US Environmental Protection Agency Office Research Articles

A Comparison of Two Macroinvertebrate Multi-Plate Sampling Methods to Inform Great Lakes Monitoring and Remediation Efforts.

Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and restoration efforts at the Niagara River Great Lakes Area of Concern site, a multi-agency study was conducted in 2014 to assess the contribution of seven major urban tributaries on the US side of the river toward the impairment of the Niagara River. As part of this study, macroinvertebrate communities were sampled using two co-located versions of HD samplers: one version used by the New York State Department of Environmental Conservation (NYSDEC) and another by the US Environmental Protection Agency Office of Research and Development. Samplers were deployed in tributaries in highly developed watersheds with high percent impervious surface. The two sampling methods varied in terms of number and size of plates, between-plate spacing, and deployment method. Comparison of the similarity/grouping of communities with multivariate ordination techniques, Nonmetric Multidimensional Scaling and Multi-Response Permutation Procedure, showed that both methods were able to detect differences in communities at stations, despite some grouping by month and method. The indices and metrics derived from the two HD methods were found to give comparable but not identical assessments of water quality. Despite their differences, the methods were robust with respect to water quality categories derived from indices used nationally (HBI) and by NY state (BAP). For the common richness metrics, total taxa and EPT richness, there was no statistical difference between means from 3 samplings. Some metrics, especially percent tolerant collector-gatherer individuals, did show significant differences at certain stations. Indicator Species Analysis showed some taxa associated with each method. The observed community differences were thought mostly due to the difference in sampler deployment position.

Water Utilities Should Not Be Strangers to WIFIA

Thanks to the labors of my predecessor, Tom Curtis; other volunteer leaders; and sustained advocacy by AWWA members at the grassroots, the Water Infrastructure Finance and Innovation Act (WIFIA) became law in 2014. It has been a smashing success, yet drinking water utilities have been slower to participate in the program compared with utilities managing wastewater, combined sewer overflow (CSO), and water reuse projects. This trend seems to have been reversing itself lately, but there are still too many missed opportunities for drinking water funding through WIFIA loans. Drinking water systems will send in a letter of interest, but then drop out of the running for reasons still unclear. WIFIA is a federal credit program that provides long-term, low-cost loans with fixed interest rates to creditworthy utilities. The program offers an extended repayment term of up to 35 years from completion of construction (usually five more years), deferred interest, and “sculpted” rates to match revenues with utility expenditures over the life of the loan. Other features such as the “drawdown” and prepayment enhance its attractiveness. It is also a great deal for the taxpayer. The WIFIA portfolio of loans generates US$100 of infrastructure spending for every $1 appropriated to the program by Congress. WIFIA loans finance up to 49% of approved projects, thereby stimulating other investments from tax-exempt bonds, state revolving funds (SRFs), or private equity. In 2021 alone, WIFIA will be able to lend approximately $5 billion. WIFIA is managed by the US Environmental Protection Agency (USEPA), which has done an outstanding job with setting up this new finance program. To date, it has closed on 49 loans totaling $9.3 billion (as of April 2021) to finance systems serving 31 million Americans. Various projects are eligible for WIFIA funding (see www.epa.gov/wifia), including the usual suspects such as treatment, storage, consolidation, water security, energy efficiency, and many more. Basically, anything eligible under either the Clean Water Act or Safe Drinking Water Act SRFs is fair game if the applicant is a public water system. Further, WIFIA loans fund not only projects, but ongoing programs such as lead service line and distribution system replacements—two areas of particular interest to drinking water utilities. While WIFIA has yet to fund a land-based source water protection project at scale, there is no reason a utility could not fund protection of a headwaters forest or deployment of easements and management practices on agricultural lands to protect the utility's reservoir or other source water. USEPA's Office of Groundwater and Drinking Water has identified a 200-year average cycle for replacement of distribution lines in the water sector. While one does not automatically replace, say, a 100-year-old line, postponing renewal for two or three centuries is not an asset management model that utilities should practice. Utilities often pay for distribution line renewals from their operating revenue on a pay-as-you-go basis rather than using debt financing with the cost spread over multiple years. WIFIA offers a means of getting ahead of the curve and reducing risk for current and future generations. Funding wastewater, CSO, and reuse projects is important and will continue to be a big part of the WIFIA program, but it would be ironic if drinking water utilities did not take advantage of this marvelous program that AWWA labored so hard to create, fund, and protect over the past decade. WIFIA and drinking water utilities should not be strangers to each other. G. Tracy Mehan III is executive director of the AWWA Government Affairs Office in Washington, D.C. He can be reached at tmehan@awwa.org.

