brownfield site development case study

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• Published: 16 October 2023

Brownfield redevelopment evaluation based on structure-process-outcome theory and continuous ordered weighted averaging operator-topology method

• He Jian 1 ,
• Jiang Haidan 1 ,
• Pan Haize 2 &
• Liu Chuan 2  

Scientific Reports volume  13 , Article number:  17530 ( 2023 ) Cite this article

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• Engineering
• Environmental sciences
• Environmental social sciences
• Mathematics and computing

As an important part of urban renewal, brownfield restoration and renovation are of great significance to the sustainable development of cities. The structure-process-outcome theory was introduced into this study to improve the rationality and scientific vigor of the redevelopment assessment process and to evaluate whether brownfield sites meet the conditions for redevelopment. Based on this theory, the relationship among structures, processes and outcomes can be well elucidated. Specifically, a good structure should contribute to an effective process, which will increase the possibility of a favorable outcome. The basic conditions, practice principles, and result orientation in the whole procedure of brownfield redevelopment were comprehensively analyzed. In addition, a more complete and reasonable three-level evaluation index system for brownfield redevelopment was established. In order to reduce the subjectivity in the evaluation process, an unbiased scientific brownfield redevelopment evaluation model was constructed using the continuous ordered weighted averaging operator-topology method. The evaluation decision system was applied to the renovation of a tract project in Chengdu, China. The results proved that the model could effectively and accurately evaluate the quality level of the brownfield redevelopment project, and the proposed recommendations can provide a basis for decision-making.

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Introduction.

The term “brownfield” was widely used in Western countries after being proposed at a hearing in the U.S. Congress in June 1992. According to the United States Environmental Protection Agency (USEPA), brownfields are defined as lands that are developed, partially or fully utilized, as well as those that are unused, potentially contaminated, and difficult to redevelop 1 .

With the ongoing urbanization and industrialization of China, the scale of cities and urban population has increased dramatically. The rapidly rising demand for urban construction land has greatly intensified the pressure on land supply. During the 40 years of reform and opening up, the urbanization rate of China rose rapidly from 17.92% in 1978 to 64.7% in 2021, and the urban land demand increased 4.72 times from 12,856 km 2 in 1990 to 60,721 km 2 in 2020 2 . However, with the closure and relocation of historical industrial areas, the number of brownfields has shown a trend of yearly increase, and urban wasteland is also on the upswing. In 2012, China reported approximately 300,000 brownfields covering a total area of about 20 million hm 2 3 . In 2014, there were about 4.2 million brownfield sites in the EU, 340,000 of which were at risk of contamination 4 . In 2018, there were over 450,000 estimated developable brownfield sites in the United States. In 2020, there were 21,000 estimated brownfield sites in England, which could transform into 1.06 million households after redevelopment 5 . The emergence of brownfields is indicative of land resource waste, causes potential environmental pollution and leads to the decline of urban life quality. Therefore, in order to realize the full utilization of urban land resources and improve the urban living environment, the restoration and redevelopment of brownfield is imperative.

In order to fully utilize the construction land and protect the environment, the Chinese Ministry of Land and Resources issued the Regulations on the Economical and Intensive Use of Land in May 2014 6 . In November 2016, the Ministry of Land and Resources issued the Guiding Opinions on Further Promoting the Redevelopment of Low-Use Land in Urban Areas 7 . The focus on urban land use has gradually shifted from “incremental” to “stock”. In December 2016, the Chinese Ministry of Environmental Protection promulgated the Measures for Soil Environmental Management of Contaminated Land 8 . In 2017, Chinese provinces began to publish a list of risk control measures for contaminated land, and the management and redevelopment of brownfields began to receive attention 9 . In 2020, Chinese President Xi Jinping delivered an important speech at the 75th General Debate of the United Nations General Assembly, setting out the goal and vision for China to strive to reach peak carbon emissions by 2030 and achieve carbon neutrality by 2060. Green development has become an inherent requirement for high-quality urban development. However, there are a series of obstacles to redeveloping and utilizing brownfield sites. It is also difficult to understand the economic benefits of redeveloping brownfield sites due to their superior location, pollution issues, high costs, and the involvement of numerous stakeholders.

This paper aims at the ex-ante evaluation of brownfield redevelopment and the assessment of whether brownfield sites meet the conditions for redevelopment. It also focuses on addressing the issues concerning the rationality and scientific vigor of the redevelopment assessment process. In the second part of this paper, we reviewed the research on brownfield development worldwide and pointed out the research gap. In the third section, a brownfield redevelopment evaluation index system was developed based on the structure-process-outcome theory. In the fourth part, a brownfield redevelopment evaluation model was constructed based on the continuous ordered weighted averaging (C-OWA) operator-topology method, and the fifth part is a case analysis, which verifies the applicability of the evaluation indexes and the evaluation model. The evaluation indexes and evaluation models proposed in this study are more comprehensive, reliable and applicable and provide a good basis for the decision-making related to brownfield redevelopment.

Literature review

As an important land section in urban development, the economic and social benefits of brownfields have received extensive attention. In 2006, Shen 10 underscored the importance of the reuse of “brownfields” in the transformation of resource-based cities. By combining brownfields with the construction of urban green space networks, new impetus can be generated for sustainable urban development. In 2010, Adams 11 stated that brownfields should be considered as a development opportunity rather than a planning issue. In 2017, Ni 12 pointed out that brownfield regeneration is an important way for sustainable urban development and an important source of urban green open space. In 2018, Naveed 13 stated that the identification and assessment of brownfields are necessary to address environmental issues and promote sustainable development. Based on a survey of 200 brownfield sites in the United States from 2000 to 2015, Green 14 concluded that socioeconomic factors (income levels), green development, and tax incentives are significantly associated with brownfield redevelopment. In 2019, Zhao and Zang 15 pointed out that the location of brownfield sites significantly influences investors’ decisions and brownfield regeneration in the urban renewal process. In 2020, Zhong et al. 16 proposed a conceptual framework for ex-ante evaluation of brownfield greening based on ecosystem services assessment, economic cost–benefit analysis, and spatial pattern analysis. Based on a survey of brownfield redevelopment decision systems over the past 20 years, Hammond et al. 17 argued that these decision systems fall short in addressing the complexity of brownfields from a sustainability perspective. The above studies illustrate that brownfield redevelopment has a significant impact on developing high-quality, green, and sustainable cities. However, it is difficult to determine whether a brownfield meets the development standards because of the possibility of contamination and the complicated surrounding environment. Therefore, a thorough pre-evaluation is crucial to guarantee the effectiveness of the redevelopment project. Accordingly, this paper introduces the structure-process-outcome theory to the assessment of brownfield redevelopment. Based on this theory, the relationship among structure, process, and outcome can be clearly elucidated. Specifically, a good structure should promote an effective process, and an effective process will increase the likelihood of an ideal outcome. In addition, a more thorough evaluation index system from the dimensions of structure, process, and outcome can be established. In order to reduce the subjectivity in the evaluation process, the C-OWA operator-topology method is applied to establish the brownfield redevelopment evaluation model. Its applicability, scientific vigor, and rationality are verified in practical cases. The results show that the evaluation system provides a good basis for decision-making on brownfield redevelopment.

Establishment of Brownfield redevelopment evaluation index system

Structure-process-outcome theory.

In 1966, Donabedian argued that the quality of medical care services should be understood as the expectation that comprehensive and rational medical services can fulfill the physical and mental health goals of patients 18 , 19 , 20 . In addition, the classical quality evaluation model of structure-process-outcome was proposed, which aimed to evaluate healthcare service quality with an emphasis on context, actions and effects. Structure refers to the original basic conditions in the organization, including hardware and software facilities for service delivery, human and material input, and other objective resources. Process refers to the services provided to clients in a specific process, including physical and psychological care, training of staff, and monitoring of the process and other implementation measures. The outcome is the desired state after receiving the service. It is also the feedback on the structure and process, such as the physical and mental changes and service satisfaction. “Structure-process-outcome” is a holistic system with complex interrelationships that do not present a simple linear pattern. The structure is static, and the process is dynamic. The quality of structure and process inevitably affects the outcome, with the process exerting a more direct impact. Therefore, good structure and process can positively contribute to the outcome 21 , 22 , 23 , 24 .

Based on the three dimensions, namely, “structure, process, and outcome”, the whole procedure of the brownfield development process is analyzed. The influencing factors are studied, and the information elements are examined to form a more scientific and comprehensive evaluation index system for brownfield redevelopment 25 , 26 .

Metrics construction process

The structural dimension measures all physical infrastructure conditions related to brownfield sites in the redevelopment process 27 . In terms of brownfield conditions, the degree and type of pollution affect the difficulty of environmental remediation. The location, size, and traffic conditions of brownfield sites impact the value of investments. Moreover, human factors such as literacy, income level, and the relationship between neighbors also determine the difficulty of the redevelopment process. Therefore, accurate information on the structural dimensions of brownfields is the basis for redevelopment management.

The process dimension mainly refers to practical principles, human decision-making management, and organizational coordination of the brownfield redevelopment process. In the process of brownfield redevelopment, capital investment (e.g., environmental remediation and renovation construction costs), matching measures (e.g., regional planning, government policy support and supervision, and management), basic conditions of construction and renovation enterprises, and public opinion guidance (e.g., access to environmental information) significantly affect the process of brownfield redevelopment. Therefore, coordinating the relevant interests of all participants is the key to the success of the project 28 .

There are two main sources of funding for project implementation: the government and social capital. The outcome orientation is the main factor considered by investors. Therefore, the outcome dimension mainly involves measuring the economic and social benefits of brownfield redevelopment projects. Economic benefits include expected revenue and the length of the payback period, and the social benefits are the satisfaction of the surrounding residents and the added value of the surrounding area 29 .

Based on the three dimensions, relevant studies, and expert consultation, the evaluation index system for brownfield redevelopment is established, as shown in Table 1 .

C-OWA operator-topological evaluation model

Calculation of index weights of c-owa operator.

Due to excessive evaluation indexes, cross-influence of indexes, different expert perceptions, and personal preferences, the disturbance of subjective emotional factors in weight assignment by the traditional hierarchical analysis method, entropy method, or factor analysis method is unavoidable, significantly affecting scientific validity 30 . Due to the characteristic resembling a normal distribution and the close relevance to the decision data, the C-OWA operator method proposed by Professor Yager in 2004 is widely used in decision-making management. With this method, the subjectivity of the weight calculation can be avoided, and the fairness of the decision-making can be enhanced. The C-OWA operator weighting method can contribute to a rational and scientifically robust evaluation of brownfield redevelopment and solve the intricacies arising from the involvement of a large number of evaluation indexes, the need for modeling, and the uncertainty in the index data 31 .

Establishing the initial evaluation matrix

Experts were invited to score by the Delphi method on a scale of 1–10. According to relevant studies 32 , 33 , 34 , the importance scores of brownfield redevelopment evaluation indexes were divided into five levels, with [9,10) representing level I (extremely important), [8,9) indicating level II (very important), [7,8) representing level III (quite important), [6,7) representing level IV (somewhat important), and [0,6] indicating level V (not important). The initial evaluation matrix \(A\left( {a_{1} ,a_{2} , \ldots ,a_{n} } \right)\) was obtained and then sorted in the order of scores from largest to smallest to yield \(B\left( {b_{0} ,b_{1} , \ldots ,b_{n - 1} } \right)\) , where \(b_{0} > b_{1} > b_{2} > \cdots > b_{n - 1}\) .

Calculation of the weighted vector

The weighted vector \(\chi_{j + 1}\) about the vector \(B\) is calculated through the following equation:

where \(\sum\nolimits_{j = 0}^{m - 1} {\chi_{j + 1} } = 1\) and \(j = 0,\;1,\;2 \ldots ,m - 1\) ; \(m\) is the number of experts.

Calculation of the absolute weight

The absolute weight \(\varpi_{i}\) of each index factor \(i\) is calculated by the weighted vector \(\chi_{j + 1}\) :

where \(i = 0,1,2 \ldots ,n\) ; \(n\) is the number of indexes.

Calculation of relative weight

The relative weight \(\omega_{i}\) of each index factor \(i\) is calculated by the absolute weight \(\varpi_{i}\) :

Topologically integrated evaluation model

Topologism was proposed by Wen 35 in 1983. It is an innovative method to explore expansion with a formal model for solving contradiction. Currently, topology is widely used in many fields, such as engineering, management, economics, and philosophy, and it combines qualitative and quantitative approaches 36 . The introduction of the comprehensive evaluation model based on the concept of topology will facilitate the hierarchical representation of the quality level of brownfield redevelopment, clarify the evaluation level of each index factor in a formal and organized manner, and guide the decision-making related to brownfield redevelopment, the matters that should be paid attention to, and the corresponding countermeasures.

Determination of the classical domain, the section domain, and object elements

According to the topological theory, the characteristics, quantitative values, objects, and changes of the contradictory problems of brownfield redevelopment quality evaluation can be expressed based on the topological distance. The primitives (characteristics, quantitative values, objects) are established to classify the brownfield redevelopment quality evaluation into classical and nodal domains 37 .

A certain level of rating index corresponding to the quality evaluation of brownfield redevelopment and the value interval is considered the classical domain \(R_{i}\) , which can be expressed as follows:

where \(N_{i}\) is the \(i\) th evaluation level of brownfield redevelopment quality evaluation; \(C_{j}\) is the evaluation index; \(V_{ij}\) is the value range of the corresponding evaluation index.

The nodal domain \(R_{P}\) is determined with the following equation:

where \(N_{p}\) is all grades of brownfield redevelopment quality evaluation; \(C_{j}\) is the evaluation index; \(V_{pj}\) is the value range of the corresponding evaluation index.

The primitive \(R_{x}\) is determined with the following equation:

where \(P\) is the unit number; \(C_{j}\) is the evaluation index; \(V_{j}\) is the value of the corresponding evaluation index.

