Noxious Odours Emitted from a Wastewater Treatment Plant - Essay Example

Running Head: ENVIRONMENTAL ISSUE: NOXIOUS ODOURS EMITTED FROM A WASTE WATER TREATMENT PLANT Student’s Name Subject Professor University/Institution Location Date Environmental Issue: Noxious odours emitted from a waste water treatment plant Introduction Communities in Australia produce large quantities of waste water with domestic water alone accounting for over seventy thousand litres per person every year. Industry and trade also emit waste water, and the treated waste water also known as effluent is usually released into the environment necessitating that it shoud be managed properly due to the public health hazards that it poses both to the public and the environment. A sewerage system collects the domestic and industrial waste water as well as waste water from manufacturing industries, treats it to the requisite levels and releases the resultant effluent that results from the process into the environment. In doing so, the sewerage system handles the liquid desecrate that is released by the communities for purposes of protecting the health of the health of the communities and the surroundings, takes care of the treatment and disposal, by disposing the effluent waste into a location that is situated far away from any personal property making it possible for higher concentration expansion to take place and also to allow for saving in the areas of energy, the supply of water and transportation. The sewerage system also assists in ensuring point source discharges of effluent which are easier to manage, monitor and modify as compared to diffuse discharges. The Australian effluent management framework is intended at ensuring that treated waste water is returned to the surroundings, in a way that is up to standard to the commnities in considerations of both environmental and cost factors. Some of the objectives of managing effluent are; to prevent the risk that it has on the health of the public, to make maximum use of the effluent (value of water and nutrients), reducing unfavourable effects that it may have on land as well as the pollution factors that it may harbor for both surface and underground waters “when used in land applications” and preservation of established water value purposes related to receiving waters when releasing is done to the surface waters. Water quality values in Australia are usually based upon considerations of the active ecology, the ecological values that are attributed to the use of the recipient water, the ecological current , among other community based goals. This paper aims at describing methods which could be used to measure the disbenefits that are caused by the release of effluent into the environment with specific reference to odour that emanates from this effluent substances. It will seek to explain how these methods operate as well as their values. The paper will also seek to establish the problems that are connected with thse ways and the advantages that they may hold over other methods. Discussion The Department of Environmental Protection (DEP) has the responsibility of dealing with complaits related to odour that affect the amenities of the commuities in Australia. The environmental Protection Act of 1996 particularly takes care of “Unreasonable emissions” which include emissions of noise, odour, and electromagnetic radition which irrationally impede on the health, wellbeing, calm, expediency or properties of people within a community. The standards of identifying what is unreasonable are supposed to be determined for each case since they differ from one case to the other (EPA NSW, 2001). Odour is particularly an issue in places where there are differences of land use which often results in receptives being situated near the source of the odour. The EPA guideline no. 47 on the assessment of odour impacts, calls for innovative suggestions and extension of available amenities. Odour guidelines related to existing facilities will however always be different for different situations (EPA Western Australia, 2002). The measurement of odours could be used to evaluate a variety of circumstances including; creating new facilities to manage odours or expanding on existing ones, coming up with ways of using land sensitively in an existing facility, looking into complaints of odour brought to DEP regarding odours from existing facilities, setting conditions for licensing of new facilities, quantification of rates of odour emmission before and after an upgrade of a facility has ocurred, for purposes of evaluating odour in the process of remedying a contaminated site and lastly for purposes of studies related to buffering in cases where the neighbouring land has not yet been sectored for metropolitan utilities (EPA Western Australia, 2002). For purposes of comparison of odour levels the various territories in Australia hve their own a set standards related to sampling and analyzing of odours. Odour has been recorded by DEP as the causing factor of about a third of all complaints made by the public in Australia that are related to pollution odour from water treatment plants being included in this category. Mainly, the problem of odour occurs due to unsuited land uses or