Vertical screening distances for total petroleum hydrocarbon for vapour intrusion risk assessment at petroleum underground storage tank sites

The US Environmental Protection Agency Office of Underground Storage Tanks (US EPA OUST) and Interstate Technology and Regulatory Council (ITRC) have recently published guidance indicating that buildings separated from light non-aqueous phase liquid (LNAPL) sources by more than 15 ft (4.6 m) are not a concern for vapour intrusion at petroleum underground storage tank (UST) sites. At this distance, there is a greater than 95% probability that soil gas concentrations for all key constituents of potential concern are below risk-based screening levels (RBSLs) between the LNAPL source and building foundation. Vertical screening distances for bulk Total Petroleum Hydrocarbon (TPH), common TPH fractions (C 5 –C 8 aliphatics, C 9 –C 12 aliphatics, and C 9 –C 10 aromatics), and indicator compounds ( n -hexane and naphthalene) are less certain, however, because of a general lack of empirical data and highly variable soil-gas RBSLs. This study addresses these gaps through a statistical analysis of hundreds of soil-gas samples collected above LNAPL sources at more than 30 petroleum UST release sites. Resulting vertical screening distances for the various TPH fractions range between 0 and 7 ft (2.1 m) depending primarily on soil-gas RBSLs, which vary by over 5 orders of magnitude. Vertical screening distances for naphthalene are generally <3 ft (0.91 m). Vertical screening distances for n -hexane range from 12 (3.7) to 16 ft (4.9 m) and vary geographically. Vertical screening distances for total (bulk) TPH generally exceed 15 ft (4.6 m). Petroleum vapour intrusion risk assessments involving total (bulk) TPH are not recommended, however, because of uncertainties in quantifying soil-gas and indoor-air concentrations and defining RBSLs for fuel mixtures with variable source composition, toxicity, and fate and transport properties. Overall, the findings of this study validate the 15-ft screening distance recommended by ITRC and US EPA for application at petroleum UST sites with LNAPL sources.

More for less: Analysis of the performance of avian acute oral guideline OECD 223 from empirical data.

Since the publication of the Organisation for Economic Co-operation and Development (OECD) avian acute oral guideline, OECD 223, empirical data have become available to compare the performance of OECD 223 with statistical simulations used to validate this guideline and with empirical data for US Environmental Protection Agency Office of Chemical Safety and Pollution Prevention (USEPA OCSPP) guideline OCSPP 850.2100. Empirical studies comprised 244 for Northern bobwhite, of which 73 were dose-response tests and 171 were limit tests. Of the dose-response tests, 26 were conducted to OECD 223 (using 3-4 stages) and 33 to OCSPP 850.2100 (using the single 50-bird design). Data were collected from 5 avian testing laboratories from studies performed between 2006 and 2013. The success with which the LD50 and slope could be determined was 100% and 96% for OECD 223 (mean 26 birds per test) and 100% and 51% for OCSPP 850.2100 (mean 50 birds per test). This was consistent with the statistical simulations. Control mortality across all species and designs amounted to 0.26% (n = 2655) with only single mortalities occurring in any 1 study and <1% for any 1 species. The simulations used to validate the OECD 223 design showed that control mortality up to 1% will have no observable impact on the performance. The distribution of time to death for Northern bobwhite, zebra finch, and canary were obtained from 90, 29, and 17 studies, and mortalities appeared within 3 d for 71%, 95%, and 91% of birds tested, respectively. Integr Environ Assess Manag 2017;13:906-914. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

An evaluation of fish early life stage tests for predicting reproductive and longer-term toxicity from plant protection product active substances.

The chronic toxicity of chemicals to fish is routinely assessed by using fish early life stage (ELS) test results. Fish full life cycle (FLC) tests are generally required only when toxicity, bioaccumulation, and persistence triggers are met or when there is a suspicion of potential endocrine-disrupting properties. This regulatory approach is based on a relationship between the results of fish ELS and FLC studies first established more than 35 yrs ago. Recently, this relationship has been challenged by some regulatory authorities, and it has been recommended that more substances should undergo FLC testing. In addition, a project proposal has been submitted to the Organisation for Economic Cooperation and Development (OECD) to develop a fish partial life cycle (PLC) test including a reproductive assessment. Both FLC and PLC tests are animal- and resource-intensive and technically challenging and should therefore be undertaken only if there is clear evidence that they are necessary for coming to a regulatory decision. The present study reports on an analysis of a database of paired fish ELS and FLC endpoints for plant protection product active substances from European Union draft assessment reports and the US Environmental Protection Agency Office of Pesticide Programs Pesticide Ecotoxicity Database. Analysis of this database shows a clear relationship between ELS and FLC responses, with similar median sensitivity across substances when no-observed-effect concentrations (NOECs) are compared. There was also no indication that classification of a substance as a mammalian reproductive toxicant leads to more sensitive effects in fish FLC tests than in ELS tests. Indeed, the response of the ELS tests was generally more sensitive than the most sensitive reproduction NOEC from a FLC test. This analysis indicates that current testing strategies and guidelines are fit for purpose and that there is no need for fish full or partial life cycle tests for most plant protection product active substances.

