Methane Releases from Septic Tanks and the Frequency of Emptying.
The paper to which I'll refer in this post is this one: Challenges to Accurate Estimation of Methane Emission from Septic Tanks with Long Emptying Intervals Jakpong Moonkawin, Loi T. Huynh, Mariane Y. Schneider, Shigeo Fujii, Shinya Echigo, Lien P. H. Nguyen, Thu-Huong T. Hoang, Hai T. Huynh, and Hidenori Harada Environmental Science & Technology 2023 57 (43), 16575-16584
The paper is open to the public for free reading, but I will briefly excerpt some interesting facts in it below.
Very recently I referred in this space to the issue of the "great unmentionable," septic waste.
Changing the Language We Use About Handling, Well, to Put It Graphically, Shit: Describing Sanitation Systems.
After dangerous fossil fuel (and bioenergy) waste, aka, "air pollution and climate change," septic waste is the second largest waste releated killer on the planet, and is responsible, according to WHO, for about 1.25 million deaths per year.
WHO Sanitation.
The second most prominent greenhouse gas in the atmosphere, after CO2 (about which humanity has chosen effectively to do nothing effective at all) is methane.
I have a septic system on my property, which a few years ago, partially owing to some activities of an unpleasant neighbor, failed, a very expensive and frankly disgusting event. I installed a very modern system utilizing an aerator to replace it.
The paper cited at the outset of this post has some interesting commentary for those of us - apparently the number is rising - who rely on septic systems to handle our household effluent.
From the text:
A septic system is usually constructed in either of the following two ways: (i) with two components, namely, a septic tank and a soil treatment unit (e.g., leach, infiltration, or drain fields) or (ii) with only a septic tank without a soil treatment unit. The septic system of type ii has to be connected to a sewerage for further treatment. However, in low- and middle-income countries, type (ii) septic tanks are frequently found and they are not always connected to sewerage but discharged to open environments. (14,15) In this study, we focused on the septic system of type (ii) which we from here onward call septic tanks. In low- and middle-income countries in Southeast Asia, septic tanks often receive only blackwater (i.e., blackwater septic tanks), while graywater is directly discharged to a combined sewer or a drain channel... (16)
The paper offers interesting statistics and references to them:
Interesting, I think.
I hope you are enjoying your Sunday.
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Feces deposited in the open drys out very quickly and becomes, more or less, inert. Just curious about the process...
I joke, but maybe the planet wasn't meant to hold 8 billion shitting humans. 
There are lots of septic tanks in the county I live in.
AMEN!!!!
Sadly, there are some folks here on DU who don't understand earth's ecology. And therefore, these folks mistakenly think the planet can accommodate unlimited numbers of humans. 
Knowing how to do things & having the political will to do them are two different things. We've seen all over the planet what happens when a species overpopulates & yet we still did it while thinking we're smarter & better than the animals. Maybe this planet could support 8 billion people but not 8 billion people consuming because our economic systems demand that.
I believe in 20-30 years people will be stunned at the physical changes on our planet & the consequential social changes. Maybe our big brain will save us but it seems to me that pride & greed have about done this planet in. Not that Earth won't go on, it just won't be hospitable to us or all the other living things we depend on. Life is a circle, not a hierarchy, but we are still about to get slapped down a few pegs.