OVERALL, THE Boston may­oral can­di­dates agree with the city’s goal to cut green­house gas emis­sions. Sev­eral have men­tioned that they want to see improve­ment in Boston’s recy­cling rate, which, at 20 per­cent, is 10 per­cent lower than the national average. But to match recy­cling rates of 80 per­cent in San Fran­cisco, 65 per­cent in Los Angeles, or 55.7 per­cent in Seattle (a city com­pa­rable to our own size), we need to go a lot fur­ther than the sug­ges­tion of John Con­nolly and Felix Arroyo to add more recy­cling bins on streets and in parks or Char­lotte Golar Richie’s idea of recy­cling competitions.

San Francisco’s high rate of diver­sion of waste from land­fills is partly because the city has been col­lecting organic waste at curb­side along with reg­ular recy­cling since 1996. Organic waste, which includes food scraps, yard clip­pings, pizza boxes, paper, and paper­board, com­prises 56 per­cent of the waste stream nation­ally. Once buried in a land­fill, it pro­duces methane — a green­house gas that is 20 times more potent than carbon dioxide, even though it stays in the atmos­phere a shorter time. Food waste in Boston com­prises 20 to 25 per­cent of the cur­rent waste stream (not including paper and paper­board), so recy­cling it would put us in line with other leading cities.

Organic waste is recy­cled through indus­trial scale com­posting or anaer­obic diges­tion, the latter of which is sup­ported by all the can­di­dates who answered envi­ron­mental ques­tions posed by the Globe. Anaer­obic diges­tion cap­tures reusable biogas by breaking down bac­teria in an oxygen-​​free envi­ron­ment. The resulting product, which is 60 to 70 per­cent methane and 30 to 40 per­cent carbon dioxide plus trace ele­ments, can be used for fuel in many types of appli­ca­tions. Manure from agri­cul­tural sources is often used in digester projects, and organic waste from house­holds and com­mer­cial enter­prises could meet more of our region’s power needs through diverted waste materials.

Read the article at The Boston Globe →