I understand your situation as I've been in similar quandaries The most concerning aspect of the area is the amount of violent crime that takes place there.
This map is updated regularly and lists the crimes and type of crimes which happen in an area. You click the little numbers and then click them again...and then when the little blue dots appear, you click one and it tells you the types of crime which were committed.
. www.ilivehere.co.uk/crime-statistics-wakefield-castleford.html
So near the shops it's all shoplifting but there are a few streets where there's tonnes of "violent crime' and "Public disorder" etc.
Castleford has a lot of problems....but sometimes, these areas can also be 'ok' to live in but you have to remember that the social issues which are apparent there will be reflected in the school you send your child to eventually.
The children there will be from very troubled backgrounds in some cases.
That doesn't automatically mean a bad school though....check the Ofsteds of each school and especially the one closest to your new potential address.
Remember though that Ofsted reports can change suddenly from year to year.
Consider the flat you'll be moving to (or house)...have you looked at it on Google Maps? Are the other houses in the street well-kept? Or is there a lot of rubbish in the gardens etc?
This will be your community and your child's community...the kids will be her friends and peers.