Contemporary design, operation, and monitoring of potable reuse systems

Water scarcity driven by population growth, lack of conventional supplies, and climate change impacts have resulted in increasing interest worldwide in drinking water augmentation using treated wastewater effluents. Potable reuse can occur indirect or direct, but is also practiced in many places as ‘de facto reuse’, where upstream wastewater discharge occurs to drinking water supplies. With this increasing recognition of potable reuse, there is very limited guidance and standardization for proper design and operation of potable reuse schemes that is protective of public health. This study provided guidance on contemporary approaches for the design, operation, and monitoring of potable reuse schemes, including source water characterization and source control approaches; linking water quality treatment performance goals to health risks; risk mitigation strategies including the design principles of multiple barriers for microbial and chemical contaminants; assessing system reliability and fail-safe design approaches; and, finally, monitoring strategies for process performance and compliance.

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Drinking water vulnerability in less-populated communities in Texas to wastewater-derived contaminants

npj Clean Water ◽

10.1038/s41545-019-0043-0 ◽

2019 ◽

Vol 2 (1) ◽

Author(s):

Thuy T. Nguyen ◽

Paul K. Westerhoff

Keyword(s):

Drinking Water ◽

Drinking Water Treatment ◽

Treated Wastewater ◽

Potable Reuse ◽

Advanced Technologies ◽

The Usa ◽

Water Vulnerability ◽

De Facto Reuse ◽

Lower Population ◽

Model Approach

Abstract De facto potable reuse occurs when treated wastewater is discharged upstream of drinking water treatment plants (DWTPs) and can lead to contaminants of emerging concern (CECs) occurring in potable water. Our prior research, focusing on larger communities that each serve >10,000 people across the USA, indicates that elevated de facto reuse (DFR) occurs in Texas, and thus we added to our model DWTPs serving smaller communities to understand their vulnerability to CECs. Here, we show that two-thirds of all surface water intakes in Texas were impacted by DFR at levels exceeding 90% during even mild droughts, and under average streamflow DFR levels range between 1 and 20%. DWTPs serving lower population communities (<10,000 people) have higher DFR levels, and fewer than 2% of these communities have advanced technologies (e.g., ozone, activated carbon) at DWTPs to remove CECs. Efforts to improve water quality in these less populated communities are an important priority. The model approach and results can be used to identify prioritization for monitoring and treatment of CECs, including in underserved communities, which normally lack knowledge of their impacts from DFR occurring within their watersheds.

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A Mechanistic Model to Assess the Fate of Naphthalene and Benzo(a)pyrene in a Chilean WWTP

Processes ◽

10.3390/pr9081313 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1313

Author(s):

Antonia Arroyo ◽

Fabián Provoste ◽

Montserrat Rodríguez ◽

Ana L. Prieto

Keyword(s):

Wastewater Treatment Plants ◽

Mechanistic Model ◽

Treated Wastewater ◽

Urban Centers ◽

Potable Reuse ◽

Conventional Activated Sludge ◽

Regulatory Standards ◽

Polycyclic Aromatic ◽

De Facto Reuse

Polycyclic aromatic hydrocarbons (PAHs) are a family of organic compounds of widespread presence in the environment. They are recalcitrant, ubiquitous, prone to bioaccumulation, and potentially carcinogenic. Effluent from wastewater treatment plants (WWTPs) constitutes a major source of PAHs into water bodies, and their presence should be closely monitored, especially considering the increasing applications of potable and non-potable reuse of treated wastewater worldwide. Modeling the fate and distribution of PAHs in WWTPs is a valuable tool to overcome the complexity and cost of monitoring and quantifying PAHs. A mechanistic model was built to evaluate the fate of PAHs in both water and sludge lines of a Chilean WWTP. Naphthalene and benzo(a)pyrene were used as models of low-MW and high-MW PAHs. As there were no reported experimental data available for the case study, the influent load was determined through a statistical approach based on reported values worldwide. For both naphthalene and benzo(a)pyrene, the predominant mechanism in the water line was sorption to sludge, while that in the sludge line was desorption. Compared to other studies in the literature, the model satisfactorily describes the mechanisms involved in the fate and distribution of PAHs in a conventional activated sludge WWTP. Even though there is evidence of the presence of PAHs in urban centers in Chile, local regulatory standards do not consider PAHs in the disposal of WWTP effluents. Monitoring of PAHs in both treated effluents and biosolids is imperative, especially when considering de facto reuse and soil amendment in agricultural activities are currently practiced downstream of the studied WWTP.

