Saisai Gao Articles | Environmental XPRT

EPA’s Process for Assessing and Controlling Toxic Chemicals Remains on GAO’s High-Risk List

The U.S. Government Accountability Office (GAO) released on March 6, 2019, a report entitled High-Risk Series: Substantial Efforts Needed to Achieve Greater Progress on High-Risk Areas. GAO’s high-risk program identifies government operations with vulnerabilities to fraud, waste, abuse, and mismanagement, or in need of transformation to address economy, efficiency, or effectiveness ...

Mar. 9, 2019

By Bergeson & Campbell, P.C.

Abundance of PAO and GAO Bacteria in a Well Performing Enhanced Biological Phosphorus Removal System

ABSTRACT Interactions between PAOs and GAOs in EBRP systems have been reported as one of the major causes of EBPR failure. This study investigated the abundance of the PAO species Candidatus accumulibacter phosphatis and the GAO species Candidatus competibacter phosphatis in a fullscale well performing EBPR system. General changes in the microbial population of the system were also assessed. ...

Oct. 13, 2007

By Water Environment Federation (WEF)

Washington Watch - GAO Recommends TSCA Improvements, and a Senate Bill Responds with a Proposal

In June, the Government Accountability Office (GAO) issued a report critical of the federal government’s ability under the Toxic Substances Control Act (TSCA) to assess and prevent risks from new and existing chemical substances. Entitled Chemical Regulation: Options Exist to Improve EPA's Ability to Assess Health Risks and Manage Its Chemical Review Program,1 the report is not the first (or ...

Dec. 1, 2005

By Bergeson & Campbell, P.C.

GAO Reviews EPA`s IRIS Assessment Efforts and Implementation of TSCA Reforms

On March 4, 2019, the U.S. Government Accountability Office (GAO) published a report titled Chemical Assessments: Status of EPA’s Efforts to Produce Assessments and Implement the Toxic Substances Control Act. The report describes the extent to which the U.S. Environmental Protection Agency’s (EPA) Integrated Risk Information System (IRIS) Program has addressed identified challenges ...

Mar. 6, 2019

By Bergeson & Campbell, P.C.

GAO Report on Missouri River Flood and Drought

Introduction The Missouri River stretches from western Montana to St. Louis, Missouri. The Corps manages six dams and reservoirs on the river to provide flood control and for other purposes, such as recreation and navigation. The Corps bases reservoir release decisions on the guidance in the Master Manual. In the 2011 flood, the Corps managed the highest runoff volume since 1898, resulting in ...

Oct. 1, 2014

By IWA Publishing

Could nitrite/free nitrous acid favour GAOs over PAOs in enhanced biological phosphorus removal systems?

Enhanced biological phosphorus removal (EBPR) normally occurs together with nitrogen removal in wastewater treatment plants (WWTPs). In recent years, efforts have been devoted to remove nitrogen via the nitrite pathway (oxidation of ammonia to nitrite and reduction of nitrite to nitrogen gas without going through nitrate), reducing the requirement for carbon and oxygen in the plant. However ...

Jan. 1, 2011

By IWA Publishing

GAO Recommends TSCA Improvements, and a Senate Bill Responds with a Proposal

In June, the Government Accountability Office (GAO) issued a report critical of the federal government’s ability under the Toxic Substances Control Act (TSCA) to assess and prevent risks from new and existing chemical substances. Entitled Chemical Regulation: Options Exist to Improve EPA's Ability to Assess Health Risks and Manage Its Chemical Review Program,1 the report is not the first (or ...

Dec. 1, 2005

By Bergeson & Campbell, P.C.

Recent federal developments in chemical regulation, pesticides, occupational health and safety and related areas

On January 22, 2009, the Government Accountability Office (GAO) issued a report adding the U.S. Environmental Protection Agency’s (EPA) Integrated Risk Information System (IRIS) to a list of federal programs, policies, and operations that are at a “high risk” for waste, fraud, abuse, and mismanagement. The report claims that the EPA program was added to the list because IRIS is at risk of ...

Feb. 23, 2009

By Bergeson & Campbell, P.C.

Environmental compliance enforcement from the government accountability office

This article presents the testimony before the Committee on the Environment and Public Works in the U.S. Senate about the EPA's effort to improve and make more consistent it's compliance and enforcement activities. Why GAO Did This Study The Environmental Protection Agency (EPA) enforces the nation’s environmental laws and regulations through its Office of Enforcement and Compliance ...

Jun. 28, 2006

By Environmental Data Management, LLC (EDM)

Climate Change, Various Adaptation Efforts are Underway at Key Natural Resource Management Agencies

This report examines (1) steps key federal natural resource management agencies—Forest Service, NOAA, Fish and Wildlife Service, National Park Service, and Bureau of Land Management—have taken since 2007 to address adaptation and (2) how these agencies have collaborated at the national level on adaptation since 2007. GAO analyzed the agencies’ climate change adaptation guidance ...

