The metals are removed during the process, before the ash is contained and brought to the landfill. Glass is silica - the same material as beach sand. Beach sand isn't recyclable either but no one seems to object to it. Maybe because it's glass, in the form of beach sand rather than glass, in the form of microparticles of burned sand? The steam and gasses do NOT go into the air. That's the point of a closed system. The steam and gasses go through pipes, becoming energy, and used to power the system.

Incineration Is NOT a Closed System
 

Incineration is not a closed system. FDAQ response is correct. There is some metals recovery by capturing magnetic material but other materials such as glass. aluminum, etc. go to the combustion process and generally become parts of ash going to landfill.
Steam produced in the boilers go to a condensing steam turbine which produces power. The steam is condensed, recovered, treated, and used again in steam generation with some additional external treated Boiler Feedwater..
The gaseous products of combustion are treated to reduce solids by filtration and liquid scrubbing.
The remaining products of combustion are exhausted to the atmosphere. This stack discharge includes CO2, NOx, so2 etc.
I could not find any real specific description of the actual treating at Covanta so I can not guestimate what reductions are made to NOx and SO2. My guess is not much. Reducing NOx requires catalyst beds , precise temperature control, and injecting Ammonia. Removing SO2 requires precise temperature and pH control and using very specific metallurgy to withstand, erosive corrosive water washing conditions of the exhaust gases.

The non combustibles in the garbage stream such as glass and small metal pieces etc. become the material sent to landfill. Any solids recovered in bag filters and water washing are added to the landfill stream.

You stated that the new paper shopping bags at the grocery stores already had insect larvae. That's not what you searched, which was how bags at your home can pick up larvae. Try this search:

do new paper grocery bags carry insect larvae

and get this result:

The system is definitely not closed. Open for input, open for output. Trash/garbage is incinerated (burned), not disintegrated or dematerialized. It isn't magic, just an upgraded fire pit. As a child in L. A., all houses used to have incinerator in the back yard for burning trash. Cleaning out the ash was one of my chores. Lot of smog back then.

California, huh? That explains a lot. My hubby went to school there.

Thank you.
So, during manufacture bugs are less likely, and become more likely after manufacture depending on conditions like heat and moisture during transport and storage.
Fair enough!

"Explains a lot"? Have no idea what that is supposed to mean. That was then (post WWII), this is now.
Assume that "hubby" got a good education.

My hubby was (has passed away now) a very dedicated environmentalist. Sometimes, in his honor, I still do a lot of stuff I wouldn’t do because I don’t think it is justified but I know he would ….

It's unfortunate that there is so much fake news but not everything is fake news. Where do you think 60 million plastic bags go? Have you ever talked with some of the amazing people who help our sick and suffering wildlife? Many of the studies will list where the study was done. Plastic contamination is more of an inconvenient truth than fake news. Microplastics found embedded in tissues of whales and dolphins | ScienceDaily

At this time my goal is to reduce my plastic use since eliminating it is not realistic. Some of my reusable bags are 5 years old. I wipe them out regularly. When I was up North, I bought several reusable bags made from plastic water bottles. That was over a year ago.

I agree. We use biodegradable dog bags which are 1/3 the size of a grocery bag.

The goal is to reduce, not eliminate at this time. It is so easy to keep reusable bags in my car. I am sorry people don't wipe them out but I do. So easy to take an extra minute to clean a reusable bag.

I buy biodegradable dog poop bags.

it's crucial to understand why incinerating plastic is not just ill-advised—it's a potential catastrophe waiting to unfold. The Toxic Truth: Why Burning Plastic Waste Is a Health and Environmental Disaster | Plastics For Change.

Another story to try to scare you, you understand that it doesn’t work on most of us? Some of it is true. And that part I agree with. The problem is the fanaticism that comes across, akin to Stalinist Communism. It just turns off a lot of people. The more you try to explain, and enforce, the more they turn away. A possibly better approach might be to reward “good” behavior. Not sure exactly how yet, but I’m thinking.

Your smartphone is mainly plastic...

Sorry for your loss.
A dedicated environmentalist would put my poor efforts to shame. I always try to consider the long term effects of my choices. For example, I drive a 2015 Tucson (purchased new), limit my travel to little more than absolute necessity, and combine multiple trips whenever possible. My carbon "tiretrack", is less than if I replaced it with a new ev, considering the costs, both financial and environmental. I pull weeds in my yard, I don't poison them or the ground. I have no living children, so it isn't about leaving a better planet for my kids. It's ethics, I guess. Trying to do the right thing as I believe it to be. Do as little harm as possible while still enjoying the last few days. No one person can do it alone.

Yes, but let me try another approach, no matter how good or kind, say Mother Theresa was, had she kept hitting people over the head with her rosary because they weren’t Catholic, she would have turned even the ones who were considering it, away.

I think, that showing by example, as you are doing, is one excellent way to “pave the path” so to speak.

"Biodegradable" is not what you think it is.

1. They don't break down easily in a natural environment.
2. When they do break down (eventually, after many years), they break down into microplastics - the very thing that people are now concerned about.
3. They are not 100% compostable. Only 20% of their makeup has to be compostable. That's why #1 and #2 are true; because 80% of the components that make up the bag will not compost.
4. They produce methane while they are in landfills.
5. They're made with polymerized plastic - which is plastic, which requires fossil fuels to make, exactly the same fossil fuels that normal plastic bags use.

Designed to scare us? Of course! And we should be scared. Scared, as in concerned. Not scared as in mindless panic.
The "fanaticism", as you negatively portray it, is really just folks that recognize a problem that needs fixing and are ready to get to work on it. Those that refuse to recognize the problem or paint the problem as not of importance of requiring immediate action don't want to be bothered by the inconvenience to their lifestyle.
Maybe the reward for "good behavior" you mention could be leaving behind a cleaner, healthier world? Or, maybe you would rather have a cookie? (Just teasing. Please don't be angry)

PS. Just between us, I want the cleaner, healthier world AND a cookie ... chocolate chip.

Plastic is forever!

No, that's not what it is. It's a religious fervor that wants the plebs to give up airline travel and air conditioning, while the elites fly on private jets and live in palaces with private security.

I am happy to recognize the benefit of good stewardship of the planet, and do what I can within reason. These fanatics are not reasonable.

Guess we will have to agree to disagree. And I still maintain that what seems reasonable to one may seem unreasonable to another. Purely subjective, imho.