Hi LeedUser, 
We have a project to build a new school including a football field, 3 sports fields, a public plaza, a school bus drop-off and a parking lot. Project registered under LEED V4.
This school project will be completed in several phases:
1st phase: 2021-2022: installation of the synthetic field
2nd phase: 2022-2025: construction of the new school and parking lot
3rd phase: 2025 demolition of the existing school
4th phase: 2026 construction of 3 sports fields, a public square, a school bus drop-off
The existing school is currently on the site and within the LEED boundary and will be demolished after the new school is built. Currently, the existing school is located on the site of the future sports fields, public square and school bus drop-off.
The existing school has asbestos on many of its interior finishes and exterior cladding. To facilitate the client's project management process and to minimize demolition costs, the client wanted to remove the demolition of the existing school from the LEED requirements, but this is not possible in our understanding. The client now wishes to bulldoze the existing school without selective dismantling and decontamination.
Issues :
The existing school is largely contaminated with asbestos (at least about 50 %). As mentioned in the guide, hazardous materials will be excluded from the calculations. But according to the bulldozer demolition method, all materials are likely to be contaminated and will all go to landfill. There is no legal obligation to decontaminate the site with this type of demolition. Once the school is demolished, it will be difficult to quantify which materials were originally contaminated and which were not.
Choice 1: Can we exclude all such contaminated waste from the school?
. choice 2: can we include the contaminated materials?
. choice 3: Which measure of quantity is accepted in LEED? approximate or precise
Should the portion of the original pre-demolition contaminated material be calculated and subtracted to obtain the actual demolition waste calculation? Do you accept a percentage value or a rough calculation?
If not, if you ask for a precise measurement based on weighing (current choice), won't the client have the option of having the contaminated materials removed according to the complex processes in place to be able to weigh them?