A.KE Team Kenya

Over the years, groundwater have become contaminated by a growing number of organic and inorganic substances ranging from Per- and polyfluoroalkyl substances (PFAs), Pesticides, Emerging contaminants petroleum-derived hydrocarbons to radioactive compounds, to cancer-causing hexavalent chromium. The importance of uncontaminated groundwater for agriculture, human consumption, and the environmental health of ecosystems is paramount to the health and productivity of industrial society. Water scientists and managers are focused on developing cost-effective methods to reverse this trend. Several methodologies have been developed, however few are as cost-effective as the use of readily available materials, such as Activated Carbon and Bio pesticides, to handle plumes caused by the slow discharge of contaminants from low permeable zones and eliminating contaminants originating from the use of pesticides within the matrix of a permeable barrier. Groundwater Remediation using Permeable Reactive Barriers presents readers with this latest technology and developments within four main sections:

1. Innovations in Design, Construction, and Evaluation of PRBs
2. Development of Reactive Materials
3. Evaluations of Chemical and Biological Processes
4. Case Studies of Permeable Reactive Barrier Installations

What is going on in Region Zealand?

Is the largest and most populous Island of Denmark, lying between the Kattegat and the Baltic Sea, separated from Sweden by the sound and from Funen by the Great Belt. By January 2020, it had a population of 2, 319,705 (Statistics Denmark). It is the 13^th largest Island in Europe by the area, and the 4^th most populous.

Coordinates: 55 30′ N 11 45′

Elevation : 122.9m (403.2Ft)

Main Activities:

Agriculture and Manufacturing

Water situation in Region Zealand

Groundwater is one of the important sources of water for agriculture, industry and domestic use in Region Zealand. Owing to Region Zealand’s terrain of high elevation and steep slopes, most precipitation becomes near surface runoff to the east and west coasts of the Island.

The Challenge:

Clean groundwater, being a resource for e.g. drinking water and food production, is essential to life on Earth. Nevertheless, this resource is more than ever under pressure due to contamination arising from human activities and increasing consumption. The artificial chemicals have throughout the years been introduced to the environment due to spills, leaks and former practice for handling of chemical waste. Several of these chemicals are health and environmental hazards. Thus, the need for protection of the groundwater resource through efficient remediation of soil and groundwater is unquestionable and it has to be acted by now. The longer we wait, the more troublesome and expensive the task. Only then can we ensure a safe drinking water resource for us and the generations to come, which is one of Region Zealand’s tasks ( from the challenge description of Region Zealand)

The current remediation technologies and strategies are challenged by

1. several of the contaminants being persistent, and
2. complex contaminant mixtures of diverse physico-chemical properties.

Thus, for the different contaminant groups, varying efficiencies by current remediation technologies are reached. In addition, at most, we only find the compounds that we are looking for. In practice, since remediation efforts are tailor-made for a site based on e.g. the contaminant composition, remediation plants fail, must be rebuilt when awareness on previously overlooked contaminants rise or a previously remediated site must be revisited. At present, the problem at hand in Region Zealand:

• Persistent pesticides
• Perfloroalkyl substances (PFAS) and
• Emerging contaminants or contaminantsof emerging concern, challenges the remediation technologies and therefore have a higher risk of reaching drinking water catchment areas.
• Our Solution

In situ bioremediation by use of Bacteria Gordonia, Permeable Reactive Barrier with Granular Colloidal Activated Carbon and Replacement of Pesticides with Biopesticides.

INTRODUCTION

AC technology has mostly been used to handle persistent plumes caused by the slow discharge of contaminants from low permeability zones. In situ adsorption and degradation are thought to be more cost-effective than pump and treat (P&T) systems and to maintain treatment effectiveness for longer than degradation alone. The long-term effectiveness of AC-based technology has been proved in several field applications.

Current troublesome contaminants in Region Zealand

1. Per- and polyfluoroalkyl substances (PFAs) and
2. Pesticides
3. Emerging contaminants

The Permeable Reactive Barrier with Granular Activated Carbon as a reactive media illustrated in the figure below.

What Are PFAs (Perfluorinated Aromatic Substances)?

Nonstick coatings, textiles, paper goods, some firefighting foams, and a variety of other products all contain PFAs. Because they repel oil and water, tolerate temperature extremes, and minimize friction, these compounds have a wide range of manufacturing and product uses. PFAs are organic molecules with a wide range of molecular weights, structures, and functional groups. These compounds have accumulated in the environment as a result of their manufacture and use over time.

Activated carbon efficiency on ECs and PFAs removal is dependent of several factors:

1) Carbon material/porosity,

2) Feed water quality,

3) PFAs target characteristics, and

4) PFAs-activated carbon contact duration during the adsorption process

The reason of specifically choosing liquid activated carbon is because it is able to distribute better into the soil layers as compared to solid counterparts.

