https://www.khanacademy.org/science/ap-college-environmental-science/x0b0e430a38ebd23f:aquatic-and-terrestrial-pollution/x0b0e430a38ebd23f:waste-disposal-reduction-and-treatment/v/ap-es-sewage-treatment 2024-06-21T23:15:14.703721694Z Sewage treatment The process of waste disposal, reduction, and treatment involves primary, secondary, and sometimes tertiary treatments. Primary treatment physically removes large objects, while secondary treatment uses aerobic bacteria to break down organic waste. Tertiary treatment, though not always used due to cost, targets specific wastewater components for removal. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/09af1cda-eb97-461f-8326-3c1946c6a972_1280_720_base.png Sewage treatment The process of waste disposal, reduction, and treatment involves primary, secondary, and sometimes tertiary treatments. Primary treatment physically removes large objects, while secondary treatment uses aerobic bacteria to break down organic waste. Tertiary treatment, though not always used due to cost, targets specific wastewater components for removal. https://cdn.kastatic.org/ka-youtube-converted/_a8Mbkt_o80.mp4/_a8Mbkt_o80.mp4 293 Solving environmental issues https://www.khanacademy.org/science/ap-college-environmental-science/x0b0e430a38ebd23f:aquatic-and-terrestrial-pollution/x0b0e430a38ebd23f:waste-disposal-reduction-and-treatment/e/waste-disposal-reduction-and-treatment 2022-09-07T01:03:50.067296221Z Waste disposal, reduction, and treatment Apply your understanding of waste disposal, reduction, and treatment in this set of free practice questions aligned to AP standards. exercise https://www.khanacademy.org/science/middle-school-earth-and-space-science/x87d03b443efbea0a:earth-and-society/x87d03b443efbea0a:human-impacts-on-the-environment/v/human-impacts-on-the-environment 2025-05-07T17:11:10.976262835Z Human impacts on the environment Human activities—such as land use, water use, and deforestation—often have negative impacts on the environment. These impacts worsen as the human population grows and consumes more resources. Science can help identify ways to reduce our impacts, but it is ultimately up to us to take action. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/5d88359d-4b8d-407f-86f3-06c1792814a4_1280_720_base.png Human impacts on the environment Human activities—such as land use, water use, and deforestation—often have negative impacts on the environment. These impacts worsen as the human population grows and consumes more resources. Science can help identify ways to reduce our impacts, but it is ultimately up to us to take action. https://cdn.kastatic.org/ka-youtube-converted/ThpzFgoGrKE.mp4/ThpzFgoGrKE.mp4 308 Solving environmental issues https://www.khanacademy.org/science/middle-school-earth-and-space-science/x87d03b443efbea0a:earth-and-society/x87d03b443efbea0a:human-impacts-on-the-environment/e/apply-human-impacts-on-the-environment 2026-06-01T10:10:43.143771843Z Apply: Human impacts on the environment Apply your understanding of human impacts on the environment in this set of free practice questions aligned to NGSS standards. Lauren Rosebrugh exercise https://www.khanacademy.org/science/middle-school-earth-and-space-science/x87d03b443efbea0a:earth-and-society/x87d03b443efbea0a:human-impacts-on-the-environment/a/human-impacts-on-the-environment 2026-04-29T10:50:35.589391704Z Key points: Human impacts on the environment Learn about how human activities can affect the environment. article https://www.khanacademy.org/science/teacher-resources-ngss-science-domain/x2811526c37de0eab:hands-on-science-activities/x2811526c37de0eab:middle-school-earth-and-space-science-activities/a/activity-how-can-we-reduce-our-garbage-footprint 2026-02-27T18:00:31.886851552Z Activity: How can we reduce our garbage footprint? Make science come alive in your classroom with this free hands-on activity aligned to middle school NGSS standards. article