Determination of the association function

Calculation of the topologizable distance. Based on the classical domain and the nodal domain, the topologizable distance between each evaluation index of the primitive and the classical domain and the nodal domain can be calculated as follows:

Calculation of correlation degree. The correlation degree reflects the correlation between the evaluation indexes and each evaluation level, which can be expressed as follows:

Calculation of the total correlation degree. Based on the value \(K_{ti} (V_{ij} )\) of the correlation degree of each index evaluation level \(i\) and the corresponding weight value \(\omega_{j}\) , the total correlation degree \(K_{j} (N_{j} )\) can be obtained:

According to the principle of maximum membership \(K_{j0} (N_{j} ) = \mathop {\max }\nolimits_{{j \in \left( {1,2, \cdots ,m} \right)}} K_{j} (N_{j} )\) , the grade of the redevelopment quality of the brownfield can be obtained 38 .

Project overview

Sanxiang Reconstruction Project is located at the junction of the old and new city on Guihu East Road, Xindu District, Chengdu City, Sichuan Province, China. The area is well-equipped with infrastructure and medical facilities. It belongs to the core of the city, with convenient transportation, developed businesses and abundant educational resources. The area was built in the 1980s, mainly for residence, involving nine old neighborhoods. Most houses are resettlement houses, and some are small factories and workshops. Over the years, the area has suffered from outdated facilities, backward management, poor sanitation, lack of service support and poor overall appearance due to local characteristics, such as dense buildings and population, narrow roads and space, and mixed pedestrian and vehicles. In addition, some of the building entrances are dilapidated, and the terrain is prone to waterlogging. Fitness and recreational facilities for residents are outdated and missing, and some owners occupy public space for private construction. These problems have seriously affected the normal life of residents.

In recent years, the government began to vigorously renovate old urban courtyards to reasonably use urban space and prevent and resolve major security risks. It has also focused on improving the living environment, making up for functional shortcomings, and improving governance services, thus creating a harmonious community with a more beautiful environment, complete functions, and convenient living. Since 2023, the area has been included in the list of renovation and upgrading.

Calculation of index weights by C-OWA operator

To evaluate the feasibility of redeveloping this brownfield site, influencing factors were scored (1 to 10) according to the established evaluation index system, with higher scores indicating greater importance. Six experts from different backgrounds, including government, environmental, construction, development, academic and consulting sectors, were invited to score the importance of the indexes. The final scores obtained are shown in Tables 2 , 3 and 4 .

Calculation of primary index weights

The expert scores of the primary indexes were obtained, as shown in Table 2 .

The weights were calculated using structural indexes as an example, and the score results were reordered from largest to smallest:

The weight of each data was calculated according to Eq. ( 1 ):

The absolute weights of indexes were calculated by Eq. ( 2 ):

The relative weight of each index was obtained by Eq. ( 3 ):

Calculation of secondary index weights

The expert scores of the secondary indexes were obtained, as shown in Table 3 .

The calculation of absolute weights is consistent with that of the primary index weights, and the results are as follows:

The relative weights of the indexes are:

Calculation of three-level index weights

The expert scores of the three-level indexes were obtained, as shown in Table 4 .

Similar to the first two levels, the absolute weight can be obtained as follows:

Quality evaluation of brownfield redevelopment based on the topology method

Element determination of classical domain, section domain and object to be evaluated.

Each three-level index S 111 , S 112 , …, O 311 , O 312 were assigned as \(c_{1} \sim c_{27}\) , and the classical domain of level I is:

Similarly, the classical domain \(R_{2}\) , \(R_{3}\) , \(R_{4}\) and \(R_{5}\) of each level can be obtained.

Section domain \(R_{0}\)

Ten people were invited to score the project according to its basic characteristics, with a scale of 1–100, where [90,100) is I excellent, [80, 90) is II good, [70, 80) is III moderate, [60, 70) is IV qualified, [0, 60] is V unqualified. The maximum and minimum values of the experts’ scores were removed to calculate the average, and the specific value \(R_{x}\) of the elements to be evaluated was obtained, as shown in Table 5 .

Correlation calculation

Taking the three-level index S 111 as an example, the correlation was found by combining Eqs. ( 7 ) and ( 8 ):

It can be seen from \(K_{j0} (c_{1} ) = \mathop {\max }\nolimits_{{j \in \left( {1,2, \cdots ,m} \right)}} K_{j} (c_{1} )\) that the brownfield location condition S 111 is Level I excellent. Similarly, the correlation of all indexes at the three levels can be calculated, as shown in Table 6 .

Comprehensive evaluation

The correlation of primary indexes and secondary indexes was calculated by Eq. ( 9 ) and \(K_{j0} (c_{1} ) = \mathop {\max }\nolimits_{{j \in \left( {1,2, \ldots ,m} \right)}} K_{j} (c_{1} )\) , as shown in Tables 7 and 8 . Then, the integrated correlation of brownfields in the overall development quality evaluation was calculated:

Evaluation results and analysis

According to the maximum affiliation principle \(K_{j0} (O) = \mathop {\max }\nolimits_{{j \in \left( {1,2, \ldots ,m} \right)}} K_{j} (O_{j} ) = - \;0.0729\) , the overall quality evaluation rating for the redevelopment of this brownfield project is II good, indicating that the site is suitable for development. The correlation of the primary indexes shows that the process quality and outcome indexes are both II good, but the quality of the structure indexes scores V unqualified.

All secondary indexes under the process index are II good, indicating that government policy support, process supervision and management, transparent and open information, technical guarantee from experts, and capital investment have significant advantages in the renovation project. It also shows that all participants strongly support the renovation project in the early stage.

All secondary indexes under the outcome index are also II good, indicating that the project has great benefits in both social and economic aspects and also revealing that residents are paying more and more attention to the environment and demanding a higher quality of life.

The geographic environments, human conditions and pollution conditions under the structural indexes are all evaluated as V unqualified. Specifically, the low evaluation of geographic environments is mainly caused by the low three-level index rating of use status and traffic conditions, which indicates that the current land use of the project is chaotic and unreasonable; traffic jam is severe despite the superior location. The low evaluation of human conditions is mainly caused by the low knowledge level of the three-level index of the brownfield, and the low evaluation of pollution conditions is mainly caused by the low knowledge level of the brownfield. The low assessment of the pollution condition is mainly caused by the large challenges in restoration technology. Therefore, we need to carefully consider the use and traffic planning of the renovated project. Transparency and openness in information dissemination are essential to raise public awareness of the hazards of brownfield sites and gain public support.

The secondary indexes of geographic environments, human conditions and pollution status under the structural indexes are all evaluated as V unqualified. Specifically, the low evaluation of geographic environments is mainly caused by the low three-level index rating of use status and traffic status, indicating that the current land use of the project is chaotic and unreasonable; traffic congestion is severe despite its superior location. The low evaluation of human conditions is mainly caused by the low environmental awareness of brownfield sites of three-level indexes. The low evaluation of pollution status is mainly caused by the large challenges in restoration technology. Therefore, the use and traffic planning of the renovated project should be considered carefully and comprehensively. Information should be transparent and open to raise public awareness of the hazards of brownfield sites and gain public support. In addition, technical efforts should be further concentrated to overcome difficulties and ensure adequate technical support for project implementation.

With the expansion of urbanization, brownfield redevelopment projects in the process of urban renewal have become an important guarantee for green and sustainable urban development, alleviating the land tension for urban development and improving urban quality. Brownfield redevelopment is often challenged by complex issues such as environmental governance, the involvement of multiple stakeholders and high economic investment. Therefore, the main objective of this study is to form a scientific and reasonable ex-ante evaluation mechanism for brownfield redevelopment.

Firstly, in order to establish a reasonable evaluation index, this study introduces the structure-process-outcome theory, from the perspective of green sustainability, a comprehensive analysis of the basic conditions, practice principles and outcome orientation throughout the brownfield redevelopment is conducted from three dimensions: structure, process and outcome. The composition of influencing factors under each dimension is studied, and the composition of information elements under the interconnection of each dimension is analyzed. A complete evaluation index system of brownfield redevelopment is established by combining literature review and expert consultation, including three primary indexes, nine secondary indexes and 27 three-level indexes.

Secondly, to obtain a scientific computational model, the C-OWA operator assignment method, which is closely related to the decision data and has the good nature of normal distribution, is applied to the weight calculation of the index system of brownfield redevelopment. Its adoption eliminates the subjectivity of weight calculation and reflects the fairness of decision-making. The characteristics, quantitative values, objects and changes of the contradictory problems in brownfield redevelopment evaluation are effectively expressed by incorporating the topologic theory. The organic combination of the two enables scientific and reasonable modeling of brownfield redevelopment evaluation.

Finally, to validate the applicability of the evaluation mechanism. Brownfield redevelopment evaluation indexes and evaluation models are applied to Sanxiang Reconstruction Project. The evaluation results obtained that the total quality evaluation grade of the redevelopment of this brownfield project is Class II good, very suitable for development. However, the geographic environment, human conditions and pollution status of each secondary indicator evaluation are level V failed. Based on the results of the assessment, the following policy recommendations are made. First, effective planning should be done in the process of brownfield development, and brownfield development efforts should align with the surrounding environment. Second, the dissemination of brownfield knowledge in a transparent manner should be given priority to raise public awareness regarding the hazards of brownfield sites and to gain public support. The recommendation was fed back to the project decision makers and contributed well to the smooth running of the brownfield project.

It can be found through the above study that the brownfield redevelopment evaluation mechanism proposed in this paper has great practical significance, the use of the C-OWA operator-topology method can effectively reduce subjectivity in the evaluation process, but there remains a lack of clarity and uncertainty in the majority of the indicators. In the future, we will concentrate on optimizing the indicators and gathering more data to further increase the objectivity and plausibility of the evaluation results.

Data availability

All data used in this study are available from the corresponding author.

He, J., Pan, H., Chen, M. & Miao, W. Study on sustainable development of brownfield sites in China based on LEED-NC. J. Hunan Ecol. Sci. 2 (4), 34–39 (2015).

Google Scholar  

Sun, T. Reflections on the dominant strategies and practices of urbanization development in China in the past 40 years [J/OL]. Lingnan J. 2023 , 1–9. https://doi.org/10.13977/j.cnki.lnxk.2023.01.004 (2023).

Article   Google Scholar  

Fei, L. V. & Tingting, Yu. Study on urban brownfield transformation in China based on Landscape Urbanism: Taking the landscape transformation of prosperous block section of Majiagou in Harbin as an example. Chin. Garden 3 , 68–73 (2014).

Van Liedekerke, M., Prokop, G., Rabl-Berger, S, Kibblewhite, M. & Louwagie, G. Progress in the Management of Contaminated Sites in Europe (2014). https://doi.org/10.2788/4658 .

CPRE. Recycling Our Land: The State of Brownfield 2020—An Updated Analysis of the Potential of Brownfield Land for New Homes https://www.cpre.org.uk/wp-content/uploads/2020/10/Recycling-our-land-the-state-of-brownfield-report-Oct-2020.pdf (2020).

The Central People's Government of the People's Republic of China (2023, accessed 10 Feb 2023). http://www.gov.cn/zhengce/2019-08/13/content_5711405.htm .

Ministry of Natural Resources of the People 's Republic of China (2023, accessed 10 Feb 2023). https://www.mnr.gov.cn/dt/zb/2016/czh/zhibozhaiyao/201806/t20180629_1964679.html .

GreenPeace; Lishui Institute of Ecological Environment, Nanjing University. Problems and Countermeasures in the Development and Utilization of Urban Polluted Land in China (2023, accessed 5 Feb 2023). https://www.greenpeace.org.cn/redeveloping-the-polluted-land-under-chinas-cities-problems-and-solutionsreport/ .

Jian, H. et al. Research on brownfield redevelopment based on Wuli-Shili-Renli system theory and catastrophe progression method. PLoS ONE 17 (11), e0277324. https://doi.org/10.1371/journal.pone.0277324 (2022).

Article   CAS   PubMed   PubMed Central   Google Scholar  

Jin, S. & Tiezheng, Z. Brownfield and green space network–spatial reuse of Tangshan Nanhu coal mining subsidence area. J. Archit. 08 , 28–30 (2006).

Adams, D., De Sousa, C. & Tiesdell, S. Brownfield development: A comparison of North American and British approaches. Urban Stud. 47 (1), 75–104. https://doi.org/10.1177/0042098009346868 (2010).

Ni, M., Chen, Z. & Zuo, W. Urban design strategies for ecological areas under the concept of “urban double repair”—take Ningbo Xiaoyujiang area as an example. Planner 33 (3), 31–36 (2017).

Ahmad, N. et al. Development of a standard brownfield definition, guidelines, and evaluation index system for brownfield redevelopment in developing countries: The case of Pakistan. Sustainability 10 (12), 4347. https://doi.org/10.3390/su10124347 (2018).

Green, T. L. Evaluating predictors for brownfield redevelopment. Land Use Policy 73 , 299–319. https://doi.org/10.1016/j.landusepol.2018.01.008 (2018).

Yabo, Z., Peng, Z. & Xuemei, Z. Recent progress of urban renewal research at home and abroad. Urban Dev. Res. 26 (10), 42–48 (2019).

Zhong, Q. et al. A conceptual framework for ex ante valuation of ecosystem services of brownfield greening from a systematic perspective. Ecosyst. Health Sustain. 6 (1), 1743206. https://doi.org/10.1080/20964129.2020.1743206 (2020).

Hammond, E. B. et al. A critical review of decision support systems for brownfield redevelopment. Sci. Total Env. 785 , 147132. https://doi.org/10.1016/j.scitoten (2021).

Article   CAS   Google Scholar  

The Milbank Memorial Fund Quarterly, Vol. 44, No. 3, Part 2: Health Services Research I. A Series of Papers Commissioned by the Health Services Research Study Section of the United States Public Health Service. In Discussed at a Conference Held in Chicago 166–206 (1966).

Donabedian, A. The Definition of Quality and Approaches to its Assessment 28–45 (Health Administration Press, 1980).

Donabedian, A. The quality of care: How can it be assessed?. JAMA 260 (12), 1743–1748 (1988).

Article   CAS   PubMed   Google Scholar  

Kobayashi, H., Takemura, Y. & Kanda, K. Patient perception of nursing service quality; an applied model of Donabedian’s structure-process-outcome approach theory. Scand. J. Caring Sci. 25 (3), 419–425. https://doi.org/10.1111/j.1471-6712.2010.00836.x (2010).

