Aquatic Life Screening Value ALSV Methodology Assessment Proposed

US EPA is currently evaluating potential methods to derive “Aquatic Life Screening Value” ALSV, that could be used by EPA, States and Tribes to set water quality standards or used in ecological risk assessments. EPA has developed a set of draft white papers that explore: (1) the use of various tools to estimate aquatic toxicity data; (2) approaches for deriving community level benchmarks; and (3) procedures for better integrating plant effects data into community level assessments. A stakeholders meeting was held December 1, 2010, and the agency is accepting written comments on their proposed evaluation through January 15, 2011.

In order to characterize potential adverse effects of chemicals in the aquatic environment, the EPA, States an Tribes currently use available toxicity data from studies involving individual test species, which serve as surrogates for untested species. These data are collected for individual organisms exposed to chemicals and are then frequently extended to represent effects to populations of the same species, populations of similar genera/taxa, or to aquatic ecosystems. In many cases, the number of acceptable studies is very limited.

The goal of EPA’s current proposal is to examine how limited test results can best be used to characterize adverse effects on aquatic life, especially related to methods used by the Office of Pesticide Programs (OPP) and the Office of Water (OW). A portion of this work will address the derivation of an “Aquatic Life Screening Value” may be used to screen concentrations of pesticides and effluents in ambient waters. According to EPA, the ALSV might also be used by States and Tribes in the development of water quality standards.

EPA has proposed analyses to be conducted in order to determine the utility of specific methods to meet the mandates of the Clean Water Act (CWA) and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). After the analysis of available tools and methods, the agency’s conceptual approach will be to refine and finalize specific methods and considerations for deriving ALSVs for chemicals.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website

Comments On Vessel General Permit Requested

U.S. Environmental Protection Agency (EPA) has scheduled a session to request input on suggested improvements for the next Vessel General Permit (VGP). The VGP is a General National Pollutant Discharge Elimination System (NPDES) permit that regulates discharges incidental to the normal operation of certain vessels. EPA is seeking public comment on requirements currently contained in the 2008 VGP, which expires in 2013, and any changes or additions recommended for the next permit.

The listening session will be held on December 15, 2010 at EPA Headquarters, Washington, D.C. EPA will accept written comments and relevant information for developing the next permit until December 31, 2010.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website

ADEQ Proposed General Permit For Pesticide Application

The Arizona Department of Environmental Quality (ADEQ) released a proposed general permit applicable to point source discharges of pesticides to the waters of the State (Permit No. AZG2011-001). This permit applies to pesticide application on or near surface waters in Arizona. The draft permit includes numerous requirements to be completed before, during and after pesticide applications.

Read a summary of the proposed ADEQ general permit for application of pesticides


EPA requires all States that are authorized to issue NPDES permits, including Arizona, to issue permits for pesticide applications. Most States have elected to prepare a general permit format.

Link to additional information on pesticide application permits


Coverage under the draft general permit will be available for pesticide application operators. An operator generally includes both (1) the entity with control over the financing for, or the decision to perform pesticide applications and (2) the entity with day-to-day operational control of or who performs activities (e.g., the application of pesticides) that are necessary to ensure compliance with the permit. More than one operator may be responsible for compliance with this permit for any single discharge from the application of pesticides.

The permit will be available to operators who apply either biological pesticides or chemical pesticides, when the pesticide application falls within specified pesticide use patterns.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website

Annual Treatment Area Thresholds In Proposed ADEQ Pesticide Application Permit

In December 2010, the Arizona Department of Environmental Quality (ADEQ) released a proposed general permit applicable to point source discharges of pesticides to the waters of the State (Permit No. AZG2011-001). This permit applies to pesticide application on or near surface waters in Arizona.

Read a summary of the proposed ADEQ general permit for application of pesticides


Read background on pesticide permitting requirements


Operators required to submit an NOI that meet or exceed the annual threshold(s) must comply with the Integrated Pest Management (IPM) Practices listed in the permit. In addition, operators that exceed annual thresholds also prepare and implement a Pesticide Discharge Management Plan (PDMP).

The Annual Treatment Area Thresholds proposed by ADEQ in the draft permit are:

Mosquitoes and Other Flying Insect Pests: 640 acres of treatment area

Aquatic Weed and Algae Control:

In Water: 20 acres of treatment area

At Water’s Edge: 20 linear miles of treatment area at water’s edge

Aquatic Nuisance Animal Control:

In Water: 20 acres of treatment area

At Water’s Edge: 20 linear miles of treatment area at water’s edge

Forest Canopy Pest Control: 640 acres of treatment area

Discharges to impaired waters or Outstanding Arizona Waters: Any amount

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website

Texas TCEQ Ordered To Issue Backlogged NPDES Permits

Environmental Protection Agency (EPA) has requested the Texas Commission on Environmental Quality (TCEQ) take the necessary steps to reissue Clean Water Act discharge permits to sewage treatment plants and industrial facilities in Texas.

TCEQ has a significant number of draft Clean Water Act discharge permits that not been issued pending resolution of various concerns raised by EPA. Of the 80 discharge permits of concern, a large number of these draft permits have been delayed due to issues regarding the toxicity of the discharges. In some cases, EPA has expressed concern that expired permits continue to authorize toxic discharges.

To ensure that TCEQ’s and EPA’s legal requirements and program commitments continue to be met, EPA has requested that TCEQ issue the overdue discharge permits within six months.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website