In not-so-recent poll you called for better waste explanation. So I made this. It has never (yet?) made it to waste-related community report so I am publishing it here first, because there are TONS of waste related questions ever since and I am tired of answering all those questions again and again. Not angry, just tired.

So lets go into it. Save this to your favourite if need be. Ask questions here or on my YT channels.

I will also pin here two of my videos. They take different approach, but can teac you a lot as well and though they will overlap with sections bellow, they may help you as well.

Video 1 - waste setups
Old but still valid in most points. The main benefit of this is showing how waste setups can gradually grow based on researches and needs and though you can read it all in this guide, visual representation is sometimes better. And though setups in this guide are more "neat" and tidy, some roughness is nothing to be ashamed in your builds
https://www.youtube.com/watch?v=TepBsNwxe58&ab_channel=comrade-Sirius

Video 2 - example of waste handling from a 60k population map. I have been an expert at this point and way trying some stuff and you can see how that worked (or not).
https://www.youtube.com/watch?v=G1oKQN70Tpw&ab_channel=comrade-Sirius

Have fun!

Every building has it´s inner stands. You can see those by opening its window and scrolling down. Trash will be deposited here unless the external stand is in range. The icon is important, as small bins need to be taken out by a different type of truck then those big skids.
//various types of bins / skids to be found in different buildings

External stand is usually better for multiple reasons
- they have higher capacity then inner stands
- they will collect trash from all buildings in reach. The limiting distance is 125 m counted by road/path length
- besides small small bins you can sort in them right away, so less load goes into your separation plant. Industries can sort right away, residential areas will do so after refining recycling policies in your research tree.
//visible range for external stands after hovering over it´s icon

Good to know stuff:
- external stands work for all buildings in range without regard for their inner stands type, so a small fire station in an industrial area can and will deposit trash to large skids stands it shares with an adjacent factory, despite it having small bins type one on the inside. This works the other way round as well, but we wouldn't recommend doing it :)

- waste collection stands are on the left side of the menu and they all have a white symbol in their icon as well. There are also waste containers transfer points located on the opposite (right) side of the bar and these serve different purpose (see bellow). Their difference is the fact that they have factory connections (shortcut: FC), don´t have any white symbol in their icon and most importantly ARE NOT SERVED by technical services (shortcut: TS).
//left and middle icon have white symbol, TS will collect from them. Right one has FCs and no white symbol and thus is a container transfer - only lines and DOs will go there

- external stands, as well as buildings, that have road access can be added on a line and if you love micromanagement, you absolutely can have a dedicated truck emptying these without using a TS for the job. Yes, TS is much more convenient, but the option is there and for larger waste producers (mines, refineries, chemical plant, …) it is not unwise to add a truck or two on a line with “wait until loaded” checked between factory/stands and waste processing building.
- buildings dealing with waste in their processing CANNOT be served by TS; currently it is composting plant (biowaste), general separation (mixed waste), small and big incinerator and a hazmat treatment and collection via lines/DOs is the only way (DO = distribution office)

Most of you know how TS works, so just a few points here - whenever a small stand is filled to 50% or big stand to 1 full 6,5t container, it sends a signal to TS in range to arrange a pickup. If a TS has a free truck of corresponding type, it answers the call. If not, it looks at trucks already driving for free capacity - either loaded small enough in case of “small” trucks, or a returning empty 6,5t truck. The reason for quotation marks on small is simple - those trucks can carry up to 10 t of waste, so are more suitable for intra-city collection then skids.

The important note here is that ANY VEHICLE (not only TS, but DOs and emergency vehicles as well) are able to replan/adjust their directions ONLY ON ROAD NODES - it can be an intersection with a path or road to road crossroad, but it needs to be a node (purple dot when buildings is shown there). Having houses in extensive path-only areas is thus not only unrealistic, but also renders automated trucks much less efficient.
// purple dots can be seen i.e. when you have selected the "merge pieces" or "waypoint" tool

Also keep in mind that TS trucks tend to collect either household bins or external stands on their way out, so do not mix these too much and have coverage everywhere. It makes a bigger difference the bigger your city area is.

