metal >> the g f r c ceiling system from the beginning of the design were proposed to be gfrc, the gfrc has a weight of about 17 pounds per square foot and from the beginning of the design, our design criteria was that those panels should remain this place in a seismic event. that they should not come down and this is under maximum credible event for the bay area here. that they should not come down or be displaced where they would represent a hazard in the update they designed a system to include a rebound effect if there is a blast below that it pushes the ceiling up and comes back down for if it were above that it suspends the ceiling and there were a number of recommendations made relative to impulses that the framing system that supports the gfrc, should withstand. and that was going to have an impact on the 6-and-a-half million throughout all the systems in the building. we had previously looked at the opportunities of switching to a metal ceiling because of the complexity of the ceiling systems. there was not a significant -- we didn't see a significant or the design team didn't

park, again to reduce the costs through the use of lighter weight, lower cost terms instead of the gfrc that had been originally proposed. we simplified the storefront glazing, at the west end of the transit center in particular to provide, to switch from amulonless glad to amulon glass allowing us to reduce the cost of what is a significant architectal element of the building in the area and volume. we also simplified along with the architect, the floor in the light column, to provide a glass floor at the base of the light column that will continue to allow the light from primary light column to extend into the rail levels and opening up the circulation in the grand hall and reducing the cost from the skylight seating type of feature that had been proposed at that location. in addition to the hard changes that we have made in the construction documents, and we have had the architect as they were required under their contract to incorporate a number of bid alternates, which will provide us with flexibility as we move forward to the award of the individual trade packages to make the deci

we changed the gfrc ceilings to metal, for example. >> i'm fine with that, there is just one particular point on this issue of looking at this design guidance criteria >> that's what i'm referring to. >> to back off from the hundred percent all. that's all. >> i'm not sure, i'm sorry, bob. because you have presented at the last few meetings. i'm not snur we need to go through. >> i'm satisfied with that. >> the question still remabs remains from other directors. you are not the only person asking that question. what makes it's difficult is that we are hearing from one consultant and it's difficult when we don't have a third party entity to show us the analysis of this is what is necessary. >> we heard from urs as the first consultant that did the design guidance criteria, that's consult no. 1, and we had consult no. 2 along with people like kevin