Article   PubMed   Google Scholar  

Tossaint-Schoenmakers, R., Versluis, A., Chavannes, N., Talboom-Kamp, E. & Kasteleyn, M. The challenge of integrating eHealth into health care: Systematic literature review of the Donabedian model of structure, process, and outcome. J. Med. Internet Res. 23 (5), e27180. https://doi.org/10.1111/j.1471-6712.2010.00836.x (2021).

Article   PubMed   PubMed Central   Google Scholar  

Jing, Wu. An investigation of the organizational characteristics of pediatric ICU nursing in tertiary hospitals based on structure-process-outcome theory. Shanghai Jiaotong Univ. https://doi.org/10.27307/d.cnki.gsjtu.2019.002273 (2019).

Xiaogang, Ye. Research on research credit evaluation system for project leaders based on structure-process-result theory. Sci. Technol. Innov. Dev. Strategy Res. 4 (04), 53–58 (2020).

Jinjin, Ge., Weiqun, L., Changying, J., Yingyan, L. & Bo, H. Research on the construction of community nursing quality control index system in Shanghai based on structure-process-outcome theory. Chin. General Med. 17 (04), 609–613. https://doi.org/10.16766/j.cnki.issn.1674-4152.000748 (2019).

Zhu, Y. et al. Establishment and optimization of an evaluation index system for brownfield redevelopment projects: An empirical study. Environ. Modell. Softw. 74 , 173–182. https://doi.org/10.1016/j.envsoft.2015.09.012 (2015).

Szabó, M. & Bozsoki, F. Redevelopment of Brownfields for cultural use from ERDF fund—the case of Hungary between 2014 and 2020. J. Risk Financ. Manag. 15 (4), 181. https://doi.org/10.3390/jrfm15040181 (2022).

Tang, C., Wang, A. & Yan, J. Exploring motivations and resistances for implementing shared decision-making in clinical practice: A systematic review based on a structure-process-outcome model. Health Expect. 25 (4), 1254–1268 (2022).

Jiang, L. et al. Research on the methodology of day surgery quality and safety evaluation index system based on structure-process-outcome theory. West China Med. 04 , 581–585 (2022).

Yanbing, G. & Xuechun, L. A fuzzy multi-attribute decision making method based on fuzzy C-OWA operator. Syst. Eng. Electron. Technol. 08 , 1478–1480 (2008).

MATH   Google Scholar  

Xu, Z. Extended C-OWA operator and its application in uncertain multi-attribute decision making. Syst. Eng. Theory Pract. 11 , 9–15 (2005).

Sun, S., Chen, Y., Wang, A. & Liu, X. An evaluation model of carbon emission reduction effect of prefabricated buildings based on cloud model from the perspective of construction supply chain. Buildings 12 , 10 (2022).

Jinshian, Z., Miaomiao, W., Koon, Li. & Ke, F. Green construction project evaluation model based on C-OWA operator and vector entropy cosine. J. Civ. Eng. Manag. 34 (05), 39–45. https://doi.org/10.13579/j.cnki.2095-0985.2017.05.007 (2017).

Shu-Ping, W., Feng, W. & Jiu-Ying, D. A novel risk attitudinal ranking method for intuitionistic fuzzy values and application to MADM. Appl. Soft Comput. 2016 , 40 (2016).

Cai, W. & Shi, Y. The scientific significance and future development of topology. J. Harbin Inst. Technol. 07 , 1079–1086 (2006).

Wen, C. & Chunyan, Y. The basic theory and methodological system of topologists. Sci. Bull. 58 (13), 1190–1199 (2013).

Larsen-Freeman, D. National 18th annual conference of topology and 40th anniversary celebration of the founding of topology. J. Intell. Syst. 18 (02), 408 (2023).

Chaoyi, Y. A. N. G. et al. Evaluation and prediction of rock mass based on fuzzy RES-topology theory—a case study of Pulang copper mining area. Saf. Environ. Eng. 06 , 122–131. https://doi.org/10.13578/j.cnki.issn.1671-1556.20211511 (2022).

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Acknowledgements

This study was supported by the Science and Technology Research Project of Chongqing Municipal Education Commission (Grant No. KJQN202101337 & Grant no. KJQN202101322 & KJQN202201310 & KJQN202301312), the School-level Scientific Research Project of Chongqing University of Arts and Sciences (No. 2017YJ354), the Natural Science Foundation of Chongqing (No. cstc2019jcyj-msxmX0440), and the Major Breeding Project of Chongqing University of Arts and Sciences (No. P2018JG13). We also thank the students and colleagues from Southwest Petroleum University who took part in this survey research.

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Jian, H., Hao, H., Haidan, J. et al. Brownfield redevelopment evaluation based on structure-process-outcome theory and continuous ordered weighted averaging operator-topology method. Sci Rep 13 , 17530 (2023). https://doi.org/10.1038/s41598-023-44793-1

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Criteria for Preliminary Risk Assessment of Brownfield Site: An International Survey of Experts

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• Published: 04 August 2022
• Volume 70 , pages 681–696, ( 2022 )

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• Charf Mahammedi 1 ,
• Lamine Mahdjoubi 2 ,
• Colin Booth 2 ,
• Russell Bowman 3 &
• Talib E. Butt 4  

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Comprehensive risk assessment of brownfield sites requires a broad range of knowledge and multi-disciplinary expertise. Whilst the identification of criteria requirements for preliminary risk assessment has received some attention, there appears to be no studies that have specifically examined professional perspectives relating to these requirements. Yet, variations in professional practitioners’ assessments may have significant consequences for the assessment of risks, and how the criteria are imparted to stakeholders. This study aims to identify the criteria requirements for preliminary risk assessment, using the pollutant linkage model (Source–Pathway–Receptor), and explores cross-disciplinary professional perspectives related to these requirements. To this end, this study commenced with a systematic review to identify various criteria streams required for the preliminary risk assessment of brownfield sites. Thereafter, a questionnaire survey was design and shared with brownfield site professionals. Quantitative analysis of the survey responses ( n  = 76) reveals disciplines have markedly different priorities relating to the same hazard. For instance, geophysicists, geochemists, and hydrologists do not raise concerns regarding ground movement that can result from the removal of storage and tanks, whilst the same hazard was considered as having a high importance by other professions (such as geologists and geotechnical engineers). This example, amongst others revealed in the study, underpins potential issues and implications for various stakeholders compiling and/or using preliminary risk assessment criteria. This study clarifies both the key criteria requirements for the preliminary risk assessment of brownfield sites, as well as the importance of recognising how variation in professionals’ perceptions plays in the risk assessment process. Although, specialist knowledge is essential for brownfield site investigation, so is the maintaining a broad-based view of other experts coming from different backgrounds, as this renders holistic risk assessment insights.

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Introduction

Preliminary risk assessment has been more common in recent years as one of the critical stages for brownfield management, particularly when soil or groundwater contamination is involved (Butt et al. 2020 ; Mahammedi et al. 2020a ; Cushman et al. 2001 ). This phase of risk assessment aims to establish whether there are any potentially unacceptable risks with the site, whether any further information is likely to be needed to complete this stage or whether the site needs to be kept under review (Environment Agency 2016 ). The assessment process usually involves the analysis of substantial and wide ranging information to identify potential or existing constraints affecting the site or that could affect the site in the future (Martin and Toll 2006 ).

The main methodologies for performing risk assessments are provided by the US Environmental Protection Agency (U.S. EPA 2019 , 2014 , 1989 , 2001 , 1997 ), the UK Environment Agency (EA) (Environment Agency 2008 ; DEFRA; Environmental Agency 2004 ; Environment Agency 2009 , 2015 , 2017 ), and the Canadian Council of Ministers for the Environment (CCME) (Health Canada 2010 ). According to Cushman et al. ( 2001 ), there are three main types of risk assessment used for addressing brownfield related issues: a human health risk assessment, an environmental risk assessment and building structures. A human health risk assessment evaluates the risks associated with human exposures to contamination. An environmental risk assessment evaluates the risks associated with flora and (or) fauna exposures to contamination. Building structures risk assessment, which is less prominent than the first two, but no less important, assesses the risks posed to building structures (i.e. permeation and (or) degradation of underground utilities, sewers, building foundations, etc.) due to contact with contamination.

A systematic review and analysis of the available risk assessment literature for brownfield and contaminated sites was conducted by Mahammedi et al. ( 2020a ), who identified 31 tools and holistically classified them in terms of risk assessment stages, and types of harms, hazards, pathways and receptors. The results show that risk analysis tools for contaminated sites are detailed, complex, time consuming, effort-intensive and costly for preliminary assessment. It establishes the escalating need of preliminary risk assessment tools which are appropriately detailed, nothing more, nothing less. Another review was published by the European Environment Agency (EEA, 2004 ), where a number of documented international methodologies are listed and analysed. The approaches reviewed are mostly used to rank potential contaminated sites based on existing data in order to develop priority action plans related to detailed site survey and remediation. The reviewed methodologies follow a qualitative method to assess the risks raised by potential contaminated sites. They define the three components of a risk assessment model (i.e. source, pathway and receptor) in terms of scores for assessing related risks, instead of absolute estimates of health/environmental impacts (Zabeo et al. 2011 ; Pizzol et al. 2011 ). Prioritisation methodologies, including the Multi–Criteria Decision-Making (MCDM) method, have been proposed in a range of brownfield regeneration process (Linkov et al. 2020 ; Cinelli et al. 2021 ), including the application of AHP and Fuzzy AHP for forest conservation (Wolfslehner et al. 2005 ; Laxmi et al. 2012 ), landfill site selection (Wang et al. 2009 ; Donevska et al. 2012 ), site selection (Chen 2006 ; Vahidnia et al. 2009 ), remediation techniques (Linkov et al. 2004 ; Promentilla et al. 2008 ), and VAHP for potential hazards associated with brownfield sites ((Mahammedi et al. 2021 ).

Inadequate site assessment may expose investigation personnel, and the general public, to unnecessary and unacceptable risks. These can even lead to more extensive or intractable contamination problems than those that previously existed on a site (Harris and Herbert 1994 ; Mahammedi et al. 2020b ). Land acquisition without appropriate investigation can result in the developer incurring financial and legal liabilities. For instance, Shepherd ( 2020 ) reported a case study where a buyers bought a houses in Bradford, UK without preliminary risk assessment. After acquisition, the houses were found worthless because the estate backs onto what used to be a landfill site. Despite it being inactive for over four decades, the council says it still releases toxic methane gas. This meant the scheme design adversely impacted the project profit. In another example, cases of ill health were recorded affecting some residents in the former mining area in Midlothian, Scotland. Investigations revealed residents were suffering from exposure to carbon dioxide (CO 2 ) released from historical coal mines beneath their homes. Demolition of 64 homes was the only option to prevent the possibility of further leaks of carbon dioxide into these homes over the longer term (BBC 2014 ). Both incidents serve as a stark reminder of the potential jeopardies involved with reusing of brownfield sites.

Successful investigation of brownfield sites typically requires multi-disciplinary expertise and a multi-staged approach, as well as multi-agency regulation to analyse the immense volume of information needed to make a complete risk assessment of a site (Nathanail 2009 , 2013 ; Marsili 2016 ). Risk assessment is highly complex and requires information from many disciplines, taking into consideration the range of contexts in which decision have to be made, including complying with industry standards, relevant legislative frameworks, health and safety issues, accounting for total operating costs and benefits, and addressing issues of environmental impacts, sustainability, protection of other resources, and importantly the prevention of further and/or future contamination (Bello-Dambatta 2010 ). One of the key challenges is an enhanced awareness of the varying priorities and competencies that other professionals working on brownfield sites have and how these might be reconciled for more effective risk assessment. Amongst the difficulties facing brownfield site assessors is the quantity of potential risks on the development of brownfield sites that are often far from what assessors can expect to identify (Kovalick and Montgomery 2017 ). This may increase misunderstanding and communication issues between various stakeholders.

The risk assessment process for sites covers a range of knowledge branches such as the environment, geology, hydrology, geotechnics, chemistry, and alike. Consequently, the process requires engagement from and with a wide range of experts from different backgrounds. According to Nathanail ( 2009 ), engineering geology has an essential role to play in ensuring that risk assessments are applied, appraised, and implemented in ground investigations. For example, the fate and transport of contaminants is a function of engineering geological parameters (solubility, volatilisation, etc.) and the properties of the ground they are in (clay content, pH, organic matter content, etc.). In addition, Jefferis ( 2010 ) indicated that geotechnical engineers should be encouraged to pro-actively minimise the risk of future contaminated land. They should be prepared to use their accumulated experience of the behaviour of chemicals in the ground and groundwater environments to raise concerns about the widespread use or use without sufficient protection of chemicals that are manifestly dangerous to the environment.

There is a need for more inclusive criteria coming from the perspective of various professional practitioners in view of their different backgrounds; thereby, enabling a more holistic and complete identification of hazards (with their diverse implications) for a given brownfield site. Having prior knowledge about the typical information that should be gathered to identify the three components of the pollutant linkage model (Source–Pathway–Receptor) reduces the risk of encountering unforeseen hazards and decreases the unnecessary cost of the site investigation. The source of hazards in brownfield sites are investigated by Vik and Bardos ( 2003 ), Environment Agency ( 2004 , 2008 ), Harrison ( 2015 ), and Mahammedi ( 2021 ) it was concluded that the main source of hazards is the chemical and biological contamination arising from past industrial use, which may present a major threat to different human health and built environment. Furthermore, Leach and Goodger ( 1991 ), Charles et al. ( 2002 ), Charles ( 2005 ), Wilson et al. ( 2007 ) investigate physical hazards including ground movement and obstructions (i.e. buried foundations, underground services, old tanks etc.). Pathway identifies how hazards were released from the source into the environment (Butt et al. 2016 ). The pre-exposure is mainly subjected to investigate the impact of site conditions including site geology, hydrology and topography on the fate and transport of contaminants.

From the perspective of brownfield sites, preliminary risk assessment involves collecting enough reliable and accurate criteria to identify the three component of pollutant linkage model. For the three components, no evidence has been found of particular studies that can help to identify the required criteria to establish the pollutant linkage model more holistically and categorically. This study is not about the preliminary risk assessment itself, as such which is hazard identification and hazard assessment (DEFRA and Environment Agency 2004 ; AECOM Infrastructure and Environment UK Ltd 2017 ). The study is rather about identifying and characterising/categorising the types of data and information which are fundamentally required to form the basis of preliminary risk assessment. The study signifies such data and information without which preliminary risk assessment cannot be conducted in the first place. The aim of this study is to identify the risk assessment criteria of brownfield site at early stage of risk assessment based on pollutant linkage model.

