Operational Wastewater Production

Key takeaways

  1. Contaminants - from pesticides, household products, fashion, to waste - can cause water pollution when making their way into an aquifer.

  2. In your analysis, it is essential to assess what contaminants are released from the company and where, even though the contamination can spread far from the original polluting source.

  3. It is beneficial to add whether the concentration of chemicals/substances are exceeding safe levels.

  4. The breadth, depth, and persistence of the impact need to be evaluated in terms of the harm caused.

What it is?

Because water can dissolve substances, it is particularly vulnerable to pollution. Water pollution “occurs when harmful substances - often chemicals or microorganisms- contaminate a [body of water], degrading water quality and rendering it toxic to humans or the environment.”

Water pollution often occurs when toxic substances from farms, factories, and households make their way into an aquifer.

Categories of water pollution

  • Groundwater

  • Surface water

  • Ocean water

  • Point source

  • Nonpoint source

  • Transboundary


Common sources of water pollution

  • Agricultural

  • Sewage and wastewater

  • Oil pollution

  • Radioactive substances


Water pollution leads to the spreading of diseases, kills/harms biodiversity, and damages habitats.


Source

https://www.nrdc.org/stories/water-pollution-everything-you-need-know#whatis


SDG choice

✅ SDG 6

✅ SDG 14 (see aquatic ecosystem pollution)

Impact assessment

Water use, such as depletion, consumption, and withdrawal, is a separate topic to water pollution and discharge.

⚠️ Therefore, the topic of wastewater management is only relevant if the analysis is dealing with how the wastewater is polluting water supplies used for drinking/other uses.

The volume of water discharged alone is insufficient to assess the impact of wastewater. It is not relevant unless there is some negative impact.

In your analysis, you should analyze which contaminants were discharged (substance/type), where the pollution came from and where it went, as well as the quantity, and what the consequences or illnesses were contracted if ingested/used.


Remember to describe the scale of the impact by taking into account:


1/ The breadth of the impact

  • Is the impact local, national, or global?

  • How many water bodies/ areas are concerned?


2/ The depth of the impact

  • Is the water source profoundly affected, or does the issue just marginally impact them?

  • Are the changes brought by the issue profoundly changing society or the planet?


3/ The persistence of the impact

  • How long would the impact described last for? Months? Years? Decades?

  • How reversible is the impact described in the impact analysis? Can it be easily stopped/extended?



Help readers rate the company’s impact by linking studies to the chemical/element discharged by the company and making comparisons with competitors and industry average, when relevant.


To increase the robustness, it is valuable to know whether or not the wastewater was treated. If so, then how much of it was treated, and evaluate whether the number of pollutants in the wastewater discharged is above or below safe levels of the given areas. Even if the chemical concentration is below safe levels or below the maximum allowed emission of pollutants, the analysis should still be treated as a negative one.


If there is a clear impact on the local aquatic ecosystem, SDG 14 is more relevant. In that case, you should head to aquatic ecosystem pollution.

Additional Information on Assessing Pollution

The concentration of chemicals, which is commonly reported in wastewater samples as mg/L or ppm, shows the volume of a substance (i.e., mg of BOD) present in a known volume of wastewater (i.e., in 1 Liter).


Concentration is, therefore, a relative number and does not tell us how much there is of the chemical/substance, such as the mass or the weight that is being discharged.


The absolute number is referred to as loading. Loadings are commonly reported as kg per day (kg/d).

BOD stands for Biochemical Oxygen Demand and is defined as “the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample at a certain temperature over a specific time period.”


Other chemical measurements include:

  • COD (Chemical Oxygen Demand)
  • TOC (Total Organic Carbon)
  • O&G (Oil and Grease)



There are 4 main categories to measure wastewater quality:


1 - Organics


"A determination of the concentration of carbon-based (i.e., organic) compounds aimed at establishing the relative 'strength' of wastewater."

For example:

  • Biochemical Oxygen Demand (BOD)

  • Chemical Oxygen Demand (COD)

  • Total Organic Carbon (TOC)

  • Oil and Grease (O&G)



2 - Solids


"A measurement of the concentration of particulate solids that can dissolve or suspend in wastewater."


For example:

  • Total Solids (TS)

  • Total Suspended Solids (TSS)

  • Total Dissolved Solids (TDS)

  • Total Volatile Solids (TVS)

  • Total Fixed Solids (TFS)



3 - Nutrients


"A measurement of the concentration of targeted nutrients that can contribute to the acceleration of eutrophication."

For example:

  • Targeted nutrients: nitrogen and phosphorus

  • Acceleration of eutrophication: the natural aging of water bodies...etc.


4 - Physical Properties and Other Impact Parameters


"Analytical tests designed to measure a varied group of constituents directly impact wastewater treatability."

For example:

  • Temperature

  • Color

  • pH

  • Turbidity

  • Odor


Sources

http://butane.chem.uiuc.edu/pshapley/Environmental/L31/1.html#:~:text=BOD%20values%20are%20usually%20reported,20%20mg%2FL%20or%20less.

https://extension.uga.edu/publications/detail.html?number=C992&title=Understanding%20Laboratory%20Wastewater%20Tests:%20I.%20ORGANICS%20(BOD,%20COD,%20TOC,%20O&G)#:~:text=Concentration%20

Recommended articles