10: Air 12: Emissions 13: Haze 14: Indoor Air 30: Health 31: Children's Health 63: Pollutants 90: General	20: Earth 21: Global Warming 22: Ozone	30: Health 31: Children's Health 32: Risk Assessment
40: Land 41: Conservation 42: Farming 43: Organic 44: Land Use 45: Biosolids	50: Legislation/Legal 53: Pennsylvania 54: Environmental Justice	60: Science 61: Animal 62: Biology 63: Pollutants 64: Earth Sciences 65: Economics
70: Waste 71: Landfills 72: Recycling 73: Sewage 74: Combustion 90: General	80: Water 33: Disease 87: Watersheds	90: General