Research Design and Methodology

This study adopts a quantitative research strategy; whereby, after a comprehensive review of brownfield site literature, a questionnaire survey was used for the collection of empirical data. An overview of the process adopted for this study is detailed below (Fig. 1 ), which shows a four-stage process. Stage one identifies the criteria for preliminary risk assessment based on existing literature. Stage two uses a questionnaire administered to disciplinary experts to validate the literature findings. Finally, stage three comprises statistical analysis of the survey data using the SPSS 26.0 statistical package to enable conclusions to be drawn out.

Overall research design

Identification of Criteria for Preliminary Risk Assessment of Brownfield Sites

In order to identify the key criteria for preliminary risk assessment, it was decided to screen the literature. This review was conducted on academic and professional databases, plus grey literature. The academic database included: Scopus, American Society of Civil Engineers (ASCE), Institution of Civil Engineers (ICE) virtual library and other relevant literature including government guidance and technical reports. The search words were a combination of “Preliminary criteria”, “Hazard assessment”, “Hazard identification”, “Contaminated sites”, “Brownfield sites”, “Site investigation”, “Site appraisal” and “Site report”. They were selected for their relevance to preliminary risk assessment of brownfield sites and returned relevant literature from the majority of main journal and conference publications.

After removing duplicates subsequent exclusion rounds were completed through reading of the titles, then the abstract and finally the full articles. The following suitability criteria were adopted: (i) relevant literature that does concern preliminary assessment and brownfield sites, (ii) adequate quality. The review findings are presented in Table 1 .

Survey Design, Sample Recruitment and Data Collection

A questionnaire was developed using the online survey tool Qualtrics. To determine the convenient target groups for the online survey, the questionnaire adopted the purposeful sampling method. Also called judgement sampling, this technique is a non-random procedure, in which the researcher relies on his or her judgement when selecting members of the subjects to participate in the study (Saunders et al. 2019 ). Purposive sampling is employed because the investigator is looking for strong information in a certain area of expertise and wants to learn more about the subject. Therefore, the survey is limited to companies with brownfield management experience, working in the UK and North America. These were selected from the main brownfield groups on LinkedIn. These groups included Brownfield Briefing (739 members), Property and Real Estate Development, Town Planning, Design, Funding and Construction Solution (5825 members), CABERNET—Europe’s brownfield regeneration network (member 548), UK Brownfield Investigation Assessment and Remediation (812 members), Construction Industry Research and Information Association (CIRIA) (3000 members), Florida Land Development News (343 members). The survey was divided into two main sections. The first section requested demographic information about the participant’s background and years of experience. The second section adopted a five-point Likert scale (Table 2 ) to rate the criteria with a five-point rating scale (1 = not important, 2 = less important, 3 = neutral, 4 = important, and 5 = very important). It comprises 49 questions across 7 sub-sections, covering: (i) obstruction hazards (nine questions); (ii) ground movement (nine questions); (iii) chemical contaminants (nine questions); (iv) biological hazards (nine questions); (v) biodegradable effects hazards (nine questions); (vi) contaminant movement (four questions); and (vii) receptor (two questions). In this study, Likert items are considered an interval level data with distance between the points. Therefore, the data analysis decision for Likert scale items can use the mean to measure the central tendency. It important to mention that three academic professionals piloted the online survey before it was accepted as a final survey, focusing on question construction, this ensured that the questionnaire was meaningful and easy to follow.

Participants are asked to read and understand the participant consent and participant information sheet, and then if they are interested, they could proceed via an attached link to the survey. The survey was left open for 4 months to collect the highest number of responses. Moreover, ethics and moral standards are integral to research studies. Therefore, all participants were informed their involvement was voluntary and their decision to return their questionnaire would be deemed as their consent to take part in the survey. As their responses would be anonymous, participants were invited to create their own unique identification code in case they wished to withdraw up to 2 weeks after the completed survey had been returned. The study was conducted in accordance with the ethics regulations at the University of the West of England (UWE), Bristol.

Data Analysis

The data collected from the survey was analysed using various statistical analysis methods, which are described in this section.

Reliability Test–Cronbach’s Alpha

Cronbach’s alpha test remains one of the most popular methods for assessing the reliability, or internal consistency, of a set of scale or test items. It is computed by correlating the score for each scale item with the total score for each observation and then comparing that to the variance for all individual item scores. Data is said to have high reliability if it produces similar results under consistent conditions. The Cronbach’s alpha coefficient value ranges from 0 to 1, and the higher the value, the more reliable is the adopted scale of measurement. Tavakol and Dennick ( 2011 ) argued that, if the alpha value is above 0.70, it indicates an excellent internal consistency within the data. Using SPSS, the Cronbach’s alpha coefficient value could be calculated as following (Darko 2019 )

Where: N = the number of items. \(\overline c\)  = average covariance between item–pairs. \(\overline v\)  = average variance

In this study, Cronbach’s alpha coefficient test was used to assess the reliabilities of the five-point rating scales used to capture the survey responses.

The mean score of the importance of the criteria is calculated using the following formula:

Where n : the total number of participants; α ij : the importance of the criteria i rated by the participant j ; and B i : the mean score of the importance of the criteria i . The SPSS statistical software was used to calculate the mean score for the criteria, and for ranking the criteria. For research rigour, only criteria with mean scores higher than 3.40 was important. This approach was adopted from Pimentel ( 2010 ) and does not only determine the necessary criteria to identify pollutant linkage model, but also helps to reduce a large number of criteria to a reasonable number to allow reliable and effective risk assessment. The findings of this analysis are presented in Table 4 .

Data Normality Test

The Shapiro–Wilk test examines if a variable is normally distributed in a population. The null hypothesis of the Shapiro–Wilk test is that the data were normally distributed. The test rejects the hypothesis of normality when the p value is less than or equal to 0.05, and conclusion that the data are not normally distributed must be made (Royston 1992 ).

Intergroup Comparison to Determine Intergroup Statistical Differences

Kruskal–Wallis H test determined whether there were any statically significant differences in respondents’ perception based on their professional roles on the rating of the importance of criteria on identifying the pollutant linkage component. While the p value (Asymp. Sig) < 0.05 would reveal a noteworthy difference in the perception of the respondents.

Intergroups Pair-wise Comparison

Mann–Whitney U test is used in this study to perform multiple pair-wise non-parametric comparisons if the Kruskal–Wallis H test shows a significant difference among participants. This test is used to compare differences between two independent groups when the dependent variable is either ordinal or continuous, but not normally distributed (McKnight and Najab 2010 ).

Level of Agreement Amongst Participants

In order to check agreements among the participants regarding the ranking of the site criteria to establish pollutant linkage model and the potential hazards associated with brownfield sites, Kendall’s coefficient of concordance (also known as Kendall’s W) test was conducted. Kendall’s W test is a non-parametric statistic. It is a normalisation of the statistic of the Friedman test and can be used for assessing agreement among participants (Rasli 2006 ). Kendall’s W tests the null hypothesis that “no agreement exists among the rankings given by the participants in a particular group”. It ranges from 0 (no agreement) to 1 (complete agreement) (Lewis and Johnson 1971 ).

Where: \({\sum} {R_i^2}\) is the sum of the ranks for the individual ranked N factors object; k is the total number of participants or rankings; and \(k{\sum} {T_j}\) is the sum of values of T j over all k sets of ranks.

Findings from the analysis of the survey responses are presented and discussed beneath. This section reveals the profiles of the participants (section Demographic Profiles) before analysing and interrogating the data and information returned (section Analysis Findings).

Demographic Profiles

Following screening of the returned questionnaires and scrutiny for missing data, the final response rate of thirty-eight percent was yielded from 76 complete surveys. The demographic profiles of the survey participants are presented (Table 3 ). This shows geotechnical and geo-environmental engineers compose most of the participant’s professions (38%; n  = 29), with hydrologists geochemists, geophysicists and geologists comprising the other roles. Sixty-one percent ( n  = 46) of those taking part in the survey each have more than 6 years’ experience of working as brownfield site professionals.

Analysis Findings

Before analysing the collected data, the reliability of the data and the normality were tested using the Cronbach’s alpha coefficient test and the Shapiro–Wilk test, accordingly. The calculated Cronbach’s alpha value for the 49 questions was 0.79. This is higher than the threshold of 0.70, which indicates that the measure of the five-point scale and thus the data collected is very reliable for further analysis. Moreover, in this study, all the p value calculated by the Shapiro–Wilk test was <0.05, which confirmed that the collected data were not normally distributed. This is expected because for small sample sizes, the sampling distribution of the mean is often non-normal distributed (Royston 1992 ).

Findings from the analysis of the survey responses are presented and discussed beneath. The results presented in Table 4 reveal that the respondents do not differ based on their roles, only as none of the criteria has its Kruskal–Wallis H test coefficient <0.05, except the ground movement where the results indicated that there is a statistical difference in the perceptions of the six professionals regarding the importance of storage of material and old tank ( X 2  = 21.478; p value < 0.05; n  = 76) and invasive species ( X 2  = 22.182; p value < 0.05 n  = 76) criteria to determine the ground movement in brownfield sites. Therefore, Mann–Whitney U test was conducted to find the cause of the significant differences.

In addition, Kendall’s W test was performed to calculate the coefficient of concordance. The results of the analysis show a significant degree of agreement exists among all of the participants regarding the ranking of potential hazards associated with brownfield sites.

As mentioned in section 3.5, Mann–Whitney U test was used was conducted to find the cause of the significant differences. Starting with the storage of materials and old tanks, the results presented in Table 5 showed that the reason for the statistically significant differences is due to the mean rank of geochemist engineering ( \(\overline {X_1} \,=\, 8.75\) ; \(\overline {X_2} \,=\, 8.25\) ; \(\overline {X_3} \,=\, 7.75\) ) were lower than geo-environmental engineering ( \(\overline {X_1} \,=\, 16.75\) ), geologist \(\left( {\overline {X_2} \,=\, 14.88} \right)\) and geotechnical engineering \(\left( {\overline {X_3} \,=\, 15.27} \right)\) respectively. The test indicated that this difference was statistically significant, ( U 1  = 32.500; P 1  = 0.002), ( U 2  = 27.500; P 2  = 0.012), and ( U 3  = 22.500; P 3  = 0.004) successively. In addition, Mann–Whitney U test shows that there was significant difference between geophysicists ( \(\overline {X_4} \,=\, 9.75\) ; \(\overline {X_5} \,=\, 9.58\) ; \(\overline {X_6} \,=\, 8.92\) ) on the one hand and geo-environmental engineering ( \(\overline {X_4} \,=\, 18.06\) ), geologist ( \(\overline {X_5} \,=\, 16.15\) ) and geotechnical engineering ( \(\overline {X_6}\)  = 16.77) on the other hand. The test indicated that this difference was statistically significant, ( U 4  = 39.000; P 4  = 0.001), ( U 5  = 37.000; P 5  = 0.017), and ( U 6  = 29.000; P 6  = 0.004) successively. Mann–Whitney U test shows also that was significant difference between hydrologists ( \(\overline {X_7} \,=\, 10.96\) ; \(\overline {X_8} \,=\, 9.67\) ) and geo-environmental engineering ( \(\overline {X_7} \,=\, 17.16\) ) and geotechnical engineering ( \(\overline {X_8} \,=\, 16.08\) ). The test marked that this difference was statistically significant, ( U 7  = 53.500; P 7  = 0.017) and ( U 8  = 38.000; P 8  = 0.019) successively.

Regarding invasive species criteria, Mann–Whitney U test was applied to find the cause of the significant differences, the results are presented in Table 6 . The results show that the reason for the statistically significant differences is due to the mean rank of geophysicists ( \(\overline {X_1} \,=\, 10.42\) , \(\overline {X_2} \,=\, 8.71\) ; \(\overline {X_3} \,=\, 8.75\) ) were lower than geo-environmental engineering ( \(\overline {X_1} \,=\, 17.56\) ) geotechnical engineering, ( \(\overline {X_2} \,=\, 16.96\) ) and geologist ( \(\overline {X_3} \,=\, 16.92\) ) respectively. The test indicated that this difference was statistically significant, ( U 1  = 47.000; P 1  = 0.018), ( U 2  = 26.500, P 2  = 0.003) and ( U 3  = 27.000; P 3  = 0.004) successively. Furthermore, Mann–Whitney U test shows that there was significant difference between hydrologist ( \(\overline {X_4} \,=\, 10.33\) ; \(\overline {X_5} \,=\, 8.33\) and \(\overline {X_6} \,=\, 8.50\) ) and geo-environmental engineering ( \(\overline {X_4} \,=\, 17.63\) ), geotechnical engineering ( \(\overline {X_6}\)  = 17.31) and geologist ( \(\overline {X_5} \,=\, 17.15\) ). The test indicated that this difference was statistically significant, ( U 4  = 46.000; P 4  = 0.015), ( U 5  = 22.000; P 5  = 0.001), and ( U 6  = 24.000, P 6  = 0.002) successively. Mann–Whitney U test shows also that was significant difference between geochemist ( \(\overline {X_7} \,=\, 8.50\) ; \(\overline {X_8} \,=\, 8.60\) ) on the one hand and geotechnical engineering ( \(\overline {X_7} \,=\, 14.69\) ) and geologist ( \(\overline {X_8} \,=\, 14.62\) ) on the other hand. The test marked that this difference was statistically significant, ( U 7  = 30.000; P 7  = 0.013) and ( U 8  = 31.000; P 8  = 0.025) successively.

This study also analysed the participants’ agreement regarding the ranking of potential hazards associated with brownfield sites. Kendall’s W test result of W with the small associated level of significance of 0.001 ( n  = 76) implied that there was a significant degree of agreement between the respondents regarding the necessary criteria to identify hazards in brownfield sites. This signifies that there is a strong agreement among the six professionals of participants on the importance rating of criteria to determine the pollutant linkage components. The outcome of this analysis is presented in Table 4 .

