The Trend Toward Charging for Waste Disposal in Japan

As the standard of living rises, we human beings has have [antecedent is "human beings," so the plural noun] started throwing away much of our garbage.
In many developed countries, the total amount of waste per day surpasses the speed of handling them it [antecedent is "amount," so the singular noun] in garbage disposal plants.
At the this rate, it has been thought that it [unclear antecedent—could be "amount of waste," but also could be "garbage disposal plants"] will be over the capacity of these plants in no more than 50 years.
Then, Consequently, many municipalities started charging sanitation fees to citizens charging citizens sanitation fees.
In many cases, people pay them as the cost of dust garbage [I'm using US English, not sure about usage for UK English] bags, which is are [antecedent is "bags," so the plural noun] designated by each city, to put it out to the nearest garbage station collection site.
There are significant gaps of the in price between cities, so it is there are [refers to "cases," so use the plural noun] also cases that where the bag's price of cities that started measuring of waste is 10 times as much as that of cities that didn't yet cities that have started measuring waste are charging 10 times as much as cities that haven't yet started.

The biggest effect of sanitation fees is that it raises people's awareness of waste.
Some research showed has shown that about 6 out of ten combustible pieces of ["garbage" is a mass noun, so you can't use numbers with it] garbage in a bag from a house includes was recyclable even in Japan, which is [use ", which is," not "that is" here because this is minor information, not major information] that is said to have a high eco-consciousness in among developed nations.

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A negative aspect of an increase the fee is that it can get a problem of littering or illegal dumping more serious.
As a matter of fact, cracking down on them by officers is getting strict: however, there is no end to irresponsible waste disposal not only industrial waste, but also household waste.
Considering the administrative costs, we may have to pay more in near future.