Waste your operations generate is Scope 3, Category 5. What matters is the material and where it ended up, not the weight alone.
What you need
Two things per waste stream:
Material type. General waste, mixed recycling, paper and cardboard, organics, timber, metal, hazardous, and so on.
Disposal route. Landfill, recycling, composting, waste to energy, or incineration.
A tonne of paper recycled and a tonne of general waste to landfill have very different factors. Weight alone is not enough.
Get it from your contractor
Your waste contractor holds this. Ask for a report by site, by material, by disposal route, in tonnes, for the period.
Most can produce it. If they give you bin lifts rather than weights, ask for their conversion factors.
If you have several contractors across sites, ask each. Do not assume the same mix applies everywhere.
If you only have spend
Use a spend-based factor and record that you did.
Waste is one of the better categories to move to activity data, because contractors generally have it. If you are on spend this year, ask for weights for next year.
Distance to the disposal site
The transport of waste to its destination is a separate question from the treatment of the waste.
Most frameworks include the treatment in Category 5 and treat the transport as either included in the waste factor or as Category 4. Check what your factor covers before you add transport separately, or you will double count.
If your contractor gives you kilometres travelled, ask whether their emissions figure already includes it.
Waste to energy
Waste burned to generate electricity is treated differently from waste burned without recovery, and differently again from landfill.
Some suppliers, particularly outside Australia, treat waste to energy as a renewable source. That is their framing for their own energy, and it does not remove the emissions from your waste. Use a waste to energy factor rather than treating it as recycling.
Water and wastewater
Water supply and wastewater treatment are usually reported under Category 5 or Category 1, depending on your framework.
You need volume. If your water bills show only a dollar amount, ask your retailer for consumption, or estimate from headcount.
Getting it into Avarni
Upload tonnes by material and disposal route against a Method configured for waste.
Use a separate line per material and route combination. A single line of total waste tonnage cannot be factored correctly.
If your data arrives per site, map the site so the waste lands at the right facility.