Based on the design of the source–pathway–receptor model, this section discusses the findings and then considers the potential issues and implications.

Source—Obstruction Hazards

By previous use, brownfield sites contain buildings, ancillary structures, and underground services. These pose potential barriers to redevelopment, which could be of great consequence if not anticipated and planned when discovered during construction (Barry 1991 ). The results show a significant degree of agreement between the professionals regarding the necessary criteria to identify obstruction hazards in brownfield sites. Six professional groups agreed on the importance rating of criteria to determine the potential obstructions.

In general, buildings and other structures (mean = 4.88; SD = 0.325; n  = 76) were perceived to be the most important criteria to identify obstruction in brownfield sites. This is expected result as it is common to find obstruction in brownfield sites. Moreover, underground service criteria is essential because damage to underground services can cause fatal or severe injury. For example, underground electrical cables carry considerable hazardous because they often look like pipes and it is hard to know if they are live just by looking at them. This criteria was rated extremely important by mean = 4.87 (SD = 0.340; n  = 76). As expected, storage of materials and old tanks was rated high by mean = 4.84 (SD = 0.367; n  = 76) amongst the criteria to identify obstructions in brownfield sites, mainly because they present a potential obstruction to redevelopment which, if not foreseen and planned for, can have a major significance when discovered during construction. History of the site rated with mean = 4.74 (SD = 4.74; n  = 76), which provides evidence that this criteria is emphasised by the experts, as an extremely important indication of potential obstruction. Participants perceive “Previous mining activities” (mean = 4.72; SD = 0.532; n  = 76) criteria as vital to identify obstruction (i.e. underground pipe runs, tanks, etc.). This finding is consistent with the previous study by Leach and Goodger ( 1991 ) concerning the physical hazards in derelict sites.

Source—Ground Movement

Brownfield sites have the potential for ground movement, where settlement is the most common form but, in certain situations, the ground may heave (Charles 2005 ). The findings show that made ground was ranked first by professionals (mean = 4.63; SD = 0.608; n  = 76). This result is in great agreement with studies (Watts and Charles 1997 ; Charles and Skinner 2004 ) showed a significant issue to the foundations of buildings due to the compressibility of the ground. Criteria related to previous mining activities ranked second by mean = 4.24 (SD = 0.781; n  = 76). It is understandable because such an industry may leave a wide amount of slags that cause expansion on wetting (Charles et al. 2002 ). The third issue ranked by participants was criteria related to the history of the site (mean = 4.08; SD = 0.648; n  = 76). These findings were highlighted by a study conducted by Sivapullaiah et al. ( 2009 ) who demonstrated that the swelling of soil in the presence of waste material such as sulfuric acid is highly likely due to the leaching of fixed potassium ions from between the interlayers. Storage of materials and old tanks criteria ranked fourth by mean = 3.83 (SD = 0.915; n  = 76), although geophysicist, geochemists, and hydrologist do not rank this criteria important to identify ground movement, it was ranked extremely important by other professionals as it raises concerns about the ground instability related to removing tanks and underground storages as highlighted by previous study by Barry ( 1991 ).

Although the invasive species (mean = 3.38; SD = 0.821; n  = 76) was <3.40, it was marginally important as a number of professionals including geo-environmental engineers, geotechnical engineers, and geologists considered invasive species as important criteria to identify the ground movement in brownfield sites, where they are known to cause significant landslides and soil loss in areas that are colonised by Himalayan balsam (Greenwood and Kuhn 2014 ). This hazard was underestimated by geophysicists, hydrologists, and geochemists the importance of this criteria to identify ground movement.

Source—Chemical Hazards

Chemicals are one of the most important hazards arising from industrial use, which may present a major threat to humans. History of the site criteria provides a good indication of potential sources and types of chemicals likely to be found on site. As expected, participants ranked first this criteria as extremely important by mean = 4.75 (SD = 0.465; n  = 76). The second, as the participants ranked was made ground by mean = 4.63 (SD = 0.538; n  = 76). This expected as made ground may cause pollution, where liquid waste (Leachate) leaking is a major issue related to ground pollution (Sarsby and Felton 2006 ). Surrounding area criteria was ranked third with a mean = 4.52 (SD = 0.608; n  = 76). This is expected, mainly because, in areas where the surrounding sites are known by historical industrial activities, it can be considered as a source of contamination, because the behaviour of the site containing contamination is the long-term migration of the contaminants itself to potential receptors (Gurunadha Rao and Gupta 2000 ). The criteria related to the presence of radon ranked fourth by participants with a mean = 4.43 (SD = 0.736; n  = 76) as it is the most common source of exposure to radiation, easily exceeding exposure from nuclear power stations or hospital scans and X-rays (EPA 2019 ). Previous mining activities criteria was ranked fifth by mean = 4.39. This can be explained as such as criteria is a good indicator to identify a range of chemical contaminants in particular steel-making processes (Charles 2005 ). Storage of materials and old tanks was ranked sixth by mean = 4.34. This finding is consistent with the previous study by Motta et al. ( 2017 ), and Beiras ( 2018 ) concerning the fuel storage and distribution at industry manufacture as one of the main causes of soil and groundwater contamination, due to leakage from piping, from underground storage tanks. The criteria related to invasive species ranked seventh by mean = 3.74 (SD = 0.943; n  = 76). According to Elliott ( 2003 ), this criteria can help investigators to identify chemical hazards that may cause serious health issues including poisoning, scars, and blindness if the sap gets into the eyes. The results (Table 4 ) indicated that there is not statistically different in the perceptions of the six professionals, as none of the criteria has its Kruskal–Wallis H test coefficient <0.05.

Source—Biological Contaminants

There are a number of biological hazards that may be exist on a brownfield site and any of these could lead to disease if precautions are not taken to reduce the risks. Some of these diseases can be serious or fatal (Kovacs and Szemmelveisz 2017 ). It is not surprising that the history of the site ranked first by mean = 4.55 (SD = 0.501; n  = 76) because industries and activities such as sewage, hospital waste, landfills, canals, laboratory waste and disease/burial pits are the main sources for bacteria, fungi, parasites and viruses. Made ground ranked second by mean = 4.49 (SD = 0.663; n  = 76). This can be explained as wastes contaminated with biological materials could lead to disease if precautions are not taken to reduce the risks. Thirdly, surrounding areas by mean = 4.37 (SD = 0.538; n  = 76). This criteria is extremely useful because surrounding areas are known by industrial activities, it can be considered as a source of biological contamination, which may migrate to potential receptors. Although the results confirmed the similarity in the perception of professionals about the most appropriate criteria to identify the biological contaminants in brownfield sites, invasive species criteria was underestimated by most of the participants and this contradicts a study conducted by (Elliott 2003 ) which considered invasive species as biological pollution were, the terms biological pollutants have been used by (Boudouresque and Verlaque 2002 ) to discuss the problems caused by such invasive species. Therefore, there is a need to enhance the knowledge of professionals concerning the biological hazards of invasive species.

Source—Biodegradable Hazards

Participants ranked made ground first by mean = 4.53 (SD = 0.663; n  = 76) to identify biodegradable effects in brownfield sites. This criteria provides a good indicator about the hazards related to biodegradable materials during the long process of decomposition, where biological reactions in landfills can convert organic compounds to several different gases, called biogas Talaiekhozani et al. ( 2018 ). In addition, the history of the site was rated also extremely important because it generally provides a good indication of former waste disposal sites that contain biodegradable materials. These criteria ranked second by mean = 4.42 (SD = 0.634; n  = 76). Surrounding areas criteria ranked third by mean = 3.97 (SD = 0.588; n  = 76). This finding was highlighted by many studies (Kanmani and Gandhimathi 2013 ; Locatelli et al. 2019 ), where the accumulation of landfill gas may attribute to lateral migration of landfill gas from old waste fill sites to adjacent sites. Landfills gas can migrate significant distances because it is affected particularly by ground permeability. The results presented in Table 4 confirmed that the individual groups did not differ significantly, as none of the criteria has its Kruskal–Wallis H test coefficient <0.05.

Pathway—Contaminants Movement

Pathway identifies how hazards were released from the source into the environment (Butt et al. 2016 ). It is mainly subjected to investigate the impact of site conditions on the fate and transport of contaminants (Wu et al. 2019 ). Criteria related to site geology (i.e. soil permeability and thickness) ranked first by mean = 4.64 (SD = 0.559; n  = 76). This can be explained as soil permeability parameter is one of the most important factors within the pathway process where contaminant movement is more likely in a highly permeable layer than an impermeable layer. In addition, the soil thickness parameter also plays an essential role when assessing contaminants pathway movement, as the thicker the layer the longer takes the contaminants to move through it (British Standard 2015 ). Site hydrology (i.e. presence of surface water and flood zones) ranked second by mean = 4.53 (SD = 0.589; n  = 76), this criteria plays also a critical role when assessing possible pathways because it influences the movement of potential contaminants and the potential exposure pathways to human health and environmental receptors. While site topography (i.e. flat site and steep site) ranked third by mean = 3.74 (SD = 0.737; n  = 76). It is understandable why this criteria ranked important by participants because it plays an important role in identifying the direction of the contaminant pathway. Site hydrogeology (i.e. presence of groundwater) ranked fourth by mean = 3.67 (SD = 0.90; n  = 76). This criteria provides a useful reminder to assessors that the presence of groundwater and/or surface water assists the movement of contaminants, therefore increasing the risk of contaminants migration.

It can be seen that all criteria does not show a significant difference between job categories. This signifies that there is a strong agreement among the six professionals of participants on the importance rating of criteria to determine the potential obstructions.

Receptors—Future Land Users and Building Materials

Risks posed to human health is usually the dominant issue in the redevelopment of brownfield sites (Skinner et al. 2005 ). It is expected that future end-use criteria ranked extremely important to identify hazards posed to human health by mean = 4.86 (SD = 0.896; n  = 76). Otherwise, criteria related building materials considered important by mean = 3.47 (SD = 0.768; n  = 76) to assess the risks posed to buildings because at brownfield sites, building materials are often subjected to aggressive environments that cause them to physical or chemical changes. The results show that there is a strong agreement among the six professionals of participants on the importance of criteria related to the future user and building materials to determine the potential targets.

Potential Issues and Implications

The starting point of the brownfield risk assessment process is hazard identification, which is a complex relationship of sources, pathways and receptors (Environment Agency 2008 ). This process is often quite time consuming as it usually involves gathering a vast number of criteria to fully assess a potentially hazards. Therefore, there is a need for toolkit/mechanism of appropriate criteria which assist specifically in connection to contaminated sites for clearing and redevelopment via land reclamation. Such a toolkit is to save time, effort and other resources. essential that the correct criteria required for the development of such a site is collected and used in the most cost-effective manner.

This paper produces a set of criteria to assist in identifying the possibility of existence of hazards in a given brownfield/contaminated site. This process is not to capture the degree of ‘hazardousness’/concertation of a hazard as an whether it is below or above an acceptable safe level of concertation. The idea is to save risk assessors and other associated stakeholders from investing their time, effort, cost and other resources in the hunt of those hazards which are not possible to exist in the first place. For instance, the history (which one of the criteria) of a brownfield site is oil abstraction or petrol station, then the risk assessor focus should be to establish the existence of hydrocarbons in the soil regardless of the degree of concentration of hydrocarbons, be it lower or higher than the safety levels for a given scenario. Furthermore, another criterion is regarding the sensitivity of the potential receptor. If, continuing from the same example, a school is to be built or playground for children then the process would indicate the direction and the depth of the follow-on detailed risk assessment, as appropriate. On the other, if a car park is constructed then that would accordingly reduce the depth of the follow-on risk assessment exercise. In summary, the criteria identified in this study time and cost effectively set the scene for follow-on measures in terms of amount, depth and direction.

This study reveals challenges facing the investigators of brownfield sites to identify the risks and hazards associated with brownfield site development. The risk assessment process is sometimes failed by assessors where many of application were refused by local authorities due to not comprehensively and successfully identify potential hazards. Another challenge in the assessment of brownfield sites is commonly required expertise and knowledge from a number of disciplines, ranging from geotechnical engineers to geochemical scientist to provide an independent professional report about the risks, particularly to human health and the built environment, by identifying actual or potential hazards of the site (Nathanail and Bardos 2005 ; Nathanail et al. 2011 ). According to the Environment Agency ( 2008 ), the lack of criteria increases uncertainties in identifying and assessing hazards, which leads to poor communication between stakeholders, possibly leading to different suitably qualified stakeholders reaching to different conclusions even when presented with the same criteria. However, excessive detail should be avoided, and the level of detail should be no more than is needed for robust decisions to be taken.

The findings of this study clarify both the key criteria requirements for the preliminary risk assessment of brownfield sites, as well as the importance of recognising how variation in professionals’ perceptions plays into the risk assessment process. Even though specialist knowledge is fundamental to the brownfield investigation, maintaining a wide perspective of experts coming from different backgrounds is critical, as this makes the risk assessment more comprehensive and complete. This encourages the reuse of brownfield sites, especially in countries that have adopted a policy of preservation of green fields and enhancing sustainable redevelopment.

The identified generic criteria are for preliminary risk assessment stage to be a cost effective. However, when the outcome of the preliminary risk assessment suggests carrying out a detailed risk assessment, at that point these generic criteria can be investigated in lot more site-specific context for a given brownfield site. Figure 2 shows preliminary risk assessment (PRA) model 13 criteria based. The criteria for the initial risk assessment will depend on the context and objectives of the risk assessment, as well as on the general characteristics of the site. The criteria provide an indication of the general type of information that may be required for an initial risk assessment. The evaluator will need to identify the specific information required in any situation and focus the information gathering on meeting those information needs.

Preliminary risk assessment of brownfield site 13 criteria based

Conclusions and Future Research

This study aimed to determine the criteria necessary for the initial risk assessment of brownfield site based on the pollutant linkage model (Source–Pathway–Receptor) with focus on the level of agreement and disagreement between expert groups in their perception of the criteria requirements. A total of thirteen criteria were identified through a systematic review and presented to expert groups to gauge their level of importance in relation to preliminary assessment of brownfield sites. Participants were required to identify the appropriate criteria to identify the pollutant linkage components.

