Minami-Senju hosts a very large train freight depot. The Shioiri Park area lies just beside it, and the entire area, including all of the residences (mostly high-rise condos), are very new. I don't know what the area was before, but its 'renewal' is very impressive.
I recommend this park for those who want some wide-open space, but don't want to travel very far to find it!
The park is a short walk or bus ride from Minami-Senju Station. There is also reasonably priced parking available.
By the way, keep your eye out for English language tourist brochures of Arakawa Ward. They are excellent. I would never have know about this park if I hadn't read about it in their brochure.