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Performance-Based Planning to Reduce Flooding Vulnerability Insights from the Case of Turin (North-West Italy)

Sustainability ◽

10.3390/su13105697 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5697

Author(s):

Stefano Salata ◽

Silvia Ronchi ◽

Carolina Giaimo ◽

Andrea Arcidiacono ◽

Giulio Gabriele Pantaloni

Keyword(s):

Urban Areas ◽

Risk Mitigation ◽

Climate Change Impacts ◽

Mitigation Strategies ◽

Decision Makers ◽

Revision Process ◽

North West ◽

Run Off ◽

Flooding Risk

Climate change impacts urban areas with greater frequency and exposes continental cities located on floodplains to extreme cloudbursts events. This scenario requires developing specific flooding vulnerability mitigation strategies that improve local knowledge of flood-prone areas at the urban scale and supersede the traditional hazard approach based on the classification of riverine buffers. Moreover, decision-makers need to adopt performance-based strategies for contrasting climate changes and increasing the resilience of the system. This research develops the recent Flooding Risk Mitigation model of InVEST (Integrated Evaluation of Ecosystem Services and Trade-off), where cloudburst vulnerability results from the soil’s hydrological conductivity. It is based on the assumption that during cloudburst events, all saturated soils have the potential for flooding, regardless of the distance to rivers or channels, causing damage and, in the worst cases, victims. The model’s output gives the run-off retention index evaluated in the catchment area of Turin (Italy) and its neighborhoods. We evaluated the outcome to gain specific insight into potential land use adaptation strategies. The index is the first experimental biophysical assessment developed in this area, and it could prove useful in the revision process of the general town plan underway.

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Bubble concept for sporting tournaments during the COVID-19 pandemic: Football Club World Cup

BMJ Open Sport & Exercise Medicine ◽

10.1136/bmjsem-2021-001126 ◽

2021 ◽

Vol 7 (2) ◽

pp. e001126

Author(s):

Andrew Massey ◽

Sarah Lindsay ◽

Dexter Seow ◽

Jonny Gordon ◽

David J Lowe

Keyword(s):

Risk Mitigation ◽

Case Series ◽

Mitigation Strategies ◽

Symptom Reporting ◽

World Cup ◽

Football Club ◽

Monitoring Strategies ◽

Hygiene Measures ◽

Viral Illness ◽

Prospective Case Series

ObjectivesTo report the person-to-staff transmission of COVID-19 with the implementation of a bubble concept that included testing, hygiene, distancing and monitoring strategies to mitigate risks.MethodsA prospective case series included all staff on-site involved in the Football Club World Cup. The tournament was conducted within ‘bubbles’. All personnel travelling to the tournament were required to be in possession of a negative RT-PCR test within 72 hours of arrival and subjected to a testing schedule during the tournament. Each location was assigned a COVID-19 protocol enforcement officer to ensure adherence to regular testing, hygiene measures, physical distancing and daily symptom reporting (via ScribePro app).ResultsThe study involved 70 recruited staff with a combined 1321 test days on the symptom checker app. The mean number of days completed on the symptom checker app was 18.87 days (range: 7–28). Of the five questions asked as part of the daily symptom checker, only one was answered positively (0.015%). This individual was isolated, assessed within 20 min and tested. The initial diagnosis was likely a non-COVID-19-related viral illness. Further testing returned three negative tests during the remainder of the tournament.ConclusionsThere was no person-to-staff transmission of COVID-19 during the tournament within our sample. The organisation of a sporting tournament during the COVID-19 pandemic is possible with risk mitigation strategies. These strategies include setting up a bubble with regular testing, hygiene measures, physical distancing and daily symptom reporting.