The results of statistical analyses of seventy-six expert responses indicate that the top criteria to identify the source of hazards are history of the site, made ground, invasive species, previous mining, storage of materials and old tanks, presence of radon, underground services and buildings and other structures. Furthermore, site geology, site hydrology, site hydrogeology and site topography were rated as the top criteria to identify the pathway movement of the contaminants. While future site use scenario criteria is critical to identify the critical receptor of the population most likely to be exposed and/or susceptible to the presence of soil contamination.

The study renders the preliminary risk assessment exercise to be not only more holistic and integrated but also to reduce uncertainty in risk assessment by ensuring that all eventualities along with their respective significance have been encapsulated at the initial stage of risk assessment. Another important element of the study brought out is that the same hazard and associated risk can be of varying significance to different professionals. So much so that a crucial hazard in the eyes of one practitioner may not be a hazard at all in the eyes of another practitioner, merely due to the difference in their backgrounds. This variation in views and interests of different professionals can help the risk assessor to develop the pollutant linkage model of the brownfield site more categorically and systemically, encapsulating all possible hazards, pathways and receptors. A diversity of professional engagements would enhance the capability of the risk assessor to signify and appropriately prioritise hazards in the preliminary risk assessment with greater confidence.

Finally, this study advocates the need for more inclusive criteria to come from the perspective of various professional practitioners in view of their different backgrounds; thereby, enabling more holistic and complete identification of hazards (with their diverse implications) for a given brownfield site.

Based on the findings revealed in this study the following recommendations are proposed:

Future research could also determine the total population of professionals in the brownfield redevelopment sector and employ a larger sample to comprehensively analyse the differences between professionals’ perceptions.

Lastly, future research could attempt validate the findings of this study through real case studies of risk assessment to quantify and show the real benefits to policy makers, industry stakeholders, which could make preliminary risk assessment of brownfield sites more attractive for them.

The idea of carrying out a PRA prior to detailed risk assessment (which is more costly and time consuming and a liber intensive) can be enhanced by developing a full-on model and validated via applying to wide range of brownfield site.

AECOM Infrastructure; Environnent UK Ltd (2017). Land Contamination and Archaeology: Good Practice Guidance. Historic England.

Barry D (1991) Hazards in land recycling. In: George F (ed). Recycling derelict land. Thomas Telford, London, p 28–63. https://doi.org/10.1680/rdl.13186.0003

BBC (2014) Gorebridge homes to be demolished after carbon dioxide gas leak. https://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-27905611 Accessed 21 Dec 2020

Beiras R (2018) Hydrocarbons and Oil Spills. In: pp. 89–106. https://doi.org/10.1016/B978-0-12-813736-9.00007-6

Bello-Dambatta A (2010) The Development of a Web-based Decision Support System for the Sustainable Management of Contaminated Land. University of Exeter. http://hdl.handle.net/10036/119265

Boudouresque CF, Verlaque M (2002) Biological pollution in the Mediterranean Sea: invasive versus introduced macrophytes. Mar Pollut Bul 44(1):32–38. https://www.sciencedirect.com/science/article/pii/S0025326X01001503 https://doi.org/10.1016/S0025-326X(01)00150-3 Accessed 13 May 2019

British Standard (2015) British Standard 5930, Code of practice for ground investigations. British Standards Institution, London.

Butt TE, Akram H, Mahammedi C, House C (2020) Conceptual site model: an intermediary between baseline study and risk assessment. WIT Trans Eng Sci 129:101–108

Article   Google Scholar  

Butt TE, Javadi AA, Nunns MA, Beal CD(2016) Development of a conceptual framework of holistic risk assessment—landfill as a particular type of contaminated land Sci Total Environ 569–570:815–829. https://doi.org/10.1016/j.scitotenv.2016.04.152

Article   CAS   Google Scholar  

Charles JA (2005) Geotechnics for Building Professionals. Building Research Establishment

Charles JA, Chown RC, Watts KS, Fordyce G (2002) Brownfield Sites: Ground-related Risks for Buildings. BRE Electronic Publications

Charles JA, Skinner HD (2004) Compressibility of foundation fills. Geotech Eng 149(3):145–157. https://doi.org/10.1680/geng.149.3.145.46908

Chen C-F (2006) Applying the Analytical Hierarchy Process (AHP) Approach to Convention Site Selection J Travel Res 45(2):167–174. https://doi.org/10.1177/0047287506291593

Cinelli M, Gonzalez MA, Ford R, McKernan J, Corrente S, Kadziński M, Słowiński R (2021) Supporting contaminated sites management with Multiple Criteria Decision Analysis: Demonstration of a regulation—consistent approach. J Clean Prod 316:128347. https://www.sciencedirect.com/science/article/pii/S0959652621025610 https://doi.org/10.1016/j.jclepro.2021.128347

Cushman DJ, Driver KS, Ball SD (2001) Risk assessment for environmental contamination: an overview of the fundamentals and application of risk assessment at contaminated sites. Can J Civ Eng 28(S1):155–162

Darko A (2019) Adoption of green building technologies in Ghana: development of a model of green building technologies and issues influencing their adoption. The Hong Kong Polytechnic University. https://theses.lib.polyu.edu.hk/handle/200/9924

DEFRA; Environmental Agency (2004) CLR11: Model Procedures for the Management of Land Contamination. http://www.tunbridgewells.gov.uk/__data/assets/pdf_file/0019/52039/CRL11_EA_model_procedures_881483.pdf

Department of environmental conservation (2017) DEPARTMENT OF ENVIRONMENTAL CONSERVATION Draft Guidance on Developing Conceptual Site

Department of Toxic Substances Control (DTSC) (2008) Proven Technologies and Remedies Guidance Remediation of Metals in Soil. https://dtsc.ca.gov/wp-content/uploads/sites/31/2018/11/PT-R_Metals_Main_Text_0808-2.pdf

Donevska KR, Gorsevski PV, Jovanovski M, Peševski I (2012) Regional non-hazardous landfill site selection by integrating fuzzy logic, AHP and geographic information systems. Environ Earth Sci 67(1):121–131. https://doi.org/10.1007/s12665-011-1485-y

Elliott M (2003) Biological pollutants and biological pollution––an increasing cause for concern. Mar Pollut Bull 46 (3), 275–280. https://www.sciencedirect.com/science/article/pii/S0025326X0200423X https://doi.org/10.1016/S0025-326X(02)00423-X Accessed 13 May 2019

Environment Agency (2009) Contaminants in soil: updated collation of toxicological data and intake values for humans Cadmium The Environment Agency is the leading public body protecting and improving the environment in England and after by everyone in today’ s society, so that

Environment Agency (2015) Contaminated land exposure assessment (CLEA) tool. https://www.gov.uk/government/publications/contaminated-land-exposure-assessment-clea-tool

Environment Agency (2016) Dealing with contaminated land in England. A review of progress from April 2000 to December 2013 with Part 2A of the Environmental Protection Act 1990. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/513158/State_of_contaminated_land_report.pdfdoi:HO-POD-1K-09/02

Environment Agency (2017) Groundwater Vulnerability Maps (2017). https://data.gov.uk/dataset/ed5d127b-a2fe-47d6-a966-7c363c4d3c4c/groundwater-vulnerability-maps-2017

Environment Agency (2008) Guidance for the Safe Development of Housing on Land Affected by Contamination. NHBC and Environment Agency.

Environment Agency (2004) Model Procedures for the Management of Land Contamination. A Research Report Prepared by Casella Stanger under the Science Project SC02000028 for the UK Environment Agency. Bristol

EPA (2019) What is radon gas? Is it dangerous? EPA. https://www.epa.gov/radiation/what-radon-gas-it-dangerous#:~:text=Radon Accessed 20 Mar 2020

Greenwood P, Kuhn NJ (2014) Does the invasive plant, Impatiens glandulifera, promote soil erosion along the riparian zone? An investigation on a small watercourse in northwest Switzerland. J Soils Sediment 14(3):637–650. https://doi.org/10.1007/s11368-013-0825-910.1007/s11368-013-0825-9

Gurunadha Rao VVS, Gupta SK (2000) Mass transport modelling to assess contamination of a water supply well in Sabarmati river bed aquifer, Ahmedabad City, India. Environ Geol 39(8):893–900. https://doi.org/10.1007/s00254990003710.1007/s002549900037

Harris M, Herbert S (1994) Contaminated land: Investigation, assessment and remediation. 1st edn. Thomas Telford Publications, London

Google Scholar  

Harrison RM (2015) Pollution: causes, effects and control. Royal Society of Chemistry

Health Canada (2010) Part I: Guidance on Human Health Preliminary Quantitative Risk Assessment (PQRA), Version 2.0. http://publications.gc.ca/collections/collection_2018/sc-hc/H128-1-11-632-eng.pdf

Jefferis SA (2010) Contaminated Land and Environmental Damage: an Analysis of Current Remedial Strategies and Future Developments BT—Advances in Environmental Geotechnics. In: Yunmin Chen, Liangtong Zhan, and Xiaowu Tang (eds). Berlin, Heidelberg: Springer Berlin Heidelberg. pp. 236–247

Talaiekhozani, A., Nematzadeh, S., Eskandari, Z., Aleebrahim Dehkordi, A., & Rezania, S. (2018) Gaseous emissions of landfill and modeling of their dispersion in the atmosphere of Shahrekord, Iran. Urban Climate [online]. 24 pp. 852–862

Kanmani S, Gandhimathi R (2013) Assessment of heavy metal contamination in soil due to leachate migration from an open dumping site. Appl Water Sci 3(1):193–205

Kovacs H, Szemmelveisz K (2017) Disposal options for polluted plants grown on heavy metal contaminated brownfield lands—a review. Chemosphere 166:8–20

Kovalick WW, Montgomery RH (2017) Models and lessons for developing a contaminated site program: an international review. Environ Technol Innov 7:77–86. https://doi.org/10.1016/j.eti.2016.12.005

Laxmi KS, Shruti K, Mahendra SN, Suman S, Prem CP (2012) Fuzzy AHP for forest fire risk modeling. Disaster Prev Manag Int J 21(2):160–171. https://doi.org/10.1108/09653561211219964

Leach BA, Goodger HK (1991) Building on derelict land. PSA Specialist Services, London

Lewis GH, Johnson RG (1971) Kendall’s Coefficient of Concordance for Sociometric Rankings with Self Excluded. Sociom 34(4):496–503. http://www.jstor.org/stable/2786195doi:10.2307/2786195

Linkov I, Moberg E, Trump BD, Yatsalo B, Keisler JM (2020) Multi-criteria decision analysis: Case studies in engineering and the environment. (no place) CRC Press

Linkov I, Varghese A, Jamil S, Seager TP, Kiker G, Bridges T (2004) Multi-Criteria Decision Analysis: A Framework for Structuring Remedial Decisions at Contaminated Sites BT—Comparative Risk Assessment and Environmental Decision Making. In: Linkov I, Ramadan AB (eds). Dordrecht: Springer Netherlands. pp. 15–54

Locatelli L, Binning PJ, Sanchez-Vila X, Søndergaard GL, Rosenberg L, Bjerg PL (2019) A simple contaminant fate and transport modelling tool for management and risk assessment of groundwater pollution from contaminated sites. J Contamin Hydrol 221:35–49. https://www.sciencedirect.com/science/article/pii/S016977221830113X . Accessed 6 July 2019

Mahammedi C (2021) A Web-Based Decision Support System (DSS) for Preliminary Risk Assessment of Brownfield Sites. (no place) University of the West of England

Mahammedi C, Mahdjoubi L, Booth C, Butt T (2020a) Towards the Creation of a Decision Support System Tool for the Preliminary Risk Assessment of Brownfield Sites. WIT Trans Ecol Environ 241:257–265

Mahammedi C, Mahdjoubi L, Booth CA, Akram H, Butt TE (2020b) A systematic review of risk assessment tools for contaminated sites—current perspectives and future prospects. Environ Res 191:110180. http://www.sciencedirect.com/science/article/pii/S001393512031077X

Mahammedi C, Mahdjoubi L, Booth CA, Butt TE (2021) Framework for preliminary risk assessment of brownfield sites. Sci Total Environ 151069. https://www.sciencedirect.com/science/article/pii/S0048969721061477

Marsili D (2016) A cross-disciplinary approach to global environmental health: the case of contaminated sites. Ann Ist Super Sanita 52(4):516–523

Martin JC, Toll DG (2006) The development of a knowledge-based system for the preliminary investigation of contaminated land. Comput Geotech 33(2):93–107

McKnight PE, Najab J (2010) Mann-Whitney U Test The Corsini Encyclopedia of Psychology [online] 1. https://doi.org/10.1002/9780470479216.corpsy0524

McMahon A, Heathcote J, Carey M, Erskine A (2001) Guide to good practice for the development of conceptual models and the selection and application of mathematical models of contaminant transport processes in the subsurface National Groundwater & Contaminated Land Centre. Report NC/99/38. https://www.sepa.org.uk/media/147777/csm-guidance-from-ea.pdf

Motta FL, Stoyanov SR, Soares JBP (2017) Application of solidifiers for oil spill containment: A review. Chemosphere. 194:837–846. https://doi.org/10.1016/j.chemosphere.2017.11.103

Nathanail CP (2013) Engineering geology of sustainable risk-based contaminated land management. Q J Eng Geol Hydrogeol 46(1):6–29

Nathanail CP (2009) The role of engineering geology in risk-based land contamination management for tomorrow’s cities. Geol Soc Lond Eng Geol Spec Publ 22(1):149–158

Nathanail CP, Bardos RP (2005) Reclamation of contaminated land. John Wiley & Sons, Chichester

Nathanail J, Bardos P, Nathanail P (2011) Contaminated land management: ready reference. Land Quality Press, London

New Jersey Department of Environmental Protection (NJDEP) (2019) Technical Guidance for Preparation and Submission of a Conceptual Site Model. https://www.nj.gov/dep/srp/guidance/srra/csm_tech_guidance.pdf

Nikolaidis NP (2018) Conceptual site modelling for evaluating contaminant mobility and pump-and-treat remediation. Global NEST Int J 2(1):67–76. https://doi.org/10.30955/gnj.000114

Büyüker B (2009) A decision support tool for conceptual site model development at contaminated sites (Master’s thesis, Middle East Technical University)

Pimentel J (2010) A note on the usage of Likert Scaling for research data analysis. UMS R7D J 18(2):109–112

Pizzol L, Critto A, Agostini P, Marcomini A (2011) Regional risk assessment for contaminated sites Part 2: Ranking of potentially contaminated sites. Environ Int 37(8):1307–1320. https://www.sciencedirect.com/science/article/pii/S0160412011001553

Promentilla MAB, Furuichi T, Ishii K, Tanikawa N (2008) A fuzzy analytic network process for multi-criteria evaluation of contaminated site remedial countermeasures. J Environ Manag 88 (3):479–495. https://www.sciencedirect.com/science/article/pii/S030147970700093X

Rasli A (2006) Data analysis and interpretation-A handbook for postgraduate social scientists (+ CD). Issham Ismail (ed). 1st edn. Johor Darul Ta’zim: Penerbit UTM.

