic review on health promoting hospital design on patient outcomes. She was interested in a particular approach involving an architectural perspective, so she partnered with the academics from the School of Architecture. Now, systematic reviews are performed quite differently in architecture than in medicine. The systematic review was completed and it was a confusing read because the approach was strange. She submitted it to a medical conference with no luck, but it did get accepted in an architecture conference. Good on her. Still, given that her main academic field is medicine, she has admitted to me that she had found it difficult to unlearn some of the habits she picked up in the research project and wished that she had learned within the field.

In another example, I often have quite a number of research tasks requiring completion and regularly issue invitations to undergraduate students to work with me. These tasks involve clinical contexts -- osteomyelitis, carpal tunnel syndrome, obstructive sleep apnoea -- that may not be relevant to student assistants from the Department of Civil Engineering or the Department of English Literature. I don't reject student volunteers because of their degree, but inform them that the techniques that they will learn may be less relevant to their degrees.

Good luck to you.