Last but not least - small truck may be more efficient on paper (and path-connected collection points are absolutely more convenient to place), but many players do not think of them this way. Why? Because they have too many of them and thus they driving long distances to waste processing areas loaded with 1-2t of waste. This is not great and we get you like to have “rather more then less”. But there is a solution:

In many Czech and Slovak cities and their quarters you can find these areas, many times as part of TS areas as well. These serves as places where people can drive in and throw out large stuff they do no longer need - old furniture, white electronics, biowaste, (re)construction waste, paper, plastics, glass … there is a bin for everything including “high-volume” where couches, mirrors, and all other big stuff goes.

You can mimic this ingame. Use a waste-containers transfer (big one for 30 containers) as a dropoff for your TS with small waste trucks. Then add a DO (usually the small one for 5 vehicles is enough) and set it to deliver this content to where you want them, so always a full 6,5t garbage heading outside the city. By placing this at the edge of the city will minimise small trucks driving distance (especially valuable when sorting plastics and metals in residential areas) without much pollution kicking in.

Main benefits are
- extra waste storage when you have problems in your waste processing area (like prolonged machinery replacement in the separation plant)
- smaller fuel consumption while still sorting at source with 100% effectivity (unlike less effective separation plant)
- better view of how much of each waste you produce BEFORE you need to start further processing
- looks cool when you designate each types of sorted waste

Keep in mind that the more full these are, the higher the pollution it creates, so do not place it right next to residential buildings, but 200 m is a perfectly ok distance unless you fill this up to a brim and keep it that way. Full open skids (in BOTH transfers AND open external points) emit small pollution with even one half-full container, while closed bins do not. But that probably has more to do with actual amount of trash capable of accumulating inside.

Another bad news is that while container transfers do have tickbox for "notify when full", they basically never send one for some reason (time of writing February 2025), while open dump tickboxes working as intended. For feedback purposes it makes a huge difference, hence why you will see me using dumps in key areas further down this guide.

Different sources produce different types of waste. Lets go over all types quickly:
1) Mixed waste - overall waste category that has at least one type of general unsortable waste in it, which is
1a) Burnable waste (100% burnable)
1b) Other waste (other waste, reducable to ash)
1c) Ash


Ash is special as it will dissipate on open dumps (not in containers) over time. Every type of waste can be either sorted out and recycled, or burned down to clean ash and let the wind do the rest.

Mixed waste can also contain mixture of other waste types:
2) Biological waste - special type, sortable only on source; can be turned into fertiliser by free decaying on dumps or in composting plant, or burned to ashes
3) Fertiliser - biowaste already turned into fertiliser, unsortable unless on source, burnable
4) Plastic waste - can be sorted out in separation plant and recycled to plastics, but unlike following can be burned down as well
5) Metal scrap - can be sorted out and recycled to steel, cannot be burned down (will pass unchanged through incinerator)
6) Construction waste - can be sorted out and recycled to gravel, cannot be burned down
7) Aluminum scrap - can be sorted and recycled to aluminum, unburnable

Then you have a special category which is
8) Hazardous waste (hazmat in short); that is a mixture of hazardous materials (hazmat) and can contain any waste type from 1-7. If you mix hazardous waste into mixed waste, all the amount will turn into hazardous waste. You can either treat it with chemicals, which turns it into standard mixed waste, or burn it whole, which turns everything inside into ashes and then deal with the mixture afterwards
// exact mixture can be seen by hovering a cursor above any bin

