Environment Canada’s Response to the Proposal to Add Naphthenic Acids to the National Pollutant Release Inventory

A. Status Update (July 2014)
B. Original Response (December 2012)


A. Status Update (July 2014)

The December 2012 response to this proposal (see below) indicated that two information items were needed before continuing the established process to consider whether to add naphthenic acid fraction compounds to the list of National Pollutant Release Inventory (NPRI) substances. The first item is now available, while the second item is not yet available.

  1. The proceedings of the Naphthenic Acid Strategies Workshop (Saskatoon, November 24-25, 2011) were expected to include consistent terminology for the group of substances of interest, and to establish a precise description of this group of substances. The workshop proceedings were published in August 2013 (Headley et al., 2013). Workshop participants agreed on terminology for the group of substances of concern (“oil sands naphthenic acids” or “naphthenic acid fraction compounds”) and on a description of what substances are included in the group (as originally described in Headley et al., 2011). Previously, Environment Canada decided to proceed with consideration of this larger group of substances, rather than only those included in CAS RN 1338-24-5 as originally proposed (see below for the rationale for this decision). As expected, the workshop proceedings confirmed that the group of substances that are of concern are naphthenic acid fraction compounds.
  2. The results of an inter-laboratory study were expected to describe the best analytical methods for measuring these compounds. The results of this study would assist industry with determining how to estimate their releases of this complex mixture of substances, should naphthenic acid fraction compounds be added to the NPRI in the future. The results of the inter-laboratory study on analytical methods are not yet available.

Environment Canada intends to resume stakeholder consultations on the possible addition of naphthenic acid fraction compounds to the NPRI when the results of the inter-laboratory study become available.

References

J. V. Headley, M. P. Barrow, K. M. Peru and P. J. Derrick (2011): Salting-out effects on the characterization of naphthenic acids from Athabasca oil sands using electrospray ionization, Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering, 46, 844-854.

J. V. Headley, K. M. Peru, M. H. Mohamed, R. A. Frank, J. W. Martin, R. R.O. Hazewinkel, D.

Humphries, N. P. Gurprasad, L. M. Hewitt, D. C.G. Muir, D. Lindeman, R. Strub, R. F. Young, D. M. Grewer, R. M. Whittal, P. M. Fedorak, D. A. Birkholz, R. Hindle, R. Reisdorph, X. Wang, K. L. Kasperski, C. Hamilton, M. Woudneh, G. Wang, B. Loescher, A. Farwell, D. G. Dixon, M. Ross, A. Dos Santos Pereira, E. King, M. P. Barrow, B. Fahlman, J. Bailey, D. W. Mcmartin, C. H. Borchers, C. H. Ryan, N. S. Toor, H. M. Gillis, L. Zuin, G. Bickerton, M. Mcmaster, E.

Sverko, D. Shang, L. D. Wilson and F. J. Wrona (2013): Chemical fingerprinting of naphthenic acids and oil sands process waters – A review of analytical methods for environmental samples, Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering, 48:10, 1145-1163.


B. Original Environment Canada Response, December 2012

1. Introduction

On November 11, 2010, Environmental Defence submitted a proposal to add naphthenic acids (CAS RN 1338-24-5) to the National Pollutant Release Inventory (NPRI) starting with the 2012 reporting year.

While naphthenic acids (NAs) are present in all crude oils and bitumen, and have a number of industrial and commercial applications, Environmental Defence is primarily concerned with releases of NAs related to oil sands development. Oil sands facilities report on a range of NPRI substances released to and from tailings ponds. However, NAs are not currently listed as an NPRI substance, and facilities are not required to report NAs. Environmental Defence’s rationale for the addition, as identified in the proposal, is that NAs have been identified as a key source of toxicity in oil sands tailings and it is therefore important that information on this group of substances be publicly available.

2. Recommendations of the NPRI Multi-Stakeholder Work Group

As part of the established process for modifying the NPRIFootnote1 the Environmental Defence proposal to add NAs to the NPRI was referred to the NPRI Multi-Stakeholder Work Group (WG) for discussion and recommendations. The WG’s recommendations on the proposal are available on the NPRI website.Footnote2

3. On-Going Work on Naphthenic Acids

Work is on-going within the scientific community to develop (1) consistent terminology for the group of substances of interest, (2) to establish a precise description of this group of substances, and (3) to determine the best analytical methods for measuring these compounds.

An international workshop on “Analytical Strategies for Naphthenic Acids (NAs)” was held by Environment Canada on November 24-25, 2011. Workshop participants discussed developing consistent terminology and analytical methods for NAs. An inter-laboratory study was recommended to follow the workshop. The inter-laboratory study was organized and led by Environment Canada. A manuscript on the workshop and the inter-laboratory study has been prepared and will be submitted to the Journal of Environmental Science and Health, Part A. Pending the outcome of the external review process, the manuscript is expected to be published during 2013. The results of the workshop and inter-laboratory study are expected to provide the information that Environment Canada needs to move forward with the process for making a decision on whether to add NAs to the NPRI.