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Implications of Climate Change Impacts on Regional Maize Production in the United States: Risk Mitigation Strategies and Food Security

International Journal of Environmental Science and Development ◽

10.7763/ijesd.2013.v4.391 ◽

2013 ◽

pp. 446-451 ◽

Cited By ~ 3

Author(s):

Xiang Li ◽

Nobuhiro Suzuki

Keyword(s):

Climate Change ◽

United States ◽

Food Security ◽

Risk Mitigation ◽

Climate Change Impacts ◽

The United States ◽

Mitigation Strategies ◽

Maize Production ◽

Risk Mitigation Strategies

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Mine Hoist Safety: Regulations and Proposed Improvements to Risk-Mitigation Strategies

CIM Journal ◽

10.15834/cimj.2016.27 ◽

2016 ◽

Vol 7 (4) ◽

Cited By ~ 1

Author(s):

B. Galy ◽

L. Giraud

Keyword(s):

Risk Mitigation ◽

Mitigation Strategies ◽

Safety Regulations ◽

Risk Mitigation Strategies ◽

Mine Hoist

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Sequential risk mitigation and the role of natural recovery in contaminated sediment projects

Water Science & Technology ◽

10.2166/wst.1998.0769 ◽

1998 ◽

Vol 37 (6-7) ◽

pp. 331-336 ◽

Cited By ~ 3

Author(s):

Stephen Garbaciak ◽

Philip Spadaro ◽

Todd Thornburg ◽

Richard Fox

Keyword(s):

Lower Cost ◽

Risk Mitigation ◽

Management Strategies ◽

Source Control ◽

Contaminated Sediment ◽

Practical Observation ◽

Ecosystem Recovery ◽

Natural Recovery ◽

Natural Processes

Sequential risk mitigation approaches the remediation of contaminated sediments in three phases designed to: (1) immediately reduce the ecological and human health risks associated with high levels of contamination, using methods such as the confinement or capping of high-risk materials; (2) reduce the risks associated with moderate levels of pollution to a minimum, on a less urgent schedule and at a lower cost; and (3) address areas of limited contamination through a combination of natural recovery and enhanced natural recovery (to aid or speed those natural processes). Natural recovery, the reduction of contaminant concentrations through natural processes, is based on the practical observation that overall ecosystem recovery appears to be largely a function of time. Sediment decomposition and the mixing of new and old sediments by bottom-dwelling organisms can both contribute to reduced contaminant concentrations. Knowledge of these processes--sediment decomposition, sediment mixing by bottom-dwelling organisms, and chemical residence time is critical in the development of appropriate ecosystem recovery and waste management strategies. Evaluations to support natural recovery predictions are designed to collect and evaluate information necessary to determine whether surface sediment chemical concentrations, with adequate source control, will reach the cleanup standards within a ten-year period.

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Proactive Actions Based on a Resilient Approach to Urban Seismic Risk Mitigation

The Open Construction and Building Technology Journal ◽

10.2174/1874836802014010321 ◽

2020 ◽

Vol 14 (1) ◽

pp. 321-335

Author(s):

Marco Vona

Keyword(s):

Urban Planning ◽

Emergency Management ◽

Seismic Risk ◽

Risk Mitigation ◽

Housing Stock ◽

Mitigation Strategies ◽

Housing System ◽

Management Tools ◽

Natural Risk ◽

Seismic Risk Mitigation

Background: Seismic risk mitigation is an important issue in earthquake-prone countries, and needs to be solved in those complex communities governed by complex processes, where urban planning, socioeconomic dynamics, and, often, the need to preserve cultural assets are present simultaneously. In recent years, due to limited financial resources, mitigation activities have often been limited to post-earthquake events, and only a few in periods of inactivity, particularly in urban planning. At this point, a significant change in point of view is necessary. Methods: The seismic risk mitigation (and more generally, natural risk mitigation) must be considered as the main topic in urban planning and in the governance of communities. In fact, in several recent earthquakes, significant socioeconomic losses have been caused by the low or lack of resilience of the communities. This is mainly due to the high vulnerability of private buildings, in particular, housing units. Results: Therefore, in recent years, several studies have been conducted on the seismic resilience of communities. However, significant improvements are still needed for the resilience assessment of the housing stock, both qualitatively and quantitatively. In this study, which is applied to the housing system, a proposal regarding a change in urban planning and emergency management tools based on the concept of resilience is reported. As a first application, a case study in Italy is considered. Conclusion: The proposal is focused on defining and quantifying the improvement of the resilience of the communities and this must be obtained by modifying the current Civil Protection plan. New tools are based on a new resilience community plan by encompassing urban planning tools, resilient mitigation strategies, and consequently, emergency management planning.

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