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Posts Tagged ‘water’

Sample Containers & Preservation for Mercury Analysis in Waters

Tuesday, July 30th, 2013

By Tim Crowther, Regional Client Services Manager, ALS Environmental – Canada

**NOTE: The content in this article does not apply to ALS Environmental’s USA locations.**

On August 15, 2013, ALS Canada will begin supplying our clients with borosilicate glass containers with Teflon® lined caps for the collection of total and dissolved mercury in all water samples. Hydrochloric acid (HCl) preservative will also be supplied. Recent literature and ALS experimental test results indicate a glass container with HCl preservation is the most effective method for reducing mercury losses following sample collection. The sample bottle and preservative pictured overpage will be the recommended container for low-level total and dissolved mercury (≥10 ng/L), which were previously collected in a high-density polyethylene (HDPE) ‘plastic’ bottle with nitric acid preservation. HDPE containers are not suitable for ultra-trace level (0.2 – 10 ng/L) mercury analysis. Ultra-trace mercury sampling requires more sample volume, as well as the use of cleaner sample handling and analysis procedures.

The British Columbia Ministry of Environment (BC MoE) will require the use of Teflon® or borosilicate glass containers with HCl preservation for the collection of water samples for mercury analysis effective November 15, 2013. The United States Environmental Protection Agency (US EPA) and the Ontario Ministry of Environment have already prescribed the same. Various other agencies are considering similar changes, including the Canadian Council of Ministers of the Environment (CCME) and Alberta Environment.

Additionally, ALS recommends that filtration for dissolved mercury analysis be conducted within one hour of sample collection using a suitable in-line filter or 0.45 μm syringe filter supplied by ALS.

Read more about Sample Containers & Preservation for Mercury Analysis in Waters…

New and Revised Clean Water Act Methods Proposed

Thursday, September 23rd, 2010

New and Revised Clean Water Act Methods ProposedIn August 2010 the EPA issued a notice proposing new and revised analytical methods to be used under the Clean Water Act (CWA).

The proposed rule, entitled “Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act; Analysis and Sampling Procedures”, will affect numerous EPA Methods, ASTM Methods, Standard Methods, and alternative test methods.

EPA methods:

Read more about the proposed CWA Methods…

EPA Proposes New Permit Requirements for Pesticide Discharges

Wednesday, September 1st, 2010

New Permit Requirements for Pesticide Discharges

In June 2010, the U.S. Environmental Protection Agency (EPA) released a draft of its National Pollutant Discharge Elimination System (NPDES) permit. Through the permitting process, the EPA is seeking to decrease the amount of pesticides discharged into waterways. The new permit, also known as the Pesticides General Permit (PGP), was developed in response to a 2009 court decision, which ruled that pesticides can be classified as pollutants under the Clean Water Act.

The EPA’s PGP authorizes the controlled release of the following substances into U.S. waterways:

Read more about EPA’s Proposed New Permit Requirements for Pesticide Discharges…

Proposed NPDES Rule Requires ‘Sufficiently Sensitive’ Test Methods

Monday, August 2nd, 2010

Sufficiently Sensitive Test Methods

In a Federal Register notice published June 23, the EPA proposed changes to its permitting program under the Clean Water Act (CWA) to ensure the use of sufficiently sensitive analytical methods for monitoring chemical pollutants in discharge water.

Specifically, the new rule affects the CWA’s National Pollutant Discharge Elimination System (NPDES). Its purpose is to specify that applicants and permittees must use analytical methods that are capable of detecting and measuring pollutants at, or below, current water quality criteria.

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Deionized vs. Distilled Water

Monday, July 12th, 2010

By Gregory Salata, Ph.D., Kelso, WA

Deionized vs. Distilled Water

Many sampling programs include collection and analysis of an equipment blank to ensure there is no contribution of contaminants from the sampling equipment and associated process. To establish that sample collection procedures are contaminant free, an equipment blank is often collected. Equipment blanks are collected by passing water through the sample collection apparatus or utensil and collecting the water into the appropriate containers. To ensure that the water itself is contaminant free, the laboratory will supply the field crew with deionized (DI) water.

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How to Determine Aquatic Humic Substances

Monday, June 28th, 2010

By Lynda Huckestein, Project Chemist, Kelso, WA

How to Determine Aquatic Humic Substances

Aquatic Humic Substances (AHS) result from the decomposition of plant and animal residues and are found in soil, sediment, and water. They are widespread in nature and are mostly comprised from naturally occurring dissolved organic matter in water.

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USGS Study Finds Drinking Water Contaminated, but Safe to Drink

Tuesday, March 16th, 2010

Contaminated Drinking WaterA recent United States Geological Survey (USGS) study of public drinking water wells in California, Connecticut, Nebraska and Florida found that some were contaminated, but in amounts so minimal, human health was unlikely to be affected. The USGS tracked the movement of contaminants in groundwater and public-supply wells in four different aquifers.

According to the USGS, wells are not equally vulnerable to contamination because of differences in three factors: the general chemistry of the aquifer, groundwater age, and direct paths within aquifer systems that allow water and contaminants to reach a well. The importance of each factor differs among the various aquifer settings, depending upon natural geology and local aquifer conditions, as well as human activities related to land use and well construction and operation. However, the USGS feels that the study of the four different aquifer systems can be applied to similar aquifers and wells throughout the nation.

Read more about drinking water contamination…