A Risk Assessment Framework for Waterborne Pathogens and Requirements for Producing a Complete Protocol

ABSTRACT The U.S. Environmental Protection Agency (USEPA), Office of Water, is developing a risk assessment protocol for determining microbiological pathogen risks in water (drinking, recreational, waste waters, etc.). This effort has been conducted in collaboration with the International Life Sciences Institute. A microbiological risk assessment framework was prepared and has been peer reviewed in the open literature and vetted at the USEPA and other federal government risk assessment venues. Some goals in development of the Framework were to make it comprehensive, easy to understand and to use, since it is recognized that improvements to the framework structure and instructional material would facilitate its use. The USEPA's Office of Water wishes to develop improved tools, methods, and approaches for conducting the analysis phase for risk assessments and would like to evaluate its efficacy for a broad range of waterborne pathogens in water/wastewater media. Improved understanding of microbiological survival, infectivity, and virulence factors is needed, especially at the genomic and proteomic levels to accurately assess the occurrence and fate of pathogens in water and to predict what intrinsic factors allow pathogens to be invasive and virulent. Development of improved dose-response models (including animal models) for pathogen exposures focusing on the dynamic circumstances of immunity, secondary spread, and sensitive subpopulations, would be useful additions to the Framework. In the future, USEPA may consider establishing comprehensive pathogen risk assessment guidelines that all its program offices can use.

Do bio‐based products move us toward sustainability? A look at three USEPA case studies

AbstractThe movement to buy “environmentally‐friendly” products was recently reinvigorated by the signing of the 2002 Farm Act that requires all federal agencies to give preference to products made, in whole or significant part, from biobased material. This paper addresses the reality behind widely held beliefs regarding “green” issues, and shows how complex it can be to choose among alternative products. Examples are presented in which the U.S. Environmental Protection Agency (USEPA) used diff e rent approaches, all based on life cycle assessment (LCA), to evaluate the environmental trade ‐offs of bio‐based alternatives. These examples incorporate various combinations of life cycle inventory (LCI) and life cycle impact assessment (LCIA).The first example presents results of a USEPA Office of Research &amp; Development (ORD) project called the Framework for Responsible Environmental Decision‐Making (FRED). The FRED framework uses a set of impact categories in an LCIA. Motor oil, wall insulation, and asphalt coating alternatives were all studied using FRED. The second example is a pilot study in the USEPA's Environmentally Preferable Purchasing program. Using a mix of LCI and LCIA, transformer oil and hard surface cleaner alternatives were evaluated. Finally, the paper presents preliminary LCI results of another ORD effort comparing fuel additives ethanol and MTBE. These examples demonstrate that the move to bio‐based products is not an across ‐ the ‐ board “win” for the environment. While LCAs cannot, at this time, provide a definitive answer as to the preferability of bio‐based products, it is the best tool to identify environmental tradeoffs, thereby providing additional information to support decision‐making.

Derivation of acute ecological risk criteria for chlorite in freshwater ecosystems

Chlorine dioxide has been proposed as an alternative to chlorine because it is a powerful disinfection agent that does not react with ammonia or chlorinated organics to form chloramines or trihalomethanes. The major reduction product formed when chlorine dioxide is added to water is the chlorite ion. Chlorite has been shown to be less toxic than free or combined chlorine. However, previous studies with eight freshwater families produced a US Environmental Protection Agency (USEPA) acute water quality criteria (WQC) lower than the WQC for chlorine. In the current study, an additional 12 families were added to the toxicological database to determine ecological risk criteria (ERC) using both the standard USEPA WQC methodology and the USEPA Office of Pesticide Programs (OPP) probabilistic approach. Chlorite LC50 values for the 20 family database ranged from 0.27 mg/L for the Daphnidae to 208.76 mg/L for the Salmonidae. The Daphnidae were by far the most sensitive family tested, with an LC50 44 times lower than the next most sensitive family tested, the Hyalellidae (LC50=1.19 mg/L) and 214 times lower than the most sensitive fish family tested, the Ictaluridae (LC50=5.79 mg/L). The Criteria Maximum Concentration calculated using the USEPA WQC methodology was 0.025 mg/L while the 95% ERC calculated using the USEPA OPP probabilistic methodology was 0.135 mg/L. The USEPA OPP probabilistic approach yields a criterion more consistent with the overall species sensitivity distribution and is not overly skewed by the low Daphnidae LC50 as is the USEPA WQC approach.