Regens JL, Obenshain KR, Travis C, Whipple C (2002) Conceptual site models and multimedia modeling: comparing MEPAS, MMSOILS, and RESRAD. Hum Ecol Risk Assess Int J 8(2):391–403. https://www.tandfonline.com/doi/pdf/10.1080/20028091056971?needAccess=true

Royston P (1992) Approximating the Shapiro-Wilk W-test for non-normality. Stat Comput 2(3):117–119. https://doi.org/10.1007/BF01891203

Sarsby RW, Felton AJ (2006) Geotechnical and Environmental Aspects of Waste Disposal Sites: Proceedings of the 4th International Symposium on Geotechnics Related to the Environment-GREEN4, 28 June–July 2004 R Sarsby and A Felton (eds). [online]. Wolverhampton: CRC Press

Saunders M, Thornhill A, Lewis P (2019) Research Methods for Business Students. Eighth Edi. Pearson Education, Harlow

Shepherd R (2020) First Time Buyers Find Out Their New Build Property Is Worthless. https://www.ladbible.com/community/uk-first-time-buyers-find-out-their-new-build-property-is-worthless-20201008 Accessed 19 Feb 2021

Sivapullaiah PV, Prasad BG, Allam MM (2009) Effect of sulfuric acid on swelling behavior of an expansive soil. Soil Sediment Contam 18(2):121–135

Skinner H, Charles JA, Tedd P (2005) Brownfield sites An integrated ground engineering strategy. BRE Bookshop, Watford

Suthersan SS, Horst J, Schnobrich M, Welty N, McDonough J (2016) Remediation engineering: design concepts. CRC Press, London

Book   Google Scholar  

Tavakol M, Dennick R (2011) Making sense of Cronbach’s alpha. Int J Med Educ 2:53

U.S. EPA (1997) Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessments. Office of Solid Waste and Emergency Response. EPA 540-R97/006

U.S. EPA (2014) Framework for human health risk assessment to inform decision making Risk Assessment Forum. Office of the Science Advisor EPA/100/R-14/001

U.S. EPA (U.S. Environmental Protection Agency). (2019). Guidelines for Human Exposure Assessment. (EPA/100/B-19/001). Washington, D.C.: Risk Assessment Forum, U.S. EPA

U.S. EPA (2001) Risk Assessment Guidance for Superfund: Volume III—Part A, Process for Conducting Probabilistic Risk Assessment. EPA 540-R-02-002. Washington, D.C.: Office of Emergency and Remedial Response

U.S. EPA (1989) Risk Assessment Guidance for Superfund Volume I Human Health Evaluation Manual (Part A). EPA/540/1-89/002. Washington, D.C.: Office of Emergency and Remedial Response

Vahidnia MH, Alesheikh AA, Alimohammadi A (2009) Hospital site selection using fuzzy AHP and its derivatives. Jo Environ Manag 90 (10):3048–3056. http://www.sciencedirect.com/science/article/pii/S0301479709001327

Vik EA, Bardos P (2003) Remediation of contaminated land technology implementation in Europe:[prepared by working group” Remediation technologies” of the concerted action” Contaminated Land Rehabilitation Network for Environmental Technologies” (CLARINET)…]. HMSO Licensing Division, Norwich

Wang G, Qin L, Li G, Chen L (2009) Landfill site selection using spatial information technologies and AHP: A case study in Beijing, China. J Environ Manag 90(8):2414–2421. http://www.sciencedirect.com/science/article/pii/S0301479708003599

Watts KS, Charles JA (1997) Treatment of compressible foundation soils. In Ground improvement geosystems Densification and reinforcement: Proceedings of the Third International Conference on Ground Improvement Geosystems London, 3–5 June 1997 (pp. 109–119). Thomas Telford Publishing

Wilson S, Oliver S, Mallett H, Hutchings H, Card G (2007) Assessing risk posed by hazardous ground gases to buildings. CIRIA Report 665

Wolfslehner B, Vacik H, Lexer MJ (2005) Application of the analytic network process in multi-criteria analysis of sustainable forest management. For Ecol Manag 207(1):157–170. http://www.sciencedirect.com/science/article/pii/S0378112704007352

Wu L, Liu Y, Liu X, Bajaj A, Sharma M, Lal R, Richnow HH (2019) Isotope fractionation approach to characterize the reactive transport processes governing the fate of hexachlorocyclohexanes at a contaminated site in India. Environ Int 132:105036

Zabeo A, Pizzol L, Agostini P, Critto A, Giove S, Marcomini A (2011) Regional risk assessment for contaminated sites Part 1: Vulnerability assessment by multicriteria decision analysis. Environ Int 37(8):1295–1306. https://www.sciencedirect.com/science/article/pii/S0160412011001310

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Mahammedi, C., Mahdjoubi, L., Booth, C. et al. Criteria for Preliminary Risk Assessment of Brownfield Site: An International Survey of Experts. Environmental Management 70 , 681–696 (2022). https://doi.org/10.1007/s00267-022-01684-x

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Case Studies

What are municipalities doing to address brownfields .

The Green Municipal Fund has a database of case studies from across Canada available  here . What follows are examples of how municipalities in Alberta are championing brownfield redevelopment.

City of Calgary

The City of Calgary’s (The City) Municipal Development Plan (MDP) includes a goal to encourage brownfield redevelopment. Redeveloping brownfields allows for the re-use of land, supports urban densification, stimulates community revitalization, increases property values and reduces health and environmental risks.

City owned sites

In 2015, redevelopment of a contaminated City-owned property in a residential community in northwest Calgary resulted in a developer buying the property with the intention of building a 4-storey mixed-use commercial/residential destination. The City also led an interim (temporary) use project that repurposed a derelict tennis court into the Twin Views Communal Garden, which is a meeting space and garden education centre for surrounding communities. A dedicated team of volunteers manages the project with oversight from the City.  

In 2016, The City's Quarry Park Recreation Centre was completed. This facility was constructed on a former quarry/industrial area and is part of the large scale brownfield redevelopment in south Calgary.

In 2012, The City acquired the former Cargill industrial site. This site operated as a grain terminal from 1914-2011 and was decommissioned shortly after operations ceased. The site, located immediately adjacent to the Bonnybrook Waste Water Treatment Plant, was purchased for the purposes of expanding the plant. In 2016, construction of a dewatering facility commenced; this is the first of several buildings that will be eventually built on this former brownfield site. 

Interim use

The City continues to pursue interim-use options on sites where it is not feasible to fully remediate the contamination, but where there are opportunities for temporary uses that facilitate economic development while providing access to the land for monitoring and potential future remediation.  For example, the City is piloting interim use of contaminated land near a light rail transit (LRT) station by locating a coffee shop in a shipping container on the land. The Southern Alberta Institute of Technology (SAIT) was engaged to conduct market research that the City hopes will demonstrate the viability of placing small businesses in modular structures on brownfield sites.

Working with the private sector

The City seeks to support redevelopment of privately owned land. There are many examples of redeveloped brownfield sites in Calgary. These sites range from former gas stations and drycleaners to large-scale sites, such as East Village (former industrial area), Garrison Woods and Currie Communities (former military base), Telus Spark Science Centre (former landfill), Quarry Park (former gravel pit/industrial area) and Deerfoot Meadows (former fertilizer plant).   To facilitate responsible brownfield redevelopment, The City conducts environmental development reviews. These reviews require applicants to demonstrate that that the environmental site conditions are suitable for the intended use. The City may also engage Alberta Health Services and Alberta Environment and Parks to ensure redevelopment will meet the applicable regulatory requirements. The City has recognized the technical challenges associated with brownfield redevelopment and has prepared the “Guidebook to Developing Contaminated Sites (2012)” to assist developers navigate this process.

Based on the lessons in redeveloping its own brownfield sites, the City seeks to support redevelopment of privately owned land by providing advice and working with Alberta Health Services and Alberta Environment and Parks to coordinate the approval process.   Many brownfield sites remain in an underutilized state, however, and The City continues to pursue opportunities for redevelopment. Two examples of sites that could potentially be redeveloped are the Former Imperial Oil Refinery Site and the West Village area.   The City is working with Imperial Oil Limited to return a former refinery site to a productive community use (e.g outdoor recreation space and public transit infrastructure). After receiving approval from Alberta Environment and Parks 2014, The City and Imperial Oil Limited began a three-year remediation project to clean up the soil and groundwater. In 2015, a water treatment system was installed to clean the groundwater. Crews also built an underground barrier wall along the riverbank to prevent the contaminants from entering the river. This work is an important step in protecting the environment and restoring the land to a point where it can be repurposed for the benefit of surrounding communities.    In 2010, the West Village Area Redevelopment Plan was plan was approved. This plan outlines a vision for redevelopment of the west end of downtown that has a long history of past and present industrial/commercial uses, including the former Canada Creosote Site. The plan area is located adjacent to the Bow River and is envisioned to be redeveloped into a mixed use community. Over the last few years, The City has completed several investigations on the former Canada Creosote site located. The most recent investigations examined the efficacy of the current containment system, provided recommendations for improvement on the water treatment system design and operations, and presented options for potential remediation of the site. The environmental investigations completed to date will help determine how the redevelopment plan could be potentially implemented.

To learn more about the City's approach to brownfield redevelopment click here  to review their Guidebook to Developing Contaminated Sites. 

City of Edmonton

The City of Edmonton is recognized nationally for its leadership in brownfield redevelopment. As is the case in most municipalities in Alberta and across Canada, former refueling sites pepper the municipality. In many cases, prohibitive costs for remediation render these sites, which sit in prominent locations, underutilized, aesthetically unpleasing, economically damaging and environmentally contaminated.

Brownfield Redevelopment Grant Program

To accelerate the return of brownfields to productive use, the City has rolled out a Brownfield Redevelopment Grant Program. A task force of City councillors worked closely with a multidisciplinary staff team to create the program, which drew on extensive research into best practices in Canada and beyond, as well as consultation with local property owners, developers and industry experts. The resulting program offers grants for all stages of brownfield remediation and includes environmental performance incentives. Initially developed with support from FCM's Green Municipal Fund, the program’s long-term funding model is based on municipal tax uplift from the increased tax revenue of a redeveloped property for a maximum of six years. 

As a result, many of the sites that the City has identified in an inventory of contaminated sites have been remediated; and this number continues to grow. The program has been recognized with awards from the Canadian Urban Institute, Alberta Municipal Affairs and FCM. A detailed profile of the program is on FCM’s website  here . Edmonton is sharing its success with other municipalities by participating in the Green Municipal Fund’s Leadership in Brownfield Renewal (LiBRe) program, a network of Canadian municipalities committed to bringing brownfield sites back into productive use. The Town of Mayerthorpe has used Edmonton’s Brownfield Redevelopment Grant program as a model for its own. 

Environmental Site Assessment Guidebook

In addition to the grant program, the City has released an  Environmental Site Assessment Guidebook  which provides an outline of the process required for Land Development Applications to determine if site conditions are suitable for their intended purpose. The guide provides clear expectations of site owners and potential developers in terms of demonstrating environmental due diligence required to meet City and provincial standards.

Brownfield Coordinator

The City has also established a Brownfield Coordinator position to act as a single point of contact for any brownfield related inquiry. The Coordinator creates networks across the City’s various departments in order to tailor support to help projects move more efficiently through the redevelopment process.

For more information visit the City of Edmonton’s brownfield redevelopment webpage .

Town of Mayerthorpe

The Town of Mayerthorpe adopted a Brownfield Redevelopment Strategy in 2015, which focuses on providing financial support to private owners of brownfield sites, and identifying and redeveloping municipally owned brownfield sites.

In 2016, Mayerthorpe launched a Brownfield Redevelopment Grant Program, which provides funding to help private landowners conduct the environmental site assessments (ESAs) required to determine whether or not a site is contaminated and what further steps need to be taken if it is. The grant program is modelled on the  City of Edmonton’s .  Up to $1,000 is available for Phase I ESAs, which involve reviewing historic and present-day uses of a site to determine whether these uses may have caused contamination.  Up to $5,000 is available for Phase II ESAs which confirm the presence, absence or level of contamination.  The grant can also be used to remove, treat or otherwise manage contamination found on the site.

In addition to promoting the grants in the local paper, the Town’s newsletter and  website , the Town also sent letters to owners of potential brownfield sites inviting them to participate in the program. To date, uptake on the program has been slow, so the Town is turning its attention to municipally-owned brownfield sites in hopes that it can lead by example and inspire private landowners to take action.

Municipally owned brownfield sites

As part of its Brownfield Redevelopment strategy, the Town is focusing on redeveloping municipally-owned sites, so that it can demonstrate the redevelopment process to the private sector. To start, the Town worked with Alberta Environment and Parks to identify and map all municipally-owned sites that are potentially contaminated. As a next step the Town has identified a couple of sites where there are good opportunities for redevelopment. For example, the Town has completed a risk assessment of properties within 300 metres of an old landfill in order to better understand the extent of contamination, how much remediation is required and feasible and what redevelopment opportunities may be appropriate for the site. While full redevelopment of the landfill and surrounding area is not possible, the Town is currently exploring interim uses such as parks and non- permanent structures (e.g. information booths) which allow for beautification and use of the sight, while at the same time providing the access needed for ongoing monitoring and management of contamination.

