Full-Scale Implementation of Sequential Chlorination to Produce California Title 22 Recycled Water

Abstract Membranes are an important barrier used in recycled water treatment plants for pathogen removal. Understanding performance over operational life is important to inform membrane replacement. In this study, full scale virus challenge testing was conducted on newly commissioned membranes to validate virus log removal values for accreditation. After six years of operation, the membrane integrity was repeated to ensure compliance with the state regulatory health authority and gain an understanding of the asset's condition. Membrane performance was assessed using a combination of complementary tests including membrane autopsy and chemical tolerance testing to assess individual modules and selected membrane fibres, followed by a full scale virus challenge for whole of unit assessment. The results demonstrated that the aged membrane fibres were intact and had not been affected by long-term exposure to chlorine, which provides valuable information for membrane asset replacement strategies.

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Influence of treatment processes and disinfectants on bacterial community compositions and opportunistic pathogens in a full-scale recycled water distribution system

Journal of Cleaner Production ◽

10.1016/j.jclepro.2020.123034 ◽

2020 ◽

Vol 274 ◽

pp. 123034

Author(s):

K.C Bal Krishna ◽

Arumugam Sathasivan ◽

Andrzej Listowski

Keyword(s):

Bacterial Community ◽

Distribution System ◽

Water Distribution ◽

Water Distribution System ◽

Full Scale ◽

Opportunistic Pathogens ◽

Recycled Water ◽

Treatment Processes

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Developing a regional recycled water program in Southern California

Water Practice & Technology ◽

10.2166/wpt.2019.042 ◽

2019 ◽

Vol 14 (3) ◽

pp. 570-578

Author(s):

R. S. Trussell ◽

G. Lai-Bluml ◽

M. Chaudhuri ◽

G. Johnson

Keyword(s):

Water Resources ◽

Los Angeles ◽

Membrane Filtration ◽

Southern California ◽

Control Plant ◽

Full Scale ◽

Recycled Water ◽

The Usa ◽

Treatment Train ◽

Water District

Abstract The Metropolitan Water District of Southern California (Metropolitan) and the Sanitation Districts of Los Angeles County (Sanitation Districts) are exploring the potential of a Regional Recycled Water Program (RRWP) to beneficially reuse water currently discharged to the Pacific Ocean. The program would consist of a new advanced water treatment (AWT) facility at the Sanitation Districts' Joint Water Pollution Control Plant (JWPCP) in Carson, California, USA, capable of producing an ultimate flow of 581 MLD (150 MGD). The full-scale facility would treat effluent from the JWPCP using an AWT train comprising a membrane bioreactor (MBR), followed by reverse osmosis (RO) and ultraviolet light advanced oxidation (UV/AOP). After MBR-RO-UV/AOP treatment, the treated water would be distributed to groundwater basins in Los Angeles and Orange counties to recharge their aquifers. This program would diversify the region's water resources and significantly contribute to long-term water supply targets outlined in Metropolitan's Integrated Water Resources Plan. A feasibility study for the RRWP was completed in 2016, confirming its technical viability. Currently, Metropolitan and the Sanitation Districts recently completed conceptual planning studies to investigate implementation options for a full-scale program, and constructed a 1.9 MLD (0.5 MGD) AWT demonstration facility. Although large facilities employing membrane filtration (MF)-RO-UV/AOP are currently permitted and operating in California, there are no facilities using an MBR-RO-UV/AOP train. The AWT demonstration facility – the Regional Recycled Water Advanced Purification Center – will build on recent research in Australia and the USA to develop a regulatory strategy to incorporate MBR into a potable reuse advanced treatment train.

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Relation of Statistically Significant, Abnormal, and Typical WAIS-R VIQ-PIQ Discrepancies to Full Scale IQs

European Journal of Psychological Assessment ◽

10.1027//1015-5759.16.2.107 ◽

2000 ◽

Vol 16 (2) ◽

pp. 107-114 ◽

Cited By ~ 3

Author(s):

Louis M. Hsu ◽

Judy Hayman ◽

Judith Koch ◽

Debbie Mandell

Keyword(s):

Graphical Method ◽

The United States ◽

Full Scale ◽

True Score ◽

Absolute Value ◽

Normative Population ◽

The Us ◽

The Mean ◽

And Performance ◽

Quadratic Models

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.

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A Modification of the Payne-Jones Method of Identifying Abnormal Differences in WISC-R Performance and Verbal IQ's

European Journal of Psychological Assessment ◽

10.1027/1015-5759.12.1.27 ◽

1996 ◽

Vol 12 (1) ◽

pp. 27-32 ◽

Cited By ~ 1

Author(s):

Louis M. Hsu

Keyword(s):

Full Scale ◽

True Score ◽

Verbal Iq ◽

Score Difference ◽

The Difference ◽

And Performance

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.

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