Jul. 8, 2013

By IWA Publishing

Effect of pH reduction on polyphosphate- and glycogen-accumulating organisms in enhanced biological phosphorus removal processes

We investigated the effect of pH reduction on polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) in the enhanced biological phosphorus removal (EBPR) process. Three laboratory-scale EBPR reactors were used. Initially, the reactors were operated at pH 7.9±0.1 and 6.5±0.1, and after 27 days, the pH was lowered to 6.5±0.1 and 6.0±0.1, respectively. PAOs and GAOs ...

Sep. 1, 2010

By IWA Publishing

Uncertainty and variability in enhanced biological phosphorus removal (EBPR) stoichiometry: consequences for process modelling and optimization

The overall potential for enhanced biological phosphorus removal (EBPR) in the activated sludge process is constrained by the availability of volatile fatty acids (VFAs). The efficiency with which polyphosphate accumulating organisms (PAOs) use these VFAs for P-removal, however, is determined by the stoichiometric ratios governing their anaerobic and aerobic metabolism. While changes in anaerobic ...

Apr. 1, 2010

By IWA Publishing

Integrating port and regional risk management strategies

In March, the Government Accountability Office (GAO) released Port Risk Management (GAO-07-412), which provided a series of findings on the challenges our nation’s port and maritime communities are experiencing with respect to all-hazards planning. The investigators of this report outlined “interagency coordination” as one of several challenges requiring remedy. Historically, the Department ...

Sep. 1, 2007

By ABS Consulting

Microbial community analysis involved in the aerobic/extended-idle process performing biological phosphorus removal

Recently, it has been found that biological phosphorus removal can be achieved in an aerobic/extended-idle (AEI) process using both glucose and acetate as the sole substrate. However, the microbial consortiums involved in glucose-fed and acetate-fed systems have not yet been characterized. Thus the aims of this paper were to investigate the diversities and dynamics of bacterial communities ...

Dec. 3, 2012

By IWA Publishing

Effects of injection of acetic acid and propionic acid for total phosphorus removal at high temperature in enhanced biological phosphorus removal process

In summer, wastewater treatment plant total phosphorus (TP) removal efficiency is low in South Korea. The reason is because of high temperatures or significant fluctuation of inflow characteristics caused by frequent rainfall. Hence, this study tried to raise TP removal efficiency by injecting fixed external carbon sources in real sewage. Polyphosphate accumulating organisms (PAOs) and glycogen ...

May 20, 2014

By IWA Publishing

Supply Concerns Continue, and Uncertainties Complicate Planning

The nation’s water bodies have long supplied Americans with abundant freshwater, but recent events, such as the ongoing California drought, have focused attention on competing demands for this limited resource. In the United States, the states are primarily responsible for managing freshwater resources, and many federal agencies influence states’ management decisions. In 2003, GAO ...

Jun. 9, 2014

By IWA Publishing

Simultaneous nitrification, denitrification and phosphorus removal (SNDPR) in a full-scale water reclamation plant located in warm climate

The combination of simultaneous nitrification-denitrification (SND) with enhanced biological phosphorus removal (EBPR) provides a more efficient and economically viable option for nutrient removal from municipal wastewater compared to conventional two-step nitrification-denitrification. This study analyzed the nutrients (N and P) profiles in a full-scale municipal wastewater reclamation plant ...

May 5, 2016

By IWA Publishing

The source of reducing power in the anaerobic metabolism of polyphosphate accumulating organisms (PAOs) – a mini-review

Glycolysis has been generally accepted to be the source of reducing power used for the synthesis of polyhydroxyalkanoates (PHAs) in the anaerobic metabolism of polyphosphate accumulating organisms (PAOs). However, the tricarboxylic acid cycle (TCA) has also been suggested to contribute to the generation of reducing equivalents, creating some controversy in this research field over the last two ...

Apr. 1, 2010

By IWA Publishing

Financial assurance and long-term stewardship

While financial reporting is a SEC requirement for all publicly traded companies, financial assurance is a requirement of regulatory authorities and applies to all responsible parties, whether publicly or privately held. Here the author tackles the question of the financial impact on companies if the scope of liabilities requiring financial assurance were increased and, as a result, they failed ...

Jul. 1, 2009

By AHC Group

Effect of Process Configurations and Alum Addition on EBPR in Membrane Bioreactors

ABSTRACTBench-scale studies were undertaken to explore the relative efficiency of three different process configurations for enhanced biological phosphorus (EBPR) removal; the University of Cape Town (UCT) process, the Sammamish Biological Nutrient Removal (SmBNR) process, and the University of Washington Membrane Biological Nutrient Removal (UW-MBNR) process. In this study, they all had the same ...

Oct. 22, 2006

By Water Environment Federation (WEF)