Operation & Maintenance

Introduction Summary The need to handle increasing amounts of data while improving capital and operational efficiencies has directed the attention of the water sector towards advanced digital tools such as operational digital twins. Digital twins can be seen as combinations of models and real-time data that provide a digital representation of a specific part of the water system’s behaviour. The aim of this white paper is to highlight how digital twins can help the water industry to improve performance of its infrastructure. The white paper presents two case studies where online digital twins are used for operational decision support: one in a sewer network and the other in a water resource recovery facility. Due to advances in instrumentation and the increasing availability of online data and computing capacity for utilities (e.g. via cloud computing), the development of digital twins has recently attracted large interest in the urban water sector. This interest is primarily driven by two trends in our industry: i) the increasing amount of data available at our facilities; and ii) the business drivers around both improved capital and operational efficiency targets. The amount of data available at many facilities now exceeds the amount that most operational staff can utilise in their day-to-day operations. Digital twins can take those data and present them in terms that staff can use effectively on a day-to-day basis (Garrido-Baserba et al., 2020). The second driver towards efficiency relates to the ability of a digital twin to go beyond conventional PID (i.e. proportional–integral–derivative) control, using model-based control and data-driven optimisation. This improvement has implications for capital expenditure since more reliable control can result in reductions in conservatism, and thus lower capital expenditure (Stentoft, 2020).

Introduction This Operation and Maintenance (O&M) Manual is the basic reference for the operation and maintenance of the equipment and processes that comprise the Central Facilities Area (CFA) Sewage Treatment Plant (STP) at the Idaho National Laboratory (INL) Site. The manual is required by the facility’s Municipal Wastewater Reuse Permit (LA-000141-03). Managers, operators, and maintenance personnel use this manual and associated company and equipment manufacturer’s procedures to operate the STP in support of CFA activities and permit requirements. The Laboratory Instructions (LI) listed below provide additional step-by-step instructions for operating specific components of the STP and laboratory equipment. LIs are prepared and cancelled as needed to provide directions for operating and maintaining STP equipment.

INTRODUCTION Purpose of Good Practice Guide The catchment-to-consumer risk-based approach to the production of microbially-safe drinking water, which is detailed in the Framework for Management of Drinking Water Quality (the Framework) that underpins the Australian Drinking Water Guidelines (ADWG), is based on the identification and control of risks to the quality of drinking water supplied to consumers. This reduction in risk is achieved by implementing a multiple barrier approach, where a number of different barriers to contamination are put in place, from the catchment to the consumer. Whilst the risk management process stretches all the way from catchment to consumer, in practice the majority of risks are managed through the use of various water treatment processes. Most Australian source waters require some level of treatment prior to being supplied to consumersas drinking water. The level of treatment required to produce microbially-safe drinking water will be a function of the quality of the source water and should be informed by a system-specific risk assessment process that is consistent with the approach described under Element 2 (Assessment of the drinking water supply system) of the Framework. The production of microbially-safe drinking water is difficult to consistently achieve, and requires constant vigilance, as well as well-maintained and operated water treatment processes (Element 3 (Preventive measures for drinking water quality management) and Element 4 (Operational procedures and process control) of the Framework). Within this risk-based approach, the purpose of this Guide is to provide concise advice on good practice preventive measures for the management of drinking water treatment processes and the distribution of this treated water to consumers. This is achieved by providing targets, both numerical and observational, for the various activities that should be undertaken in order to produce microbiallysafe drinking water. The Guide is not intended to be a risk assessment tool; it assumes that a system-specific risk assessment has been done, and that the treatment and distribution processes that are present are suitable for the assessed level of microbial risk. The Guide is therefore focused on the optimisation, management and control of existing water supply systems. The advice in this Guide is applicable to existing water supply systems and is intended to help water utilities produce microbially-safe drinking water under existing arrangements; it will also assist utilities meet any future microbial health-based targets that may be includes in the ADWG. The Guide is presented in a tabular format for simplicity. The table is broken into sections that relate to the key control points in typical water treatment and distribution systems.