Script image posted August 03, 2014; text on page last updated September 03, 2015

With agriculture our first focus is to ensure safety of the soil before anything is cultivated for consumer use.  Plants take in a cross spectrum of contaminants from the land, which gets transferred up the food chain.  If unsure about the status of a location, phytoremediation could be used, where certain plants are designated to absorb elements then have tissues tested for composition.  When harmful substances are identified, disposal and element reclamation should be handled under hazmat guidelines and the original location avoided without proper equipment, until proven otherwise. Those involved in the operation maintain records of the area each sample is from, so they can trace back to specific sections.  The process is repeated on a continual basis until subsequent generations test clear.

Guidelines are not complete, in terms of the correct spacing between plots for different foliage, given variations in root structures; in other words the ranges of clearance are to be determined.  Also one must assume the soil will be safe only to the depth of the respective roots, so it is becoming standard practice for gardeners to instead add on top of unfit soil with enough clean quantities to match the maximum depth of an intended crop, so it will not reach the unsafe portion.  Another option is to remove tainted layers then run the treatment process on them in a separate, isolated facility.

Similar methods apply for water sources, utilizing varieties of algae and seaweeds.  Yields from lakes and streams may be deemed inedible on account of runoff from surrounding areas, with portions of oceans also now a concern.  Conditions can be controlled more carefully by maintaining a self-contained water supply for raising fish, as in aquaponics, where the fish generate ingredients for fertilizers as a byproduct, whereas treating large bodies of water is less practical in the short term.

Characteristics of plant types best suited for remediation include speed of turnover, along with versatility in the range of compounds capable to siphon out for removal and testing.  It is also an advantage when portions of the product itself, once confirmed clear, can be used for food preparation or industrial purposes.  Notably hemp is demonstrated to offer such benefits, including applications with housing and transportation.  On the other hand it needs to be noted under most classifications hemp is considered a weed, which if left unchecked provides a habitat for vermin and venomous creatures.  Neighborhoods maintain ordinances to prevent such hazards from affecting occupants.  In general areas where remediation takes place are to be kept off limits, except for licensed workers with protective attire.  Pesticides cannot control all concerns and if anything add to the contamination.  Machinery should be integrated as much as possible and workers’ body parts kept away from the area, unless behind protective barriers and inspected before leaving the site.  Segments of residential areas may be “sectioned off,” made inaccessible while the process is underway.  As for legal restrictions concerning controlled substances derived from a variation of the hemp plant, to produce in this fashion requires pest control throughout the growth cycle, so it is unfair to make this association.  On a side note types of trees and bamboo offer their own advantages, and certain fungi have also demonstrated attributes for cleansing soil, in which case the process is referred to as mycoremediation.

On the other side of the coin – the act of remediation to remove harmful elements will strip needed nutrients and minerals as well.  Growing crops in general can lead to soil loss, which over time will render the land no longer viable at all.  For this reason planning needs to take into account adding organic matter, including compost, along with crop rotation between cycles, for instance involving cover crops / plants which have characteristics of nitrogen fixation.  Seaweeds can be used as fertilizers, yet going forward this likely will call for large scale aquarium / on-site production, so integrity from pollution can be assured.  Rocks & gravel dust, added to increase mineral content, should be tested as well if possible.

References (Last Updated May 10, 2021):

– Environmental Health – USGS
– Contaminants Found in Groundwater – USGS
– Phytoremediation of Heavy Metal Polluted Soils and Water – NCBI
– Phytoremediation: Using Plants To Clean Up Soils – USDA
– Phytoremediation Resource Guide – EPA
– Soil Contaminants – Cornell
– Urban Gardening: Managing the Risks of Contaminated Soil – EHP
– Benefits of Rotational Grazing – UVMg
– Seaweed: The New Trend in Water Purification – UConn Today
– Could Bamboo Help in Remediation of Waste Sites? – Science Daily
– Hemp Industries Association – Facts
– Industrial Hemp in the United States – Harvesting, Retting, and Fiber Separation – USDA
– National Agroforestry Center – USDA
– Welcome to the PLANTS Database – USDA Plants
– International Organization for Standardization – Harvesting Equipment
– Agriculture Crop Production Harvest – EPA
– National Ag Safety Database
– Residential Proximity to Agricultural Pesticides – EHP
– A Growing Problem – Nature Research
– Organic Arsenicals – EPA
– Detection of Glyphosate in Malformed Piglets – Omics Group
– Health Effects of Biosolids Applied to Land – VDH
– Risk of Intestinal Parasitic Infections in People with Different Exposures to Wastewater and Fecal Sludge in Kampala, Uganda: A Cross-Sectional Study – PLOS
– Kim Jong Un May Have Caused a Parasitic Worm Epidemic in North Korea By Making Farmers Spread Human Feces on Their Crops – Newsweek
– Sewage Sludge Victims
– Understanding PCB Risks – EPA
– Water Quality Information Center – Conservation Effects Assessment Project
– Toxic Chemicals Sneak Out of Homes via Dirty Laundry – NRDC
– Division of Ecological Restoration – Mass
– Superfund – Cleaning up the Nation’s Hazardous Wastes Sites – EPA
– Soil Pollution in China Still a State Secret – Scientific American
– The Soil Pollution Crisis in China Presents Daunting Challenge – Yale
– Yards Pose Health Risk to Kids, Moms Near Factory Site – USA Today
– Injection Wells: The Poison Beneath Us – ProPublica
– Food Affected by Fukushima Disaster Harms Animals, Even at Low-Levels of Radiation – AAAS
– Radiation Detected In Drinking Water In 13 More US Cities, Cesium-137 In Vermont Milk – Forbes
– Radioactive Leaks Found at 75% of US Nuke Sites – CBS News
– Radioactive Wild Boar Roaming the Forests of Germany – Telegraph
– At Chernobyl, Radioactive Danger Lurks in the Trees – Scientific American
– Test Reveals Radioactive Chernobyl Residue in Milk From Belarus – US News
– Source of Lead-210 and Polonium-210 in Tobacco – Science Mag
– Tobacco Smoke – Radiation Protection – EPA
– The Tobacco Industry’s Response to the Polonium-210 Issue – NIH
– Into the Weeds: Regulating Pesticides in Cannabis – NIH
– New Species of Metal-Eating Plant Discovered in the Philippines – Science Daily
– Banana Peels May Help Filter Pollutants Out of Water – Live Science
– Mushroom as a Product and Their Role in Mycoremediation – NIH
– Heavy Metals Accumulate More In Some Mushrooms Than In Others – Science Daily
– Only 60 Years of Farming Left If Soil Degradation Continues – Scientific American
– Soil Erosion – Causes and Effects – OMAFRA
– A Study on the Mineral Depletion of the Foods Available To Us as a Nation Over the Period 1940 to 1991 – NIH
– How to Convert an Inorganic Fertilizer Recommendation to an Organic One – UGA
– About Cover Crops – USDA
– Biological Nitrogen Fixation – Nature Education