in other words when subdivision of land close to effluent water disharge areas occurs due to the spread of development plans to areas initially regarded as rural (EPA Western Australia, 2002). There are four main scientific measurements of odour namely; Odour detection threshold: this is the least possible odorant concentration necessary for recognition by about 50% of the population and is usually distinct by one unit of odour Odour intensity: this is the perceived strenth of an odour in excess of its threshold. It is usually decided upon by an odour team and is usually depicted in groupings which advance from “not traceable” to “very weak” to “very strong” (Gostelow et al, 2000). Hedonic tone: this is the extent to which an odour is recognized as agreeable or disagreeable. The discernment of an odour as agreeable or disagreeable varies from one person to another and is mainly influenced by a large extent by factors such as sentiments, the time when the odour was apparent and preceding familiarity (Gostelow, Parsons, & Stuetz, Odour Measurements for Sewage Treatment Works, 2001). Odour Character: this is basically what the odour smells like. It is what enables a person to distinguish it from other odours. For instance, the character of ammonia’s odour is known to be overpowering and irritating. It is good to note that the character of an odour can be affected by dillution (Ministry of Environment New Zealand, 1995). Complaints about odour occur when individuals consider it to be intolerable and are to a large extend annoyed by it to warrant their action. There are five factors that influence such action from individuals in the community namely: the rate of recurrence of the odour, the strength of the odour, the period of contact with the odour, the unpleasantness of the odour and the locality of the odour (Gostelow et al, 2000). All the above factors are measurable and can be put together into guideline for purposes of regulating them. The unpleasantness of an odour is a subjective dactor and is closely related to an odour’s hedonic tone so it is quite complicated to measure. The key function of DEP is to guard the community from odours deemed to be reasonably offensive (in relation to their hedonic tone) and especially those that are connected with waste waterr treatment (effluent) which are the subject of this paper, among others. Chemical odours that emanate from heavy industry activities also belong to this groupd and and they equally need to be considered especially with reference to the impacts that they might have on human health and the environment. Due to the inconsistencies in historical standardized ways and terminologies of measuring odour, it is complicated to understand and contrast the odour measurements that are contained in literature (Hallier et al, 2004). The recently established Australian standards (alongside the international ones) are however likely to perk up the circumstances in future. Once the measurement s of odour are established, dispersion modelling can be utilized to determine the areas that is likely to be affected by the odour. Dispersion models are so many inexistence and they are capable of providing graphical representations which are in turn very helpful when it comes to correspondin gto the effects associated with a certain venture. This part will discuss two methods of odour measurement by use of dynamic olfactometry which is the most widely used method in Australia, and try to establish their advantages and disadvantages as well as problems associated with them. It will also compare them to other methods. Odour Concentration Thre are o practical instruments based methods for measueing a response to odour in the same way that the human nose can do it. Therefore, “dynamic olfactometry” is usually used as the foundation for odour supervision by any regulatory bodies. Dynamic olfactometry involves sampling of odourous air and presenting it to a panel of people at various points of dilution and finding out from the panel if they can detect the odour. The responses of the panel are then used to correlate those responses to the already established dilution ratios. The findings of the correlation are then used to compute the number of dilutions of the original sample that is needed to achieve the odour recognition intensity. Odour dynamic olfactometry is measured in odour units (OU). Odour units have no odour dimension and are basically the helpful “dilutions to threshold”. This method has undergone various improvements to ma”the draft Committé Européen de Normalisation (CEN) odour measurement standard of 1996”. This standard according to Van Harreveld & Dönszelmann (1994), was laboratory tested and was proved to be efficient to the points of efficiencies associated with noise dimensions. However anyone taking odour emasurements using the dynamic olfactometry method should note that its different methods give different results for odour threshold; therefore, any use of available odour thresholds in print must be scrutinized for the methodology used and for the necessary tuning features before being used. This is per the regulations of DEP in Australia. It is also important to note that DEP favors “the Dutch NVN 2820” which is known to