Presentation on theme: "Appeal of NSF/ANSI 60 Drinking Water Additives Treatment Chemicals Chlorate SPAC JOINT COMMITTEE - DRINKING WATER ADDITIVES, TREATMENT CHEMICALS MEETING."— Presentation transcript:
Appeal of NSF/ANSI 60 Drinking Water Additives Treatment Chemicals Chlorate SPAC JOINT COMMITTEE - DRINKING WATER ADDITIVES, TREATMENT CHEMICALS MEETING November 29, 2011 Dr. Susan Anderson Olin Chlor-Alkali
Background Olin is a voting member of the NSF Standard 60 Drinking Water Additives Treatment Chemicals Committee. Olin was a member of the NSF Standard 60 Perchlorate Task Group. Olin interests are directly and materially affected by the Chlorate Revision.
Timeline Ballot Issue 46, which pertained to the perchlorate levels in drinking water and drinking water additives, revision 2 was circulated to the Joint Committee in September and October 2010. The ballot successfully passed. After one conference call, the Perchlorate Task group then proposed to add requirements for an Maximum Contaminant Level (MCL) of 1ppm chlorate in drinking water and a SPAC of 0.2ppm as the hypochlorite contribution to the MCL. The first ballot was distributed March 11, 2011.
Procedural Issues of Concern The Perchlorate Task Group did not follow NSF/ANSI procedures before bringing the chlorate revision to a vote before the Joint Committee. The determination of chlorate residual is a very complex issue involving health, regulatory, chemical, measurement and process issues. The Perchlorate Task Group did weigh and evaluate all these issues associated with a perchlorate residual in sodium hypochlorite.
Procedural Issues of Concern (cont.) The Perchlorate Task Group discussion of the Chlorate residual in sodium hypochlorite consisted of one conference call at the very end of that task groups discussions. A robust and balanced discussion of chlorate did not occur. No consensus on the Chlorate Revision was reached by the Perchlorate Task Group and without a formal task group for chlorate, there was no appropriate forum of discussion and consensus on the complex issues posed by the Chlorate Revision.
Basis of Chlorate Revision There were many issues to discuss before setting a chlorate residual that justify a task groups attention. Chlorate Revision is based upon a report by Health Canada as the primary source of chlorate guidance. The data used to determine guideline is limited, non- conclusive and statistically insignificant.
Basis of Chlorate Revision (cont.) No regulation or legislation was submitted to support this guideline. The USEPA has only recently issued a proposal to start monitoring chlorate in order to determine whether or no a health advisory/regulation is necessary. Basing an NSF/ANSI requirement on limited data and disputed conclusions is premature.
SPAC Determination The Single Product Allowable Concentration (SPAC) calculations used to set the Maximum Use Level (MUL) are confusing and misleading. SPAC calculations for the MUL specify four sources: 1) source water, 2) hypochlorite, 3) chlorine dioxide and 4) an unknown. Based on four sources the SPAC should have been 0.25 times the MCL yet the SPAC was set at 0.2 times the MCL. The proposed SPAC would mislead users to think that there are five sources.
SPAC Determination (cont.) It would be more appropriate to specify only three sources of chlorate: 1) source water, 2) chlorination choice and 3) an unknown. The choice to use chlorine gas, sodium hypochlorite, or chlorine dioxide for disinfection is a mutually exclusive choice. The allowable residual level of chlorine does not change with the source of chlorination. Therefore, the SPAC should be based on 1/3 the drinking water level in contrast to the currently proposed 1/5 the drinking water level. Furthermore, if low chlorate sodium hypochlorite is desired then a low chlorate hypochlorite specification should e considered (similar to low bromate sodium hypochlorite).
Lack of Proper Forum Customer Issues There was no available forum for adequate discussion of the ramifications of the Chlorate Revision for Customers (Users). Sodium Hypochlorite can be manufactured, shipped and received by users that meets the standard. However, the onus will then be on the User to maintain that initial chlorate concentration. Chlorate is a degradation product in sodium hypochlorite. That degradation is highly dependent on storage conditions. This can result in significant costs to Users from both a capital cost and administrative standpoint. These changes were neither appreciated nor discussed by the Perchlorate task group.
Summary The NSF bypassed it own procedures by not allowing any reasonable forum to discuss the complex issues posed by the Chlorate Revision. To further highlight what appears to be a rush to decision, NSF presented the Chlorate Revision as part of a sodium hypochlorite presentation at the OTCO 49 th Annual Water Workshop, March 23, 2011 before the Chlorate Revision ballot had even been closed.
Summary ( cont. ) It is premature to adopt a Chlorate Revision when there was an insufficient forum to raise significant issues associated with limited data and questionable conclusions. Olin requests the Joint Committee form a chlorate specific task group to properly address the chlorate issue in compliance with NSF/ANSI protocols.