Implementation

Illustration of the plume infiltrating into the ground as shown below and intervention techniques through injection wells and the process control.

A liquid AC (LAC) will be injected under pressure and are not expected to travel long distances. The total mass of a pollutant in both high and low permeability zones is often used to estimate the design loading rate of LAC. The dissolved contaminant mass flow is used to calculate the design loading rate of colloidal AC-based products.

Multiple lines of evidence are required for performance monitoring of in situ AC-based remedial technology to confirm that contaminants are eliminated not just by adsorption but also by degradation.

To eliminate the need of removal of the installed activated carbon barriers upon saturation – our solution is focusing on bio-degradation of trapped contaminants by using microbes to break them down.

We are assuming ‘low levels of PFAS in large amounts of contaminated material’ kind of situation, and for sure biological treatment may be more cost effective. Our innovating idea is to blend in aerobic Gordonia bacteria onto contaminants source sites top soils for them to act on the PFAs prior to it getting to the installed liquid activated carbon barrier.

Main factors to consider during remedial design

1. Defining optimal injection locations and loadings
2. Subsurface geology and contaminant mass distribution
3. injection loading and approach were adjusted to the contaminant distribution pattern, which significantly improved the remedy performance
4. The calculation of contaminant loading needs to consider the rates of back diffusion of source material or the total mass of contamination.

Reasons for choosing PRBs to other methods:

Some of the methods have been applied and it has been realised that no one method fits all as some methods have managed to clear the contaminants but some contaminants have been transformed into other phases thus prompting for the secondary solutions which happens to be costly. Thus PRBs will be able to deal with sturbon contaminants once and for all like PFAs, and emerging contaminants such as TCE, PCP, PCEs, BTEX from pharmaceuticals.

The sustainable use of Biopesticides in place of chemical pesticides

Biopesticides are effective in little amounts and degrade quickly, resulting in smaller exposures and avoiding the pollution problems that conventional pesticides produce.

In general, biopesticides are less hazardous than conventional pesticides and instead of having a broad-spectrum like conventional pesticides, which could also harm other untargeted creatures like birds, insects, and mammals, biopesticides often affect only the target pest and closely related organisms.

Further research is required in the creation of biopesticides that will be effective to the pest problems currently faced in the Zealand region because when it comes to protecting the groundwater resource this will be a long-term prevention measure from contamination – a proactive solution.  

Examples of Biopesticides:

• Daisy plants (Chrysanthemum cinerariaefolium) were first used centuries ago as a lice remedy in the Middle East, and this led to the discovery of pyrethrum insecticides. …
• In South America, the natives use an extract of a forest vine to stun fish; this led to the discovery of rotenone, a biodegradable insecticide.
• The bacterium Bacillus thuringiensis produces toxic proteins that kill certain insects but are apparently harmless to humans. These are being produced and marketed as biopesticides.
• The Neem tree, in India, has been found to be a source of the insecticide azadirachtin, as well as fungicides, spermicide.

What are Microbes?

A microbe, or “microscopic organism,” is a living thing that is too small to be seen with the naked eye. We need to use a microscope to see them. The term is very general. It is used to describe many different types of life forms, with dramatically different sizes and characteristics:

• Bacteria
• Archaea
• Fungi
• Protists
• Viruses
• Microscopic Animals

The human body is home to microbes from all of these categories. Microscopic plants are also considered microbes, though they don’t generally live on or in the human body.

Looking into the bacteria as a Microbe and more so down the line into specific one as Gordonia.

Why bacteria gordonia as the choice for this project?

Bacteria are everywhere on earth including environments with extreme heat, cold, pH, radiation UV and also they are;  adaptive, resilient and can thrive in an environment impaired by contaminants.

Description and Significance of Gordonia

The genus of Gordonia was originally proposed as Gordonia 1971 by Tsukamora M for a bacterium isolated from the spit of patients with pulmonary disease and soil. It was named Gordonia to pay tribute to an American Bacteriologist Ruth E. Gordon. This genus was eventually discarded then reinstated later and in 1997 it was renamed Gordonia.One of the most significant things about these bacteria is that they have the ability to degrade some xenobiotics, pollutants, and some other slow to biodegrade products. They also have applications in biotechnology with their ability to synthesize potentially useful compounds. The fact that many species of Gordonia are opportunistic pathogens, limits this application though. (Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