Comparison of Two U.S. Environmental Protection Agency Species Sensitivity Distribution Methods for Calculating Ecological Risk Criteria

Two major methods used by the U. S. Environmental Protection Agency (USEPA) to calculate ecological risk criteria using “species sensitivity distributions” (SSD) are compared using identical datasets. One method is the current USEPA Office of Water method for deriving acute numeric water quality criteria (EPA-FAV method). The 95% protection level generated by this method is the Final Acute Value (FAV). The other method is the USEPA Office of Pesticide Programs log normal distribution regression method that uses all available toxicological data in performing ecological risk assessments (OPP-Ecorisk method). Of the 50 comparisons made, 38% of the 95% protection levels calculated by the OPP-Ecorisk method are within a factor of 1.5 of the EPA FAV, 68% are within a factor of 2.0, 86% are within a factor of 2.5 and 92% are within a factor of 3.5. For pollutants where the difference between the OPP-Ecorisk 95% protection level and the EPA FAV are greatest, the OPP-Ecorisk 95% protection level is more protective than the EPA FAV. Where there are major differences, an analysis of the toxicity data indicates that the majority of the differences can be attributed to outliers, especially on the least sensitive ends of the toxicity distribution. In the one example dataset presented with one very sensitive genus, the OPP-Ecorisk method gave a protection level that was much closer to the lowest GMAV than the EPA-FAV method.

Interlaboratory validation of an atrazine immunoassay

An immunoassay method was validated in an interlaboratory study as an alternative test procedure to US Environmental Protection Agency (USEPA) method 508.1 rev. 2.0 for monitoring atrazine in drinking water in compliance with the Safe Drinking Water Act (SDWA). The study plan was approved by the USEPA Office of Water (OW). Nineteen laboratories participated in the study. Participants included personnel from water treatment plants and private and government laboratories certified to perform SDWA compliance monitoring. Field samples and reagent water were fortified with atrazine and shipped to study participants in a blind fashion. Data were used to generate quality control criteria to provide guidance for laboratories to evaluate method performance. The results of the study have been submitted to the USEPA OW for approval and promulgation of the method. This is the first immunoassay method to be validated under the SDWA.

Fundamentals, methods and future trends of environmental microwave sample preparation

Microwave (MW) sample preparation has nowadays become a standard analytical tool. A large section of MW systems, such as open vessel and low to high pressure closed vessel device, are used. Theoretical and practical considerations in the development as well as implementation of MW sample preparation are presented, including methods for total implementation of MW sample preparation are presented, including methods for total decomposition and leaching of trace elements in common environmental samples, such as soil, sludge, sediments, oils, biological materials, water and waste water. In particular, the US Environmental Protection Agency Office of Solid Waste methods 3050B, 3051, 3052 are discussed. Supporting reference data and documentation are presented to demonstrate specific alternative capabilities. As a natural extension of this technique, MW-based devices were more recently used to heat solvents and sample matrices as a preparation tool for extraction of organic compounds. Since 1986 analysts have been using MW heating to extract various compounds from a variety of sample matrices. Information is provided about the development of an integrated MW solvent extraction technique and its capabilities, as well as perspective for extraction applications. The ASTM method D5765-95 on solvent extraction of TPH from soils and sediment as well as the draft of a new US EPA for Volatile Organic Compounds (VOCs) and Semi-Volatile Organic Compounds (SVOCs) from environmental samples are presented. The potential benefits are analogous to those achieved by sample decomposition, i.e. reduced reaction/extraction time, improved efficiency, reduced solvent consumption and better working environment.

Computers Bring Certification Exams to Operators

The Association of Boards of Certification (ABC), with a US Environmental Protection Agency Office of Drinking Water grant, is developing a computerized version of the Very Small Water System operator certification exam. The goal is to develop a computerized system for administering operator certification exams. Operators would take the test using their personal computer; this would save operators the trouble and expense of traveling to a central location to take the test.

Wilcher Seeks Shift to Pollution Prevention

Lajuana S. Wilcher was sworn in on Oct. 30, 1990, as US Environmental Protection Agency (USEPA) assistant administrator for water. Wilcher worked as an attorney with the agency from 1983 to 1986 and was a partner specializing in environmental law with a Washington, D.C., law firm at the time she was selected to head the USEPA Office of Water. J. B. McCraw, editor of AWWA's Washington Report newsletter, conducted this interview with Wilcher Dec. 18, 1990, at USEPA headquarters in Washington, D.C.

Regulating Lead: An Update

Jeanne Briskin is special assistant to Michael Cook, director of the US Environmental Protection Agency Office of Drinking Water. She directs a special task force developing regulations on lead in drinking water. After proposing a corrosion by‐products rule last August that called for a lead standard to be monitored at distribution system entry points and a treatment technique triggered by certain tap‐sample action levels, the agency recently indicated it is considering promulgating a final rule calling for a lead standard at the tap. J.B. McCraw, staff writer for the AWWA Washington Affairs Office, spoke with Briskin about this controversial topic during an interview conducted May 23 at agency headquarters in Washington, D.C.