its pretty unclear what a capex GR engineering will calculate....

its pretty unclear what a capex GR engineering will calculate. in my eyes they are pretty reliable.
they will have both eyes at ATC, its EPCM contractor and its study. So i think a capex of 300 to 400 mio usd is realistic. in my own scenario i calculated with the upper range. the 7.5% discount is just for a better comparison with ATC. could be slightly higher. probably between 9 and 10 %.

ramp up year 1=4000, year 2 = 7000, year 3 = 9000, year 4 10000
capex 400 mio usd,
taxrat 30%,
interest 5%

7.5% discount
@ 27.000 usd HPA ,
= NPV of 970 mio usd

@ 32.000 usd
= 1,35 mrd usd

9.5% discount
@ 27.000 usd HPA
= NPV of 720 mio usd

@ 32.000 usd
= 1,04 mrd usd