Where and when do these types come from? Good question, comrade! It is not random.
a) construction waste (ConWaste) stands in for mining rubble as well as houses demolitions waste and waste from minerals and ores works. This then emerges at every mining site AND gravel processings: gravel quarry, gravel plant, prefabs plant, chemical plant + coal/iron/bauxite/uranium mines.
//coal mine with it´s pre-sorting bins (quite full due to low amount of trucks in TS)

b) metal scrap emerges from iron and steel processing: iron mill and steel mill, vehicle manufacturing, mech+el. components and electronics factories.
//iron processing stands

c) Aluminum scrap is the odd one here, as nowhere in factory processes it appears, you can obtain this one only via hazmat imports (random consist on each customs) or via plane/helicopters scrapping
d) biowaste is the most common one and as told, can be only sorted out on source. It comes in bulk wherever you work with crops or biomass: woodcutter, sawmill, food factory, distillery, cattle farm as well as chemical plant.
//infinite biowaste source - full cattle range feeding composting plant

e) Hazardous waste comes from processes dealing with oil products, chemicals or infectious materials: refinery, chemical plant, UF6 + nuclear fuel processing, plastics and electronics factory and hospitals. You can always find out due to the building having both types listed in it´s description/window.
//explosives factory uses wood, gravel and chemicals as a source = hazmat stand inside

It looks hard and long, but is easy to grasp (wonder what it reminds me of... nevermind).

Let me give you some tips
- Don´t forget to set some of those outer waste stands for hazmat as well where appropriate. Otherwise they won´t put it there
//dedicated stands next to aforementioned explosives factory

- People (workers) will produce biowaste wherever they work (from their food+clothing consumption) as well as some metal scrap and plastics from electronics consumption.

- Tourists and hotels are good money makers, but produce LOTS of waste in return; always place large container stands (6,5t) near hotels
//Hotel Ukraine from first DLC with skins from RiCZrd, you can find his here on workshop

- importing hazardous waste for money can be nice moneymaker, though keep in mind that it´s price depends on it´s consist and by overdoing it you can both raise costs imported parts you pay for (metal scrap, aluscrap, fertiliser, plastic waste) and decrease gains from parts you get paid for (hazmat, ash, mixed waste) to a point that it hardly justify the cost of fuel and vehicle maintenance doing the process

- whenever there is not free space in a specialised container at a stand, the rest of the trash will overflow into mixed waste bins (as observable with those mines shown above in this category)

The backbone of the system is a general separation plant. No matter how good you treat your waste, there is always some that needs sorting anyways - for example the one coming from hospitals as hazardous or when your separating bins were not emptied fast enough and some of it overflowed into mixed waste.

General separation can accept only mixed waste and it is REALLY ADVISABLE to use at least a mid-sized dump as an input building for it. General separation is the only one of the chain that needs not only reconstructions, but also a machinery replacement and at that time it doesn´t work at all, so you need a place for the waste to pile up (and that place better not be your city). Hence aforementioned waste collection yards, which help as well 🙂
Don´t worry about the waste piling high too much, though. A single general separation can comfortably sort a waste from a region of 30-35k people when manned and maintained well.
//general separation and its percentages

General separation works with % of effectivity. For ConWaste it is 65%. This means that when 100 t of construction waste arrives mixed in mixed waste, it gets sorted out as 65 t of construction waste (that is put in export aggregate storage) and remaining 35 t are turned into “other waste”. This might be actually good for you, because from an extensive mining site you effectively dispose of a ⅓ of rubble by burning it, though it creates in turn a lot of ash. You do you.

Two good-to-know thing:
- sorted materials are put into “aggregate” categories, so in a distribution office you need a dumper to truck away ConWaste, or both types of scraps. For sorted out plastics waste you need an open hull.

- as soon as ANY internal export storage fills up, separation stops working. To prevent catastrophes, use a checkbox with “notify when overflowing” on the input dump advised above. This will notify you that something might not be right (standard “notify when production stops” will produce a lot of spam, not good there).

In the menu you can find two specialised separators, one for metal and one for aluminum. They have better percentages then general separation, but sort ONLY their specialised type. In order to use them you would need to chain them in a way of specialised1 -> specialised2 -> general separation (for plastics and conwaste anyway). By sorting at source in major specialised waste type producers (previous chapter) you can easily avoid these two extra buildings, they are not worth it - especially the aluminum one due to basically no source of aluminum scrap. You can use them in non-sorting cases if you'd like to, you have the option.

After getting recyclable resources back, use them. Send biowaste to a composting plant and then deliver to farms or their attached fertiliser dumps, nothing special there.