Leadership and networking

Brownfield redevelopment is being championed by Mayerthorpe’s Mayor and Council, who have approved dedicated funding for redevelopment initiatives. Implementation of the strategy is being led by Mayerthorpe’s CAO, who has joined the Green Municipal Fund’s  Leadership in Brownfield Redevelopment Network  to connect with brownfield experts from across Canada and access a wide array of redevelopment resources.  

Town of Okotoks

The Town of Okotoks has successfully overseen the acquisition, partition and development of a large scale brownfield site.

Former sour gas plant

In the early 2000s, a quarter section of land was donated to the Town by an oil and gas company. The site had housed a sour gas plant and sulphur storage facility. Before transferring the land, the company had done the environmental site assessments to determine the impacts of the previous use on the site and actions necessary to develop the site for another use. The company remediated the site so that it met provincial standards for industrial development.

Land dedication and partition

At the time of purchase, the site was partitioned into four areas. Approximately four acres of land that had not been contaminated was dedicated as municipal reserve and developed into a municipal park. An adjacent escarpment was dedicated as environmental reserve, which has been integrated into the Town’s corridor of natural areas. The portion of the site formally occupied by the sour gas facility, containing 57 acres, was developed into a dog park and 71 acres of the site formerly used for sulphur storage were remediated to allow for industrial development. 

Restrictive covenant

Despite having remediated the land, the company was concerned it could face future liability. Therefore, it placed a restrictive covenant on the remediated portion of the site, specifying the type of industrial development that is permissible. While the Town was pleased to be able to convert the site into an industrial park, the restrictive covenant has posed challenges. For example, the covenant allows for gas bars, but not convenience stores. The Town had to work closely with the previous owner and a fuel company wanting to build a full service gas station in order to expand the covenant to allow this type of development.  Similar additions to the covenant have been made on a site by site basis and require close communication between the municipality, the previous owner and project proponents.  Despite these challenges, over half of the industrial park has been sold and development continues. This has helped to diversify the economy, creating new jobs and increasing the municipal tax assessment base.

Community facility

Despite the previous owner’s concerns about liability, the Town was able to develop a baseball diamond on a portion of the site that had previously served as a storage facility.  A local philanthropist provided funding for the building and served as a champion for the site, convincing the previous owners to expand the covenant to allow the development of an important community facility.  

As part of the transfer agreement, the Town assumed responsibility for monitoring the site to ensure any remaining contamination does not exceed standards or migrate to non-contaminated portions of the site or adjacent lands. A schedule for monitoring wells was set out in the agreement.

Redevelopment of the land has been a long process, which continues to this day. The willingness of the municipality and company to maintain close communication throughout the process has provided the Town with economic development opportunities and community amenities.

Town of Vulcan

The Town of Vulcan is in the process of completing the remediation and redevelopment of two abandoned former bulk fuel stations. These sites represent common issues posed by brownfields; they were contaminated, under-used and visually unappealing. Vulcan wanted to re-purpose the sites and develop a Solar Park, the first of its kind in Canada. The Park is located in downtown Vulcan, is highly visible, and will produce electricity while at the same time providing an aesthetically pleasing space for the community to gather.

Procurement of the two sites was the most difficult and time-consuming portion of the process, as liability issues and contamination created hurdles for the Town. The sites were remediated by soil replacement and will be monitored for the life of the park to ensure that any residual contamination does not migrate to other properties or to the surface of the site. Once procurement and remediation were accomplished, installation of the solar components took place in the spring of 2016, and early summer 2016 saw germination of the grass. The design and development of the Vulcan Solar Park involved local students, and the site will include learning modules on solar power to continue to educate after its completion. Funding for the site was received from Alberta Energy Innovation Fund and partnership with two private companies.

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Impact story

Case study: Unlocking data on brownfield sites

There are over 1.1 million households in England on the social housing waiting list, even though there is enough brownfield land to build an estimated 1 million homes. Engineering and design consultancy company Atkins have been identify how well currently open datasets can support developing insights into contamination of brownfield sites

Thu Aug 6, 2020

There are over 1.1 million households in England on the social housing waiting list, even though there is enough brownfield land to build an estimated 1 million homes. 

In 2020, engineering and design consultancy company Atkins undertook a discovery project, funded by Lloyds Register Foundation and supported by the Open Data Institute, to identify how well currently open datasets can support developing insights into contamination of brownfield sites, and comparing that approach with existing commercial and unused datasets.

Back in March 2020, the Lloyd’s Register Foundation and the ODI offered a stimulus fund to help projects to increase access to data and drive innovation in the engineering sector – with an emphasis on improving safety, and this is one of them.

Key facts and figures

• Critical sources of contamination are currently only found in non-open datasets.
• Datasets already exist that could be made more open to help improve decision making and reduce costs associated with developing brownfield sites, particularly for smaller developers, and help address the national housing crisis.
• There is unused data held by companies like Atkins and their customers which, if shared in ways that built trust, could unlock further value.
• There is an opportunity for industry to collaborate and unlock the power of location data about brownfield land contaminants. These conversations will be important to support Government housing commitments and deliver the ambitions in the UK Geospatial Data Strategy .

View Atkin's latest report: Improving safety in brownfield development

What was the challenge?

Currently there are over 1.1 million households in England on the social housing waiting list, even though in England there is enough brownfield land to build an estimated 1 million homes. One of the biggest blockers in developing these sites are unknown ground conditions, especially where there is the potential for contaminated land to pose a health risk.

Ground conditions within brownfield land are known to have an impact on health and safety. For example, developing on or near a historic landfill can put workers developing the site at risk (e.g. encountering hazardous materials, such as asbestos) as well as causing health issues in residents (e.g. from the gas generated from breakdown of waste materials).

This discovery research project led by Atkins aimed to identify how well currently open datasets can support developing insights into contamination of brownfield sites, and comparing that approach with existing commercial and unused datasets.

Even though we know that the ground conditions on brownfield sites can have a big impact on health and safety, the levels of contamination within the ground are not yet being recorded or made available in the same systematic way. For example, often these datasets are under commercial terms, which may make it harder for some to access.

The creation of data for specific projects or surveys being used once and never again is a challenge faced across many working on the built environment

Repeated surveys of the same ground by different developers are a typical example of this problem. A combination of data being held on a project by project basis, a lack of visibility of data acquired and difficulty gaining access for reuse mean that developers spend time and money repeating data collection activities.

The creation of data for specific projects or surveys being used once and never again is a challenge faced across many working on the built environment. The number of initiatives in place looking at different models for sharing data indicate the scale of the challenge and the potential value to gain .

How are Atkins solving the problem?

Building on previous and existing initiatives (such as Project Iceberg and National Underground Assets Register ), Atkins framed their discovery project around three challenges to make data about underground infrastructure accessible.

• Creating an inventory of data that could determine whether brownfield land would be classed as contaminated.
• Identifying use cases to demonstrate how open, shared and closed data about brownfield sites could reduce unknown risks on site.
• Creating a framework to encourage increased sharing of data about brownfield sites and contaminated land.

To ensure they had a common view of data sources, the team used ODI guidance to create a data inventory. They drew on the numerous projects Atkins are involved in each year that require access to data about brownfield sites or understanding levels of land contamination. The team interrogated their internal database to identify data from relevant past projects. The search included 1500 projects from the public and private sector and highlighted the range of organisations holding data on this subject.

Focusing on two use cases, the team examined the data available to understand contaminants in land, and identify gaps at site specific and national levels.

• At site specific level, using the example of a gasworks site, the team were able to understand the impact of using only open data or a combination of open and proprietary data to understand the risk of contaminants on site.
• To understand risk at a national level the team used data on ground investigations and environmental monitoring held in their OpenGround system (a cloud-based platform). This data is only available on a project by project basis so the team extracted the relevant layers, prepared the data into a standardised format, and aggregated it into a national dataset for their use.

To understand risk at a national level the team took a novel approach of looking at individual survey data and exploring how it could be aggregated to help provide more insights into land contamination.

In forming a common view of data sources, the team created the first open access land contamination data inventory

In forming a common view of data sources, the team created the first open access land contamination data inventory and published Atkins’ first public Github repository .  They chose to publish these outputs openly to encourage collaboration across the community to maintain and improve the data inventory. The Github repository hosts both the inventory and the code developed to access multi-project data via OpenGround Web API to enable scale analysis of existing data.

What was the impact of taking this approach?

Government policy commits to both supporting smaller developers financially to encourage innovation in the kind of homes that are built and the way they are delivered and to:

“work with local leaders to regenerate local brownfield land and deliver the homes their communities need on land which is already developed .

We know the ground conditions on brownfield sites can have a big impact on health and safety, site development costs and design constraints, yet these data are often only available under commercial terms at cost, which can make it harder for smaller developers, who often have fewer resources, to access them.

The findings of both the national and site specific use cases investigated by Atkins, demonstrate that using only currently open sources of data leaves a gap in understanding  health and safety risks. For example, site specific data omitted to identify the site had previously been used as a gasworks, and therefore posed an increased risk to safety and added costs for the developer.

The findings of both the national and site specific use cases investigated by Atkins, demonstrate that using only currently open sources of data leaves a gap in understanding  health and safety risks

Making more of this data openly available could drive down costs, by reducing the need for multiple surveys of the same ground and through earlier identification of site constraints (contamination risks and potential remediation required), thus reducing development costs and helping to deliver government housing commitments .

This project highlights the opportunity for industry to collaborate to unlock the power of location data about brownfield land contaminants. Due to the variation in the provision of information about reuse of data, Atkins have opened up conversations with clients about data reuse & licensing permissions. Initial discussions have begun with key-stakeholders in this sector including AGS, Geospatial Commission and Bentley and should support delivery of the ambitions in the UK Geospatial Data Strategy . If organisations within the sector are able to align on the way they will access, use and share data this could make things much more streamlined, improving efficiency and reducing costs on projects. The network effects of this could be widely felt.

This project highlights the opportunity for industry to collaborate to unlock the power of location data about brownfield land contaminants.

Existing survey data is not well standardised, because it is expected to have limited use. Through some even simple standardisation, it could be possible to reuse this information in new ways, including the creation of an aggregate dataset. This project has highlighted some of the initial areas of focus and areas for further work to maximise value from this data.

What lessons did they learn?

This discovery project threw up a number of challenges and learning points.

• There are a vast range of public and private sector organisations holding data on this subject, therefore accessing all the available data isn’t straightforward. It can often be quicker and easier to buy environmental data from a reseller (e.g. Landmark and Groundsure) rather than approach each steward individually, as they have already completed the work to collate / aggregate the relevant information. However, purchasing data in this way can be costly, and could limit opportunities for smaller developers.
• Consultancy firms often purchase the same data multiple times for use on different projects, this is due to a combination of a lack of visibility of data acquired internally, so projects aren’t aware of what is already available, and unclear information on reuse. Our manifesto outlines what is required to treat data as an asset to maximise its value to individual firms, as well as wider society.
• Local Authority Planning Portals contain rich historic information however often data formats are proprietary and it is difficult to extract and analyse the data. The team needed to use machine learning to pull out historic data and information from pdf’s.
• Data standardisation is very much project by project, there is no overarching industry strategy. Due to this, it was not initially possible to easily select and extract all relevant data, across the range of projects, in one go. To overcome this challenge the team tailored commands within an API to retrieve the data. Retrieval of data is a common challenge within consultancies; consultants routinely charge for time under project delivery, which often doesn’t account for data management time, therefore there is often no dedicated resource within organisations to tackle data management issues and they are picked up informally by hobbyists. Investing in a stronger data infrastructure, as set out in our manifesto , with agreed standards and guidance for the access, use and sharing of data, will ensure organisations and communities are able to access and maximise value from it.
• Data about contaminated land can be highly technical and difficult to understand for non specialists. Involving a domain specialist within the team was critical in terms of understanding practices in the field, and terminology used within the data. The team found they drew on this domain knowledge much more than originally anticipated. This also raised questions about how an aggregated dataset, or sharing of survey data more widely, might need to be done cautiously so that it is properly interpreted.

Key tips and advice

Create a data inventory

Focussing on the purpose of the inventory, for example to address a particular challenge or topic, will ensure it is as useful as possible and will contribute to a stronger data infrastructure. Involving domain experts will also help with identifying the key information to capture. For example, in this case staff experienced in completing Preliminary Risk Assessment (PRA) desk study reports input to the inventory scope.

Invest in data science skills and knowledge on projects

It took a lot of technical expertise to access, use and share data within this project, requiring specialist data skills and knowledge in conjunction with domain expertise. Tackling these types of challenges with a multi-discipline research team increases the skills and knowledge available to a project. Building data skills required for the future of the profession as a key activity outlined in our manifesto for sharing engineering data. There is a role for professional bodies, private sector companies, universities and research organisations to include these skills in their curriculum and professional development activities.

Communicate and collaborate early

Due to the range of organisations involved in stewarding data on land contamination, communication and collaboration across the industry to maximise utility of data is key. Include a range of stakeholders within the land contamination business relevant to your project (e.g the AGS Committee, laboratories, contractors, consultancies, regulatory bodies, the British Geological Survey, local planning authorities and industry bodies) to agree a unified data structure and robust standards. Including the sharing of data in contracts, so everyone is clear on their responsibilities as projects are agreed, could also be another way to maximise value from data across the geotechnical and geo-environmental industry and its stakeholders. The importance of stewarding data for collaboration is highlighted in our manifesto .

What’s next?

This project has been a catalyst for internal conversation at Atkins about the value of an open approach to access and reuse of data. Atkins are keen to continue the conversation on unlocking data about brownfield land. They plan to continue;

• Engagement with the Geospatial Commission, working with them to align this research with the four missions outlined in the Geospatial Strategy 2020-2025. These further goals will likely be aligned to the development of housing specifically.
• Working with the AGS to improve their data formatting and opening up their framework to make it more accessible to a wider audience.
• Opening up conversations with clients about how they can open up data on their sites and contribute towards an open data ‘future’.
• Further research into the other datapoints available in the AGS data currently stored in the OpenGround database.
• Promoting community contribution to the contaminated land data inventory . For example, by establishing an agreed ranking system to indicate the level of importance of datasets to the community.

Get involved

If you want to get in touch to speak to the team involved in the project or to discuss a project you’re running yourself which you need some support with, please get in touch

View the Atkins 'ODI Fridays' lunchtime lecture