For our best estimate, we assumed it would cost $1.5 million to replace one mile of main, with our lower and upper estimates using $1.2 million per mile and $1.8 million per mile, respectively. The next step were the indirect, safety and social, costs and benefits. Methane lasts for about 12 years in the atmosphere and affects the ozone layer, and it has harmful effects for humans who are exposed to it, which creates a social cost.We calculated the social savings based on emission factors of methane for each pipeline, the social cost of methane, and an estimated time for the length of each leak. Methane leaks can last quite a long time, as the lack of color and odor in methane gas caused them to go unnoticed. Finally, the safety benefits were determined by calculating the money saved by changing the number of leaks at each risk classification, which mostly meant eliminating risk level 4 and 5 leaks. In general, we found the direct replacement costs to be much higher than the indirect savings. This means that while we are indeed saving money in the long run by upgrading, at the time being a lot of money has to be invested in the upgrades, and no one alive right now will live to see the rewards of the …show more content…
As the zone may increase in size due to expansion of a factory, the demand will increase too, raising economic incentives for the natural gas company to want to replace and install lines in this zone. zone B does have a rather mundane set of leaks relative to others, so replacing the leaks would provide some social benefits but not many.
Making any decision to put one zone before another will result in a lot of debate. Where one zone’s upgrade will benefit the economy, another will benefit the impoverished. It seems very likely though, that because of the major economic improvement that comes with upgrading zone C, it may be chosen first. There are, however many negative externalities that can arise from giving either one preference, because upgrading one first will always leave the others still causing environmental and social damage.
The organizations involved in upgrading these zones are People’s Gas, the City and County governments, Alcosan, and Pittsburgh Water and Sewer Authority (PWSA). These institutions face multiple challenges - social, political, economic, environmental - over the course of their decision making process to prioritize the zone upgrades and think about whether upgrading certain zones would be worth it in the long run. Some of the key obstacles