All recycling has one in common - you hardly need as many people there as the capacity is (often 1 worker is enough) and these are best placed near the major source of their respective waste type. Every steel mill and iron mining and processing site should have a metal recycling plant nearby, as it is much easier for a wasteDO to send a 6,5t there from the city waste yard from time to time than doing it the other way round.
// Steel recycling next to a steel mill, pushing recycled steel into the same open storage as it´s source of metal scrap

Same goes for construction waste recycling. When you are planning your first gravel industry, include this recycling plant. It produces A LOT of it and you will get tons of free gravel extra this way. And every major mining site should have one there or nearby as well.

Plastics are usually not started soon, so it makes sense to have a plastic recycling facility within walking range from the city (350 m from the closest house is enough, 1 worker can walk for sure). With aluminum scrap it is the same, except when you are importing lots of hazmat that includes it - in that case have it closer to the separation plant it processes it.

Few tips
a) when starting with waste on, you cannot build separation right away. But you do not need to, you are given 5 free dumps to store quite some amount of waste. You should be able to research and build general separation before you run out of them

b) if free dumps are not enough, use small concrete dumps. Unlike their bigger sisters these can be built only with an excavator and few tons of material, and by using checkboxes “notify when full” and DO to distribute waste from city waste yard, you can stack them almost infinitely (though keep in mind they emit some pollution).

c) unlike free dumps, free storages are not limited by count, and you can store plastic waste on free open storages placed somewhere aside; same you can do with excess metal scrap or construction waste. These open storages do not take ages to load from like dumps without claws as well, so good for you. I would advise to build gravel recycling right away (or at least it´s input storage if you are about to use one, I don´t see a big advantage of not doing so). Metal/plastic recycling I do after I have around 3 full free storages of materials to be recycled; at that point the recycled materials will render enough materials to pay for it´s building.

d) after you finally have your own general separation, it feels like ages to load waste from open dumps. So don't do it with lines/DOs. Just place/use a free demolition office and assign where it should drop that mixed/hazardous waste and select 5-10 of those to get demolished. It takes much faster to empty them this way ;)

e) general separation has internal garbage bins for workers, but it will overflow to OUTdump after filling itself, so there is no issue in it overflowing after a 1-2 years of usage.

Incinerators are the final destination of the unusable waste generated in your republic. They process everything you feed into them and turn it into ash (if they can). How much ash is created is shown in its effectiveness percentages - burnable waste generates 0% ash (due to 100% effectiveness), while for example burning of fertilizer will generate 70% of the input as ash (only 30% will disappear by burning).
//you can see effectivity in any incinerator. All vanilla incinerator types have the same percentils

There are also 3 things that cannot be burned (outside ash) - metal and aluminum scrap and construction waste. These three will go through unharmed and if you send them there, they will sooner or later clogg any ash dissipation yard you create. This means that in general you do not want to send them there in the first place.

There are two exemptions
1) You operate something I call “pre-incinerator”; while one general separation can handle 30-35k pop region, trucking all waste 3-5 km away might be quite a logistical challenge, especially from something like a refinery, large chemical plant or a steel mill. If you want to transport large amounts of waste over larger distances, best thing to have is a setup of “waste containers transfer -> small incinerator -> rail dump with claws; then you can send a train to load trash there and the pre-incinerator will reduce the amount of waste to about half the amount. Good thing about it is that you are losing only plastics, as rest is unburnable and can be sorted upon arrival to general separation (it is then advisable to have a receiving rail dump directly connected to the general separation via FC. Why use containers as entry-point? You can use this pre-incinerator for both mixed waste and hazardous waste, which is handy especially for uranium, refinery and chemical areas. Yes, burning hazmat creates a lot of pollution, but you do not have it closer to the city than 1000-1500 m, right? RIGHT?
//typical pre-incinerator; this one close to nuclear processing are; still waiting for rails to be done, so trucked away with few skids on a line to closest separation plant´s “INdump”