Cell Structure and Metabolism

Gordonia members are characterized as aerobic, nonmotile bacteria that can be gram-positive to gram-variable actinomycetes. They are also catalase-positive, slightly acid-fast, with some apparent susceptibility to lysozyme. Because the Gordoniae resemble the Nocardiae, the Gordoniae are referred to as nocardioforms. This means that their mycelial growth fragments into bacillar to coccoid filaments. No spores are produced ((Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

Metabolically, Gordoniae are oxidative with a preference for breaking down carbohydrates for energy. Although a wide variety of other substances can be broken down as well, Gordoniae are arylsulfatase negative. [(Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

Colony morphology has great variety even within the same species (such as Gordonia alkanivorans DSM 44369 and Gordonia westfalica DSM 44215) or the medium used. Colonies range from slimy, smooth, glossy, irregular, and rough with colors spanning white, tannish, yellow, orange, red, and pink. The morphology of colonies appears able to be manipulated. MK-9(H2) is the dominant menaquinone/isoprenologue. MK-8(H2) is only found in traces of some species. These cell wall and cellular chemotaxonomic properties separate Gordonia from related genera such as Mycrobacterium, Rhodococcus, and Skermania (Baumeister, D., Berekaa, MM., Pötter, G., Kroppenstedt, R.M., Linos, A., Steinbüchel, A., 2001).

Ecology

The Gordonia genus includes a variety of versatile species that have been isolated from multiple types of environments. [Baumeister, D., Berekaa, MM., Pötter, G., Kroppenstedt, R.M., Linos, A., Steinbüchel, A., 2001] Gordonia have been found terrestrially in soil and mangrove rhizospheres. [Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

They have also been found in aquatic environments including both marine and freshwater ecosystems. [Baumeister, D., Berekaa, MM., Pötter, G., Kroppenstedt, R.M., Linos, A., Steinbüchel, A., 2001] Gordonia have been specifically isolated from estuary sands as well, (Bröker, D., Arenskötter, M., Legatzki, A., Nies, D. H., & Steinbüchel, A. (2004). Because Gordonia are highly capable of breaking down waste products, they have been largely grown in oil-producing wells, hydrocarbon-contaminated soil, wastewater treatment plants, bioreactors and biofilters, and activated sludge. [Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

[Bröker, D., Arenskötter, M., Legatzki, A., Nies, D. H., & Steinbüchel, A. (2004)]. Gordonia are also found to have symbiotic relations with multiple hosts in marine and freshwater environments as well as terrestrial invertebrates. [Baumeister, D., Berekaa, MM., Pötter, G., Kroppenstedt, R.M., Linos, A., Steinbüchel, A., 2001] A few species such as G. aichiensis, G. araii, G. bronchialis, G. effusa, and G. sputi were actually originally isolated from clinical specimens, so it is not uncommon for Gordonia species to be found inhabiting humans, too. [Bröker, D., Arenskötter, M., Legatzki, A., Nies, D. H., & Steinbüchel, A. (2004), and Drzyzga, O. (2012).]

Application to Bioremediation and Biotechnology

The members of the genus Gordonia are very diverse in their abilities to degrade various hydrocarbons, pollutants, xenobiotics, and natural compounds that are not readily biodegradable. This makes the Gordoniae very good candidates for bioremediation, however past infections in high-risk individuals may limit their use. Some molecules and compounds that can be broken down are phthalic acid esters, s-triazine and alkylpyridines, DBT and biodesulfurization, other xenobiotics, and natural and synthetic rubbers. Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004).

Finally the substrate for the bacteria are naturally occurring through reduction and oxidation processes that takes place. Whereby, the six elements that is Carbon(C), Hydrogen (H₂), Nitrogen (N₂), Oxygen (O₂), Sulfur (S) and Phosphorus (Po). Carbon responsible for building biomass for bacteria, Hydrogen as an electron donor and Oxygen as electron acceptor which energizes the bacteria during the culture and the other elements which will act as electron donors or acceptors but largely are required by the microbe in small quantities. The bacteria Gordonia thrives in aerobic conditions, requires pH and responds well in radiation (UV).

The temperature condition for the microbe is 28⁰ C, the case with Region Zealand is.

The contaminants to be handled by In – Situ Bioremediation (ISB):

1. Trichloroethane (TCA)
2. Trichloroethene (TCE)
3. Benzene, Toluene, Ethyl Benzene, and Xylene
4. Polychrolinated biphenyls (PCB)
5. Perchloroethene (PCE)
6. Pentachlorophenol (PCP) .

References

Arenskötter, M., Baumeister, D., Berekaa, MM., Pötter, G., Kroppenstedt, R.M., Linos, A.,   

         Steinbüchel, A. Taxonomic characterization of two rubber degrading bacteria belonging

         to the species Gordonia polyisoprenivorans and analysis of hyper variable regions of

        16S rDNA sequences, FEMS Microbiology Letters, Volume 205, Issue 2, December

        2001, Pages 277–282, https://doi.org/10.1111/j.1574-6968.2001.tb10961.x.

