Many Jefferson Elementary Children walk to school.  Wai Nani Way, behind Jefferson Elementary curves into Kaneloa Rd.  In spite of these small kids walking Kaneloa Rd. and crossing Wai Nani Way, Concrete Coring drivers are using a No Parking area in this curve to drop and pick up their hugh roll-off dumpsters.  They come through the curve (and not very slowly) cross the cross walk and then back down the street (Wai Nani Way) again crossing the cross walk to drop these dumpsters.  There is no way they would ever see a small child crossing the cross walk while they are backing up.  They also, block this curve while backing and dropping.  They have dropped as many as 4 of these dumpsters at one time in this No Parking Zone.  This is not a legal drop zone and it is very dangerous to our children.  The company has been advised, a driver indicated no concern, and HPD says they cannot do anything.  If it continues, there is going to be tragedy.