2) Burning local hazmat as a direct precursor to general separation. (container transfer -> incinerator -> INdump for general separation -> general separation …).
Why would you do that?
While there is a specialised hazmat treatment plant, it is - mildly told - not very useful. It can process a very limited amount of hazmat per day and that processing costs a lot of chemicals. And you do it only for plastic waste. What do I mean? We have established that all other things do not burn at all (scraps, rubble) or cannot be taken out no matter what (biowaste, fertiliser). Plastic waste is the only thing that
a) can be separated, and
b) burns
The problem is that plastics are generally cheaper per ton than chemicals (a bit). Also 10t of plastic waste will be recycled into only 2t of plastics. Even if you imagine a hypothetical mixture of 10% hazmat and 90% plastic waste (which will never happen ingame), it is still CHEAPER to burn it all then waste precious chemicals (let alone erect and maintain a specialised building for it). This building is only usable when you have a VERY limited amount of space to build so you cannot allow a 1 km exclusion zone around your waste processing. Which is rare. Same goes for the wastewater treatment plant, btw ;)

Besides these two cases, standard chain is
Waste transfer -> (pre-)incinerator -> INdump -> gen.separation -> medium dump -> final incinerator -> dump with claw - - - - - - > ash yard
// example of a full chain next a road between two cities 4 km apart. Left to right:
Small container transfer (hazmat, excess biowaste) -> small incinerator -> big dump with claw; these three you can build right away from the start and push all waste generated through them, pick at clawdump and store in free dumps around till rest can be planned and built. Then there is
- general separation in the middle,
- mid-dump for balancing and visual representation that second incinerator is staffed enough and working
- final incinerator (here a small one again, this was starting corner of the map); notice garbage stands for it outside
- large dump with claw again for storing pure ash

As a final incinerator you can pick any one available, preferably a big one. You got three options, each have their problems:
1) small/big standard incinerator; cheapest ones, but unlike others these for some reason produce waste from workers. And this waste is then picked up by ash-distribution lines/DO, which is bad - it will (slowly) fill the ash yard with workers' biowaste. The only counter to this is placing container stands outside and letting TS handle it. Besides this you should be getting pure ash like in the rest of the cases.

2) waste-to-power; an incinerator that creates power by burning waste. Nice addition, though you are not able to run it reliably and it is not too easy to implement it to an existing power grid due to game power pathing mechanics. Best options are therefore to create a parallel local power grid for it or simply hooking it via wires to the nearest customs connection and export anything it creates for your sanity and mental stability.
//sub-terrain view of a steel mill area and waste-to-power in the middle of the picture. You can clearly see separate wiring from it to all substations in the area. Handy that even vanilla ones have multiple connection points now, right? Excess power goes off to the right via big red underground cable directly to nearest customs.

3) waste-to-heat; the most problematic one. It NEEDS to put the heat somewhere to work properly, but is not a good producer at all as well (cannot produce high amounts). It can reliably heat up 1-2 small heat exchangers depending on their load, which is not enough. On the other hand, thanks to this small effectivity you do not need to worry much about it not being able to chew on all of the waste during the year. But waste-to-power is probably a better option; heat cannot be sold in case you have more than you need.


Final step is the ash disposal. Best option is placing an ash yard somewhere near the final incinerator and having the dedicated wasteDO (which you should have anyway for general separation handling) to have 1-2 skid trucks to pick up the (pure) ash from the OUTdump of the final incinerator and deliver it there. You can have single dumps in rows, which will DO serve equally for faster disposal, but let me give you one final trick:
Dumps, like all other storages, behave in a way that when you unload in one, the thing you unload will spread equally into the one you unload in and all directly connected storages as well. This means that you can serve up to 4 dumps from one of them and thus save ¾ of DOslots occupied by this job. Having a double-row of connected dumps arranged in tetris-shapes also looks quite cool. See picture below for reference.
// ash-yard. Undercoloured for better visualisation of what it connected together. Red start dumps are ash dropoff ones.

