[1.7.10] Adding chunk data

I am interested in, in my rendering, to store some additional data in a chunk, like "Does it have X?" which would be a boolean for the entire chunk, this is so I can make occurences not happen all too close to one another as I want some distance between them, how would I go about it exacly? I don't want the code for me, just either a tutorial (as I don't know what to search for) or hints on what kind of structures would allow it, if I get something simple that gives me a signal of some sort I love to explore the rest myself!