gives a odor threshold that is double in terms of odour units as compared to the Victorian EPA B2 which is the method tested in Victorian EPA Labs (Badsley & Demetriou, 1997). Odour Intensity Odour intensity as escribed above is expressed in term such as “not traceable”, “weak” or “strong”, etc. The German Olfactometry based standard of measuring odour intensity, “the VDI 3882 Part 1” according to Verein Deutscher Ingenieure "VDI" (1992), gives a qualitative account of how to describe odour intensity by means of a arithmetic range that can be utilized in back-computing of analogous concentration. Thes are shown in the table below; Odoour Strength Intensity Level Extremely Strong Very Strong Strong Distinct Weak Very Weak Noe Traceable 6 5 4 3 2 1 0 Just like odour thresholdverification, odour intensity is measured in a laboratoryby a panel and dymanic olfactometry laboratory methods. An odour concentration that is greater than the odour threshold (one unit of odour or 1 OU/m3) is offered to a panel of people who rate the strength of the odour as per the table above and since the odour threshold is already known the level of dilution of th eodour is controlled by use of equipment. Its is widely accepted that a “distinct” odour or an odour whose intensity is at the same level as its concentration threshold might just be able to be realized in this manner which is very hard to detect in the environment. The following standards of measurement of odour concentration are recognized by in Australia: “ The Dutch Standard NVN 2820 of 1995, CEN olfactometry, CEN TC264/WG2 ‘Odours’ Final WG2 Draft prEN OF 1995, Australian Standard 4323.3:2001which is also based on CEN standards and The German Standard VDI 3882 Part” (Note technique Odotech #ODO 2007-25, 2007 ;Standards Australia / Standards New Zealand, 2001). Problems associated with the odour concentration and odour intensity methods - There are no standard methods for measuring odour concentration and odour intensity from renegade sources as the above methods only apply to point and non point sources only. - The measurement of the threshold factor creates a methodological risk in the least “sense modality” because when operating in the midst of limitations of human sensitivity, it is very likely that contamination will cause inconsistencies as compared to measures of “suprathreshold” magnitude which often seeks to compare sensitivity to odour between different people (Gostelow, Parsons, & Stuetz, 2000). - Sample contamination could cause a wrong result - Human limitations: Presentation of odours to the panel in a descending order (from strong odour to weak odour) could cause an enhancement in the effects of “adsorption/desorption” and it could also lead to olfactory alteration in panellists since a weak odour (highly diluted) is harder to detect after a person has already been exposed to strong odour (lower dilution) (Standards Australia / Standards New Zealand, 2001). - Another factor that limits the olfactometric method which is also human related is the facts that the sensitivity to odours varies from one individual to another and so inconsistencies are likely to occur for the same sample from different panellists. Conclusion All in all, developments in odour evaluation and policy are ongoing with various territories in Australia coming up with their own criteria. List of References Badsley, T., & Demetriou, J. (1997). Odour Measurements That Don’t Stink . Sydney: National Workshop on Odour Measurement Standardisation. EPA NSW. (2001). Draft Policy: Assessment and Management of Odour from Stationary Sources in NSW. Sydney: EPA NSW. EPA Western Australia. (2002). Guidance for the Assessment of Environmental Factors – Assessment of Odour Impacts from New Proposals – No. 47. Perth: EPA Western Australia. Gostelow, P., Parsons, S., & Stuetz, R. (2001). Odour Measurements for Sewage Treatment Works. Water Research Vol 35 Issue 3 , 579-597. Gostelow, P., Parsons, S., & Stuetz, R. (2000). Sewage treatment works odour measurements. Wat. Sci.Technol. Vol. 41 Issue 6 , 33-40. Hallier, A., Courcoux, P., & al, e. (2004). New gas chromatography–olfactometric investigative method, and its application to cooked Silurus glanis (European catfish) odor characterization. Journal of Chromatography A Vol 1056 , 201-208. Ministry of Environment New Zealand. (1995). Odour Management under the Resource Management Act. Wellington: Ministry of Environment New Zealand. Note technique Odotech #ODO 2007-25. (2007). Non-validité de l’échantillonnage discontinu d’odeur en air Non-validité de l’échantillonnage discontinu d’odeur en air. Barnéoud P., Leduc R . Standards Australia / Standards New Zealand. (2001). Australian / New Zealand Standard 4323.3 Stationary source emissions – Part 3: Determination of Odour Concentration by Dynamic Olfactometry. Sydney: Standards Australia / Standards New Zealand. Van Harreveld, A., & Dönszelmann, C. (1994). Odour Nuisance: policy options and regulatory approach. Welsh: Chartered Institute of Environmental Health. Verein Deutscher Ingenieure "VDI". (1992). Olfactometry Determination of Odour Intensity - VDI 3882 Part 1. Retrieved August 26, 2012, from Verein Deutscher Ingenieure, Düsseldorf: http://www.beuth.de Read More