Hope this will help you in the future, save this for a time you will need it. Because you probably will :)

Be aware that on workshop there are MANY waste related mods, starting from robses mega dumps and ending with various core mechanic chains changing mod collections. They are not a topic for this guide besides one point - many of that was created by guys missing the bigger/whole picture. For example dumps have dissipation level based only partly on their size and it is much better (and easier to place) few medium sized dumps then one humongous.

Everything written and shown in this guide is made purely with vanilla assets. If wou´d ask me, there is not a problem with how things work waste related and it is well balanced. Yes, you can start making raw oil from biowaste via mods, but then you are turning a WASTE (cow feces) into a profitable export resource. And waste is not meant to earn money, waste is to add complexity and semi-realistic mechanics (like water and sewage). And I think it should stay this way.

To sum things up:
- waste emerges at it´s source and besides edge cases it always contain more types of waste (valid for both hazmat and "mixed waste")

- you can use any type of skids/bins next to aby building to serve as it´s main waste dropoff and you want to do it; just keep in mind that open skids produce more pollution then closed bins

- use waste yard to avoid garbage trucks doing miles there and back with 1t of waste

- burn hazmat unless rare cases

- always use general separation, screw the specialised ones (not needed)

- be smart about not exporting ash (ash yards are way cheaper)

- use dumps (not transfers!) in separation area, use dumps with claws for faster loading. Tickboxes in them might (and WILL) save you tons of headaches.

Need an example?
In S3 I am at year 1992 and waste processing you see in pictures here was working flawlesly since 1963, last alteration needed was around 1979 in terms of workers needed in the final incinerator.
After years of hasslng with small gravel mill in city nearby I finally replaced it with big gravel processing, which were able to force-full via conveyors enough gravel to local storage and concrete+asphalt+prefabs processing without ever running out. Where is the catch?

The same gravel storage for 1000t is force-fed from gravel recycling plant via conveyor from the other side. And due to more gravel production and not enough construction it´s (vast) storage filled up, then it´s import storage as well = no place for wasteDO to traffic separated construction waste to. So after a year or so its INdump sent notification that it is (finally) full. This notification trigger my inspection, foung a culprit and made me send one dumper on a line to export excess gravel from the recycling plant to export gravel storage (train job).

You know what would happen without it? Nearest city waste yard would fill up soon as well and then the city, resulting in easy 4-5k deaths out of ca 7k citizens before other messages like "not enough workers" would start coming. And death count would easily climb near 10k, as I have a surplus of population and with 5 cities up and running and total of 40k pop on the map there would be no way of me noticing a problem in my first and decades smooth running city...
:)

So, have fun and analyse your misfortunes. They are steps on you way to learn :)

Sirius Czech

Based on comments and other inputs, let me add few more points:

Loading speeds are awful. A train on a dedicated line is a much better option.

They only "problem" is that they prefer mixed waste above any other, so if you would want to sort in source, you need a DO/line to pick up the remaining stuff. This is especially true for mines which produce a lot of construction waste. At this point a general separation will have some work. Advantage? It lets you burn 35% of the conWaste (turns into other waste -> ash) and you only need to deal with the remaining 65%

Best setup - mine->waste transfer->cableway station
Possible setup - mine + external stand/transfer, TS/DO/truck local transport to waste transfer->cableway station
second one will help with transporting sorted con.waste as well, as there is no direct continuous flow of waste from the mine. Usable well in bauxite mining area or big gravel area for cement plant.

Btw you can use ONE cableway line to feed in workers (miners) AND take out trash. They can hang on the same rope. For mines is the usual good ratio around 1:6 (1 waste vagon for 6 workers vagons), at least that is what worked in my setups.

Big containers need roads, small containers do not and thus can fit more nicely. Recent community update (driven by me and RiCZrd) added footpaths to big containers for better industrial connectivity, but that is a cosmetic.

Good thing about "small" trucks is their ability to collect more in one go; biggest ones are up to 10t big, which is more then 6,5t skids. Yes, they need to drive more to fill themselves, but in crisis these are great. Also small stands do not need road nodes so smoother pathing of sidewalks is assured.

