Appendix B
Cost Calculations Over 150-Year Life Cycle of the GAEP
The assumptions used in calculating the costs of the coverage are as follows:
plastic: replaced every 10 years at a cost of $140,000/sq. mi.
installation: also every 10 years at a cost of $35,000/sq. mi.
monitoring: cost per sq. mi. is $8750, 50% from labor and 50% from
equipment (replaced every 30 years)
maintenance: cost per sq. mi. is $30,000, 65% from equipment (replaced
every 30 years) and 35% from labor
The cost of the plastic cover for coverage installed in year 1 and carried through to year 150 for 1 sq. mi. is as follows:
Plastic $140,000 x 15 replacements = $2,100,000
Installation $ 35,000 x 15 replacements = $ 525,000
Monitoring
Labor $ 4,375 x 150 years = $ 656,250
Equipment $ 4,375 x 5 replacements = $ 21,875
Maintenance
Labor $ 30,000 x 0.35 x 150 years = $1,575,000
Equipment $ 30,000 x 0.65 x 5 replacements = $ 97,500
Total $4,975,625
$4,975,625 x 67,000 sq. mi. = $333 billion for all year 1 coverage at the end of year 150. Divided by the tons of carbon equivalent emissions offset of 19.5 billion gives $17.1/ton.