AMSA Regulatory Alert (RA 04-08)

To: Members & Affiliates
From: National Office
Date: April 14, 2004
Subject: EPA PROPOSES NEW CLEAN WATER ACT TEST METHODS, INCLUDING MERCURY 245.7
Reference: RA 04-08

Action Please By:
May 17, 2004

AMSA has advocated for over six years that the U.S. Environmental Protection Agency (EPA or the Agency) approve Method 245.7 for the analysis of mercury in wastewater. Finally, on April 6, 2004, the Agency proposed to approve a long list of new and updated test procedures for the analysis of pollutants under the Clean Water Act (CWA) (69 Fed. Reg. 18166), including Method 245.7. Regulated and regulatory entities alike use these EPA-approved methods for determining compliance with National Pollutant Discharge Elimination System (NPDES) permits or other monitoring requirements. The proposal would introduce new technologies to the NPDES program, update versions of previously approved methods, and remove certain outdated methods.

The proposed rule attempts to promote consistency between wastewater and drinking water compliance monitoring programs by adopting the same versions of methods for both programs. In addition to proposing new test methods for a variety of pollutants regulated under the CWA, EPA’s notice also proposes new sampling, sample preservation, and holding time requirements for NPDES compliance monitoring.

The Agency is seeking comments on the proposed rule until June 7, 2004. To facilitate the Association’s comment effort, please submit any comments to Will Pettit, AMSA’s Regulatory Analyst, at wpettit@amsa-cleanwater.org by May 17, 2004. A summary of EPA’s April 6 proposal follows.

Summary of New Proposed Test Methods

Method 245.7
In line with AMSA input to EPA over the past six years, the Agency has completed its validation work and is proposing to approve Method 245.7, Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry (http://www.epa.gov/waterscience/methods/), for the analysis of mercury in wastewater. If approved, Method 245.7 will provide publicly owned treatment works (POTWs) with a cost-effective alternative for monitoring mercury in their influent and effluent. Currently, POTWs are encouraged to use Method 1631 for mercury detection, which is very costly as it involves ultra-clean sampling techniques and a gold trap – not required under Method 245.7. Utilities will be able to achieve similar detection levels at a fraction of the cost with the new proposed method. The Association originally requested that EPA validate and approve Method 245.7 in July 1998, but subsequently learned in early 2000 that due to budget cuts there would be no further efforts to validate the method. In light of EPA’s 2000 decision, AMSA sent the Agency a petition (http://www.amsa-cleanwater.org/private/legreg/outreach/3-3-00PettitiontoEPA.pdf) that same year that urged EPA to conduct a formal rulemaking process to validate and approve this new method. AMSA’s Mercury Workgroup’s six years of advocacy on this issue has yielded this key proposal.

Regarding Method 245.7, the Agency is soliciting comments on requirements for sample collection when using this method. In addition, EPA is requesting comments and data demonstrating whether the following footnote, which was promulgated on October 29, 2002, at 40 CFR Part 136, should or should not also be applied to Method 245.7:

Samples collected for the determination of trace level mercury (100 ng/L) using EPA Method 1631 must be collected in tightly-capped fluoropolymer or glass bottles and preserved with BrCl or HCl solution within 48 hours of sample collection. The time to preservation may be extended to 28 days if a sample is oxidized in the sample bottle. Samples collected for dissolved trace level mercury should be filtered in the laboratory. However, if circumstances prevent overnight shipment, samples should be filtered in a designated clean area in the field in accordance with procedures given in Method 1669. Samples that have been collected for determination of total or dissolved trace level mercury must be analyzed within 90 days of sample collection.

Other New Proposed Test Methods
In addition to Method 245.7, a number of other new methods were proposed, which are as follows:

• ASTM D6508, Dissolved Inorganic Anions by Capillary Ion Electrophoresis,
• QuikChem Method 10-204-00-1-X, Cyanide using MICRO DIST and flow injection analysis,
• Kelada-01, Automated Methods for Total Cyanide, Acid Dissociable Cyanide, and Thiocyanate,
• Method CP-86.07, Chlorinated Phenolics by In situ Acetylation and GC/MS,
• Standard 4500-Cl, Chlorine by Low Level Amperometry,
• ASTM D6888-03 Available Cyanide by Ligand Exchange-FIA,
• ASTM D 6919-03, Cations and Ammonium in by Ion Chromatography,
• Standard Method 4500-Cl-D. Chloride by Potentiometry,
• ASTM D512-89 Chloride by Ion Selective Electrode,
• Standard Method 4500-CN-F, Cyanide by Ion Selective Electrode,
• ASTM D2036-98 A, Cyanide by Ion Selective Electrode,
• Standard Method 4500-S2-G, Sulfide by Ion Selective Electrode,
• ASTM D4658-92, Sulfide by Ion Selective Electrode,
• Standard Method 4500-NO3-D, Nitrate by Ion Selective Electrode,
• Method D99-003, Free Chlorine by Color Comparison Test Strip,
• Method OIA-1677, DW Available Cyanide by Ligand Exchange—FIA,
• Radium-226 and 228 by Gamma Spectrometry, and
• EPA 327.0, Chlorine Dioxide by Colorimetry

