news&views Autumn 2016 | Page 21

FROM THE BRANCHES transfer to the landfill . Later , we observed that separation process through windows in an overhead viewing gallery .

FROM THE BRANCHES transfer to the landfill . Later , we observed that separation process through windows in an overhead viewing gallery .

Organic waste is transferred to the Edmonton Composting Facility which opened in 2000 and occupies a space equivalent in size to five football fields .
To the left we could see five biosolids lagoons , storage cells where sewage biosolids from the Gold Bar Wastewater Treatment Plant are stored before being added to the mixture . The blended material reaches a temperature of 55 ° C and is stirred to add oxygen . After wood chips are incorporated , the composting biosolids are moved to an outdoor area for about six months of curing . Each year quality compost is created from 160,000 tonnes of organic waste and biosolids and marketed for use in local agriculture and horticulture .
Directly below us was the Global Electric Electronic Processing ( GEEP ) building , the electronics graveyard where electronics from Edmonton ' s Eco Stations are processed ( 80 % of the discarded computers and televisions still work ).
The Construction and Demolition Waste Cycling Facility , located in the centre of the complex , transforms wood , drywall , concrete , asphalt , metals and asphalt shingles .
In the distance was the Enerkem Biofuels Facility , the newest structure , where non-recyclables and non-compostable waste is shredded to produce garbage ' fluff .' This dry , carbon-rich feedstock is heated to produce ' syngas ,' which is converted into methanol and ethanol . Telephone poles and railway ties are stockpiled for future use in biofuel production . Currently , the biofuel plant operates part-time and addresses only household refuse , but the intent is to process commercial waste in the future , too .
From a viewing gallery , we saw how 70,000 tonnes of recyclables are sorted and prepared for market each year in the Materials Recovery Facility — one of the most advanced plants of its kind in North America . Paper , plastic , metal and cardboard are baled into large cubes and sold on the global market . The facility realizes about $ 10,000 a month from recyclable items that have been returned to bottle depots for refund .
We learned that the closed Clover Bar Landfill has a number of sophisticated characteristics . It was the first engineered sanitary landfill to feature groundwater diversion , leachate treatment and environmental monitoring . A clay liner on the bottom of the hole keeps waste contained , pipes along the hillside are checked on a continuous basis , leachate is pumped out daily for processing , and methane gas is collected and supplies electricity to the grid to power 4,600 homes in Edmonton .
Our guides , Neil and Helene , stated that the landfill is to be capped with three feet of clean soil , trees will be planted and the site will become a park .
ERTA members who participated in the Waste Management Centre tour left with a new appreciation for the City of Edmonton ’ s unique approach to dealing with waste generated within its boundaries . This is a wonderful field trip for anyone interested in what human ingenuity has and can accomplish — when the will exists .
news & views AUTUMN 2016 | 21