My two cents ...
I loved the opening scene to this, well done on that.
You will need Supers, at least for when we first go to Daniel's story, you do have the year in the slug line, but I think it will be better as a super. I think you'll only need this the first time we go back too, once we get back to Daniel's story again we will already know what era it is. You do mention that there is a calendar on page 10, but unless that specific date ( August 23rd, 1963) is marked off somehow, we can't tell what date it actually is .... if this is even necessary.
Page 25, I'm not 100% sure on this one, but I think there is a certain way to do phone calls, not sure though ... format wise I mean.
Nitpick here: If that house was really full of contaminated water, wouldn't it be removed?
page 69 typo - I don't think she would've done without you.
page 106 typo Cassie asks " Do you know where Cassie is?"
So ultimately I did enjoy this read, my problems with it are that it takes too long for both stories to finally connect, I know you wanted to build up Cassie's story and provide us with some backstory of Daniel but it takes 50 pages to do this, roughly around page 54 is when both stories finally connect ...and this is when Cassie chooses the book for her assignment, but Daniel's prophetic writing doesn't start effecting Cassie's life until 30 pages later.
This also leads to another issue I have.....everything seems a bit rushed to me in the end, after it's all said and done you roughly have only 20 or so pages left to tell the actual story which is Daniel's story coming true in Cassie's life.
IMO I think you can cut the first few pages of when Cassie is at home with her dad and she gets the acceptance letter, I don't think it's really needed.
Try and shorten up the amount of pages it takes to connect the two stories, perhaps try and cut some of Daniel's pages as well.
All in all this was pretty good,