It should be noted that NAs with the CAS RN 1338-24-5 met the criteria of the Chemicals Management Plan categorization process, which was completed in 2006 as a requirement of the Canadian Environmental Protection Act, 1999(CEPA 1999) to identify which chemicals required further action. A risk assessment on NAs will be completed in the future (2016-2020) by Environment Canada and Health Canada, to determine whether this substance meets the criteria of toxic under section 64 of CEPA 1999. Information resulting from the risk assessment will therefore not be available in time to inform a decision on the current proposal to add NAs to the NPRI.

4. Environment Canada’s Response

Environment Canada understands that Environmental Defence would like data on NAs that may be released, disposed of, or recycled during industrial processes, including the extraction of bitumen from the oil sands. Although Environmental Defence has identified NAs with CAS RN 1338-24-5 as capturing this information, Environment Canada does not agree with this. The group of NAs with CAS RN 1338-24-5 is limited to commercial mixtures of NAs used as solvents, detergents and rubber reclaiming agents. These mixtures represent less than half of NAs found in bitumen and crude oil. Accordingly, Environment Canada will examine the addition of naphthenic acid fraction compounds (NAFCs) to the NPRI, since this is a larger group of NAs, and information on the larger group of substances is expected to satisfy the information request.

The ongoing work described in Section 3 above is expected to fill a significant information gap that currently exists regarding a precise description for NAFCs. Without this information, it is Environment Canada’s view that a decision cannot be made on whether to add NAs to the NPRI. The WG recommendations support this view. Accordingly, Environment Canada will continue the established process for modifying the NPRIFootnote1 once this information is available. The earliest that this information is expected to be available is 2013.

4.1 Rationale

4.1.1 Substances

Environmental Defence proposed to add naphthenic acids (CAS RN 1338-24-5) to the NPRI for the purpose of capturing comprehensive data on toxic substances in oil sands tailings. Environment Canada has decided that NAs with this specific CAS RN is not the appropriate substance listing to capture the data requested in the proposal. Therefore, Environment Canada will consider the addition of naphthenic acid fraction compounds (with no specific CAS RN) instead, based on the following rationale.

CAS RN 1338-24-5 specifically refers to commercial NA mixtures, which are used as solvents, detergents and rubber reclaiming agents. However, NA mixtures with CAS RN 1338-24-5 contain less than half of the NAs found in bitumen and crude oil. Using CAS RN 1338-24-5 would therefore limit the data to commercially used NAs. It would not capture comprehensive data on NAs that may be released, disposed of or recycled during industrial processes, including the extraction of bitumen from oil sands, and would therefore not satisfy the stated intent of the proposal.

The term “naphthenic acids” is not always used to represent the same group of substances. The term is usually used to represent a broader group of substances known as “acid extractable organics” or “naphthenic acid fraction compounds” (NAFCs). In addition, there is no current consensus on a precise description of NAs or NAFCs. In order to collect useful data on NAs from industry, a clear description of the group of substances on which reporting is required must be available. A precise description is not currently available, but is expected to become available as a result of the on-going work described above.

Environment Canada’s position is supported by the recommendations of the WG. The WG was not able to reach a consensus recommendation on the issue of which group of substances to consider for addition to the NPRI. However, some members of the WG felt that any possible listing of this group of substances should not be limited to the CAS RN 1338-24-5 (Recommendation 2.2).

4.1.2 Timing

Environmental Defence proposed to add NAs to the NPRI starting with the 2012 reporting year. Environment Canada will not be in a position to fully consider this proposal until a precise description for NAFCs is available (Section 3 above). This description is expected to become available during 2013. This position is also supported by the following recommendations of the WG:

  1. The WG recommendation that “… a decision on addition of this substance should be deferred until more information is known” (Recommendation 2.3); and
  2. The WG recommendation that “…NAs should not be added to the NPRI for the 2012 reporting year.” This will allow time for additional work to be completed on issues identified with the proposal (Recommendation 2.6).

Environment Canada will continue to consider Environmental Defence’s proposal once the description of NAFCs is available. The information from the workshop and inter-laboratory studies will be used for further stakeholder consultations on the proposal during 2013.


Footnotes

Footnote 1

See Modifying the National Pollutant Release Inventory: A Guide to the Procedures to Follow When Submitting Proposals and A Description of the Stakeholder Consultation Process.

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Footnote 2

See Proposal to Add Naphthenic Acids to the NPRI for the 2012 Reporting Year – Recommendations of the NPRI Multi-Stakeholder WG.

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