Big thanks to @RandomCanuck for finding a CO2 answer!

This document (https://epdmroofs.org/wp-content/uploads/2021/08/08-ERA-Technical-Bulletin-Overview-of-EPDM-design-option-3.pdf) says standard 60mil* EPDM roofing membrane embodies 6.93kg of CO2/sqft.

So 45mil (1.143mm thick) will be 25% less:
6.93-25% = 5.198 kgCO2/sqft.

I bought a 70ft x 30ft section.
So 2100sqft x 5.198 = 10,915.8 kgC02**

That is equivalent to flying from #YVR to #HKG roundtrip, 13 times. Oooooff. That's a bit of a shocker.

OK, I guess I have some work to do to offset/capture some carbon in this here little pond/pool! The good news is, it will not feature any fish so I am hopeful that it will be, eventually, a carbon-negative operation as long as I plant it chock-full and periodically remove/sequester the compost to avoid methane emissions from decomposition.

*WHAT A STUPID MEASUREMENT lol “60mil” = 0.060in or 1.524mm thickness

** Holy heck I love the built-in math in the latest macOS/iOS update!!
#Ponds #Liner #CarbonFootprint #Rubber #BackyardProject #PoolPond

Here's some info I found from Dow on a new process they say *reduces* various polluting factors by ____% but of course they don't give absolute numbers because then we would have actual information.

https://www.dow.com/en-us/document-viewer.html?randomVar=5770251429220267360&docPath=/content/dam/dcc/documents/265/265-15001-01-rubber-industry-trends-poster.pdf