On the other hand, road connected containers CAN have lines assigned (both small and big). In industry that is a great pick. On the other hand - in the city, you can absolutely create a "pickup line" where garbage truck will "wait until 15% loaded" and then zoom through the rest of the nighborhood like irl. Seems like a paradise option, but I personally never got to use it so far.

Yes, though only limited and on one single case - importing and burning hazmat (hazardous waste). Viable on ES (Early Start) as well. Keep in mind that sending a 5t truck to load hazmat that is priced at -400 rub/t won´t result in the truck bringin in 2000 rubles in cash in one go. Hazmat is basically a mixed waste with the addition of toxic part on top - and you are not picking the "clean 100% hazmat"; you pick up the mix.

The price of the mix is also determined of its consist. Generally >30% hazmar in it is good, while lower amount are meaning less profitable trips. Also the more metal and aluminum scraps inside you have, the lower the income is, because - as expected - the price is determined by prices of the WHOLE mix. Yes, you can then re-export those parts and get some money back as well as recycle them and use/sell that way, but it is usually cheaper to buy steel/aluminum directly at CH.
People being joyful about more aluminum and metal scraps in the mix so they can earn more later by selling the burnt ash are thus false. They didn´t earn more, they have just gotten much less on the import side.

Keep also in mind that trucks importing hazmat are prone to BOTH inflation mechanics - hazmat will get less earning the more you import, while other parts like scraps will get more expensive the more you import the mix. Optimal result is thus ca 1-2 cars on a direct hazmat import line, not more. It stops being much (or at all) profitable if you overdo it.

There is few of them, some by design, some not:

1) Trains are horrendously slow at both loading and unloading waste at customs. That is by design. You should process your waste to ash in your republic. This also is a nudge to not being too easy to import hazmat by train en-masse.

2) Hazmat import trucks or other in-republic lines can sometimes get a little bit of mixed waste left after all hazmat is unloaded into a dump, thus providing the line not working properly. Adding a third stop into schedule where they can unload the mixed waste helps. If you set it as "unload only", trucks will skip it when no mixed waste will remain, not costing you any extra fuel. This is also valid for all lines outside TS.
Unloading into a waste transfer where both container types are set helps this issue, too.

3) Waste transfer BEFORE the first incinerator (hazmat burning one) can sometimes filter out conwaste or metal screap sometimes from the hazmat or mix trucked in. No idea why. To deal with it, either
- set a waste DO to pick up such sorted mix out (same as they do with general separation)
- ban it entirely by setting the waste transfer manually as partly mixed and partly hazmat, leaving no room for other waste types

4) Dumps have the similar issue, when a little bit of ash with scrap/conwaste is spewn in it in first go, ash might disappear almost immediately (rate is based on area of the dump, not ash amount); this will leave only "specialised" materials in the dump, thus converting it into a "specialised" dump for scraps/conwaste.

Cure: Stop other waste influx (by reversing the FC going in) and send in a truck on a line with "load all" picked. Should help. Alternatively C+H+E cheat mode and delete those fractions on spot (option will appear after cheat mode activation)

Prevention: ALWAYS set your dumps to mixed waste when dealing with ash. This way they won´t be able to turn themselves.

Small trucks can unload into big skids, but they are horribly slow at loading there (hand showelling is slow). Don´t do such lines. Big skids cannot go to small container stands.

Big container skids unload similarly fast when directly in a waste stand, transfer or directly connected road cargo station. They load fast in only transfers and stands directly, they load much slower when in connected cargo station.
Reason: Dumping trash down from a ramp is much faster then showelling it up one ;)

For those who desire to connect these together (looking at you, Bballjo and Honeybadger), make sure you unload FROM the ramp and load in the transfer bellow.

Or, you know, do it as I do and connect two transfers together with FC. Higher capacity and fast loading assured.

Always leave yourself a spare capacity. You want waste facilities to NOT NEED to run on 85%+ capacity, because the less reserve capacity you have, the longer it takes to process any backlog/sudden increase in trash processing (for example from demolishions and such). Be good general secretaries - plan well.