Arenskötter, M., Bröker, D., & Steinbüchel, A. (2004). Biology of the metabolically diverse

        genus Gordonia. Applied and environmental microbiology, 70(6), 3195

        –3204. https://doi.org/10.1128/AEM.70.6.3195-3204.2004.

Bröker, D., Arenskötter, M., Legatzki, A., Nies, D. H., & Steinbüchel, A. (2004).

         Characterization of the 101-kilobase-pair megaplasmid pKB1, isolated from the rubber

         -degrading bacterium Gordonia westfalica Kb1. Journal of bacteriology, 186(1), 212

         –225. https://doi.org/10.1128/JB.186.1.212-225.2004.

Drzyzga, O. (2012). The strengths and weaknesses of Gordonia: A review of an emerging

         genus with increasing biotechnological potential. Critical Reviews in Microbiology,

         38:4, 300-316, DOI: 10.3109/10

Business Canvas Model

Robert Juma Wamalwa

JKUAT

MSc. Environmental Engineering and Management Ongoing

Competences: Creative thinker, Project management skills, Team player, problem solving skills, analytical skills and Industry skills

am good at discovering  new ways to save human lives by designing the water and wastewater management systems. Experienced in Environmental Audit.

JKUAT

MSc. Environmental Engineering and Management Ongoing

Competencies:

Teamwork and result oriented, Responsive decision making, resilient and good communication skills.

-Good at Strong work Ethic and Professionalism.

-Experienced in Analytical skills in Air, Water and soil.

References

Gomes, I.B., Maillard, JY., Simões, L.C. et al. Emerging contaminants affect the

         Microbiome of water systems—strategies for their mitigation. npj Clean

         Water 3, 39 (2020). https://doi.org/10.1038/s41545-020-00086-y

Yinsong Liu, Jingchun Wu, Yikun Liu, and Xiaolin Wu, Biological Process of

         Alkane Degradation by Gordonia, ACS Omega 2022 7 (1), 55-63. DOI:

        10.1021/acsomega.

Removal of perfluoroalkyl acids from the drinking water production chain, KWR

         PFAS: Drinking Water Treatment, EPA, Calgon Carbon, Pittsburgh PA, 1

         March, 2018

Adeniji, Adebowale. 2004. Bioremediation of Arsenic, Chromium, Lead, and Mercury. National Network

of Environmental Management Studies Fellow Paper Prepared for the U.S. Environmental

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Environment (AFCEE). 2004. Principles and Practices of Enhanced Anaerobic Bioremediation of

Chlorinated Solvents. August. On-line address:

www.costperformance.org/remediation/pdf/principles_and_practices_bioremediation.pdf.

AFCEE. 2007. Final Technical Protocol for In Situ Bioremediation of Chlorinated Solvents Using Edible Oil.
Technical Directorate. Environmental Science Division. October. On-line address:
www.clu-in.org/download/remed/Final-Edible-Oil-Protocol-October-2007.pdf
AFCEE. 2008. Final Technical Protocol for Enhanced Anaerobic Bioremediation Using Permeable Mulch
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address: www.clu-in.org/download/techdrct/Final-Biowall-Protocol-05-08.pdf.
Alexander M. 1994. Biodegradation and Bioremediation. Academic Press, New York, NY. 286 p.
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Appl Environ Microbiol. Vol. 57 No. 4. Pages 1031-37.
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Metzler, A. Peacock, D.C. White, M. Lowe, D.R. Lovley. 2003. “Stimulating the in situ activity of
Geobacter species to remove uranium from the groundwater of a uranium-contaminated
aquifer.” Appl Environ Microbiol. Vol. No. 69. Pages 5884-91.
Balk, Melike, T. van Gelder, Sander A. Weelink, Alfons J.M. Stams. 2008. “(Per)chlorate Reduction by the
Thermophilic Bacterium Moorella perchloratireducens sp. nov., Isolated from Underground Gas
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Robert Juma Wamalwa

JKUAT

MSc. Environmental Engineering and Management Ongoing

Competences: Creative thinker, Project management skills, Team player, problem solving skills, analytical skills and Industry skills

am good at discovering    new ways to save human lives by designing the water and wastewater management systems. Experienced in Environmental Audit

Judy Mali Musilu

JKUAT

MSc. Environmental Engineering and Management Ongoing

Competencies:

Teamwork and result oriented, Responsive decision making, resilient and good communication skills.

-Good at Strong work Ethic and Professionalism.

-Experienced in Analytical skills in Air, Water and soil.