Environmental Impact of Green Burial

Unlike traditional burial methods that emphasize the use of embalming and non-biodegradable caskets, green burials minimize the risk of contaminated groundwater and soil by avoiding harmful chemicals, using biodegradable materials, and encouraging natural decomposition. Embalming fluids, varnishes, and metal components of caskets all have the potential to leach into groundwater and soil over time. Cement used in burial vaults, while not toxic in itself, relies on resource-intensive mining and manufacturing processes that contribute to carbon emissions. In an effort to preserve nature and protect its habitats and wildlife, these elements are generally eliminated in the preparatory and funerary processes at natural burial grounds. 

Soil also acts as a filter for buried bodies or items that are buried with the body. The degree of filtration can vary based on the characteristics of the soil and whether clay or other organic matter is present. For green burial, important variables to achieve ideal soil conditions include salt levels, alkalinity, soil texture, the presence and depth of bedrock, and other elements. The body itself is fully biodegradable and will eventually degrade into the soil, which will typically become sterile over time. Aside from the chemicals and medications already released during decomposition, without embalming fluids present, the body is unlikely to leach other harmful compounds or chemicals into the ground.

Most green burial grounds, including hybrid, natural, and conservation cemeteries, follow strict guidelines to maintain environmentally sound practices that protect the surrounding ecosystem. These are often based on certification standards set by organizations like the Green Burial Council, and they also comply with applicable state and local public‑health or environmental rules. For example, many limit what materials can be brought onto the grounds or how bodies can be buried. Some also have specific requirements regarding only using non‑toxic landscaping products and emphasize efforts to protect water sources such as lakes and rivers. In particular, conservation burial grounds, which are often joint ventures with land‑trust organizations, have the added aim of permanently protecting the land from development, thereby helping to safeguard the environment from contamination. By adhering to these guidelines and practices, green burial grounds are able to minimize the risk of contamination from burial sites and general upkeep of the grounds.

Sources

“Rest in Peace, Not Pollutants: Green Burials Say ‘No Thanks’ to Chemicals in the Grave”. ecoRI News. https://ecori.org/rest-in-peace-not-pollutants-green-burials-say-no-thanks-to-chemicals-in-the-grave/

“Going out Green: Four Ways to Ensure an Eco-Friendly Burial”. Green Burial Council. https://www.greenburialcouncil.org/ensure_eco-friendly_burial.html

“Green (Natural) Burial Frequently Asked Questions”. Peaceful Passage at Home. https://peacefulpassageathome.com/green-natural-burial.html 

“Grave Science Soil and Water”. Green Burial Council. https://www.greenburialcouncil.org/grave_science_soil_water.html 

“6 Myths About Green Burial”. Morgan Oaks Eternal Preserve. https://www.morganoaksgreenburial.com/2022/09/01/6-myths-about-green-burial/ 

The science of decomposition is complex, and scientists don’t have a full understanding of all of the chemical reactions that happen after death. However, after years of study in outdoor laboratories known as “body farms,” they have been able to see some of what happens to the human body and the surrounding area as it decays. Importantly, the depth of burial significantly affects this process. In the shallow, oxygen-rich soil typical of natural or conservation burials (often around 3-4 feet), aerobic bacteria drive a composting-like breakdown. In deeper, anaerobic environments (such as traditional 6-foot burials), decomposition follows a different path dominated by putrefaction.

According to scientific research covered by The Guardian, a decomposing body changes the chemistry of the soil in which it is buried, sometimes for many years. As tissues break down due to insect and microbial activity, fluids leach from the body. These, in turn, release nutrients into the surrounding soil, which are carried through insect activity to a concentrated area — a “cadaver decomposition island” of organically rich soil. Processes like those offered by NOR, which use carefully controlled aerobic decomposition to transform the body into soil, aim to optimize this natural nutrient cycle. According to one study, each kilogram (2.2 pounds) of dry body mass releases 32 grams of nitrogen, 10 grams of phosphorus, 4 grams of potassium, and 1 gram of magnesium into the soil. These nutrients benefit the ecosystem by generating greater biomass, more nematode activity, and more diverse plant life.

At the same time, a decomposing human body releases a number of toxic chemicals, such as freon, benzene and carbon tetrachloride, into the surrounding environment as well. Additionally, medications the person was taking prior to death are often present in decomposing organs and tissues, and may be released into the surrounding soil. It’s important to note, however, that not all drugs remain in body tissues after death. According to Australasian Science, bacteria such as Escherichia coli, which are present in the intestine during life, invade the body after death and metabolize or neutralize certain drugs. Further, most of the toxins and residual medications that remain in the body soon dissipate in the soil through natural attenuation, a four-fold process that includes microbial activity (including the activity of certain fungi) dilution by groundwater, absorption, and evaporation into the air. This natural filtration is a key reason for regulations governing cemetery placement, particularly their minimum required distance from groundwater sources, to prevent contamination.

Sources

“Life after death: the science of human decomposition”. The Guardian. https://www.theguardian.com/science/neurophilosophy/2015/may/05/life-after-death 

“Natural Attenuation”. Clean Up Information – United States Environmental Protection Agency. https://clu-in.org/techfocus/default.focus/sec/Natural_Attenuation/cat/Overview/ 

“Common Types Of Fungi Found In Soil”. Sciencing. https://www.sciencing.com/common-types-fungi-found-soil-6365925/