Water quality values in Australia are usually based upon considerations of the active ecology, the ecological values that are attributed to the use of the recipient water, the ecological current , among other community based goals. This paper aims at describing methods which could be used to measure the disbenefits that are caused by the release of effluent into the environment with specific reference to odour that emanates from this effluent substances. It will seek to explain how these methods operate as well as their values.

The paper will also seek to establish the problems that are connected with thse ways and the advantages that they may hold over other methods. Discussion The Department of Environmental Protection (DEP) has the responsibility of dealing with complaits related to odour that affect the amenities of the commuities in Australia. The environmental Protection Act of 1996 particularly takes care of “Unreasonable emissions” which include emissions of noise, odour, and electromagnetic radition which irrationally impede on the health, wellbeing, calm, expediency or properties of people within a community.

The standards of identifying what is unreasonable are supposed to be determined for each case since they differ from one case to the other (EPA NSW, 2001). Odour is particularly an issue in places where there are differences of land use which often results in receptives being situated near the source of the odour. The EPA guideline no. 47 on the assessment of odour impacts, calls for innovative suggestions and extension of available amenities. Odour guidelines related to existing facilities will however always be different for different situations (EPA Western Australia, 2002).

The measurement of odours could be used to evaluate a variety of circumstances including; creating new facilities to manage odours or expanding on existing ones, coming up with ways of using land sensitively in an existing facility, looking into complaints of odour brought to DEP regarding odours from existing facilities, setting conditions for licensing of new facilities, quantification of rates of odour emmission before and after an upgrade of a facility has ocurred, for purposes of evaluating odour in the process of remedying a contaminated site and lastly for purposes of studies related to buffering in cases where the neighbouring land has not yet been sectored for metropolitan utilities (EPA Western Australia, 2002).

For purposes of comparison of odour levels the various territories in Australia hve their own a set standards related to sampling and analyzing of odours. Odour has been recorded by DEP as the causing factor of about a third of all complaints made by the public in Australia that are related to pollution odour from water treatment plants being included in this category. Mainly, the problem of odour occurs due to unsuited land uses or in other words when subdivision of land close to effluent water disharge areas occurs due to the spread of development plans to areas initially regarded as rural (EPA Western Australia, 2002).

There are four main scientific measurements of odour namely; Odour detection threshold: this is the least possible odorant concentration necessary for recognition by about 50% of the population and is usually distinct by one unit of odour Odour intensity: this is the perceived strenth of an odour in excess of its threshold. It is usually decided upon by an odour team and is usually depicted in groupings which advance from “not traceable” to “very weak” to “very strong” (Gostelow et al, 2000).

Hedonic tone: this is the extent to which an odour is recognized as agreeable or disagreeable. The discernment of an odour as agreeable or disagreeable varies from one person to another and is mainly influenced by a large extent by factors such as sentiments, the time when the odour was apparent and preceding familiarity (Gostelow, Parsons, & Stuetz, Odour Measurements for Sewage Treatment Works, 2001).

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