Alternate Test Procedure for WET
The Agency also proposed an alternate test procedure to measure whole effluent toxicity (WET) – Microtox® 1010. EPA is soliciting comments on whether to approve this testing procedure which measures acute toxicity of aqueous test samples using bacteria as a “screening level” test (i.e., permit limits would not be based on the test) for freshwater and marine discharges, and as a “definitive test” (i.e., would be used for compliance determinations) for marine and estuarine waters. Since the test organism is a saltwater bacterium, EPA seeks comment on whether it is appropriate for freshwater. A copy of Microtox® 1010 is available in the docket for this proposed rule (http://www.epa.gov/edocket, using the Docket ID No. OW-2003-0070).

1995 Test Methods Proposed for Comment
The Agency is also proposing a group of methods that were originally proposed for approval on October 18, 1995 (60 Fed. Reg. 53987), but were never approved. EPA is proposing these methods again, rather than finalizing them, because over eight years have passed, bringing a significant quantity of new information on the effectiveness of these methods.

These methods are:

• Method 200.2, Total Recoverable Elements Digestion,
• Method 200.8, Metals by Inductively Coupled Plasma-Mass Spectrometry,
• Method 200.9, Metals by Stabilized Temperature Graphite Furnace Atomic Absorption,
• Method 218.6, Hexavalent Chromium by Ion Chromatography,
• Method 300.0, Inorganic Anions by Ion Chromatography,
• Method 353.2, Nitrate and Nitrite by Colorimetry, and
• Revisions to Methods 180.1, 200.7, 245.1, 335.4, 350.1, 351.2, 353.2, 365.1, 375.2, 410.4, and 420.4.

The American Standard Test Method (ASTM) and Standard Methods versions of many of these methods were also proposed for approval.

Summary of Updated Test Methods
EPA’s proposed rule seeks to approve hundreds of updated methods, and includes an errata sheet for the WET manuals. Most of the revisions to existing methods are either technical or editorial, intended to improve user-friendliness. All of the updated methods are listed in the Federal Register notice (http://www.epa.gov/fedrgstr/EPA-WATER/2004/April/Day-06/w6427.pdf) and are included in the public docket.

Summary of Withdrawn Test Methods
EPA proposes to delete liquid-liquid extraction (LLE) methods, including EPA Methods 612 and 625 and Standard Methods Method 6410 B, as approved procedures for 1,2-dichlorobenzene, 1,3-dichlorobenzene, and 1,4-dichlorobenzene (originally included in the October 18, 1995 proposal). While these compounds can be determined by these LLE methods, significant losses of these volatiles can occur using the prescribed sample collection procedures in the LLE methods, resulting in relatively low recovery of these compounds. These compounds are more accurately and precisely analyzed by EPA Method 624 or 1625B (an isotope-dilution method that compensates for evaporation losses).
EPA also proposes to withdraw approval for all oil and grease methods that use chlorofluorocarbon-113 (CFC-113; Freon-113) as an extraction solvent because CFC-113 is a Class I ozone-depleting substance (ODS). On May 14, 1999 (64 Fed. Reg. 26315), EPA approved Method 1664A as a replacement for Freon-based oil and grease methods to reduce dependency on CFC-113 (Method 1664A uses n-hexane as an extraction solvent). To further reduce reliance on ODSs, EPA proposes to withdraw EPA Method 413.1 and USGS Method I-4540-85 from use, and to specify that only n-hexane extraction solvent (as used in EPA Method 1664A) is approved with the remaining methods. The withdrawal and replacement would take effect on December 31, 2005. EPA also proposed to withdraw Syngenta Method AG-625 for monitoring atrazine in drinking water.

For more information on EPA’s proposed rule, please see http://www.epa.gov/fedrgstr/EPA-WATER/2004/April/Day-06/w6427.pdf. AMSA asks members to provide the Association with comments on any of the Agency’s proposals and requests that these comments be sent to Will Pettit, AMSA’s Regulatory Analyst, at wpettit@amsa-cleanwater.org by May 17, 2004. AMSA will offer supporting comments to the Agency on its proposal of Method 245.7 – a positive outcome to AMSA’s Mercury Workgroup’s six years of advocacy on the issue – and will provide additional comments on other proposals based on member input. If you have any questions, please contact Chris Hornback, AMSA’s Director of Regulatory Affairs, at 202/833-9106 or chornback@amsa-cleanwater.org.