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Offshore Chemical Selection Guidelines
for Drilling & Production Activities on Frontier Lands
April 2009
Copyright/Permission to Reproduce
6.0 Records To Be Maintained and Reporting Requirements
| Figure 6-1 | Chemical Selection Flowchart |
| CAPP | Canadian Association of Petroleum Producers |
| Cefas | Centre for Environment, Fisheries and Aquaculture Science |
| CEPA | Canadian Environmental Protection Act |
| CHARM | Chemical Hazards and Risk Management |
| C-NLOPB | Canada–Newfoundland and Labrador Offshore Petroleum Board |
| CNSOPB | Canada–Nova Scotia Offshore Petroleum Board |
| DSL | Domestic Substances List |
| EEM | Environmental Effects Monitoring |
| EC50 | Median Effective Concentration required to induce a 50% effect |
| HOCNF | Harmonized Offshore Chemical Notification Format |
| MSDS | Material Safety Data Sheet |
| NEB | National Energy Board |
| NDSL | Non-Domestic Substances List |
| NSNR | New Substances Notification Regulations |
| OCNS | Offshore Chemical Notification Scheme |
| OCSG | Offshore Chemical Selection Guidelines |
| OSPAR | Oslo and Paris Commissions |
| PARCOM | Paris Commission (one of the two forerunners of OSPAR) |
| PCPA | Pest Control Products Act |
| PLONOR List | OSPAR Pose Little or No Risk to the Environment List |
| SNAc | Significant New Activity |
| UK | United Kingdom |
Definitions
| "Accord Acts" | means the Canada–Newfoundland Atlantic Accord Implementation Act, the Canada–Newfoundland and Labrador Atlantic Accord Implementation (Newfoundland and Labrador) Act, the Canada–Nova Scotia Offshore Petroleum Resources Accord Implementation Act, and the Canada–Nova Scotia Offshore Petroleum Resources Accord Implementation (Nova Scotia) Act. |
| "Board" | means the Canada–Newfoundland and Labrador Offshore Petroleum Board, the Canada–Nova Scotia Offshore Petroleum Board or the National Energy Board. |
| "Chemical" | in these Guidelines, chemical means a single, pure chemical or a product or formulation containing a number of different chemicals. |
| "Discharge" | in these Guidelines, discharge means a planned release of waste into the marine environment, which is approved by the Board, and is related to routine operational activity. |
| "Installation" | has the same meaning as in subsection 2(1) of the Canada Oil and Gas Installations Regulations, subsection 2(1) of the Nova Scotia Offshore Petroleum Installations Regulations, and subsection 2(1) of the Newfoundland Offshore Petroleum Installations Regulations. |
| "Operator" | means a person that holds
|
| "Pest control product" | has the same meaning as in the Pest Control Products Act (2002, c. 28). |
The Offshore Chemical Selection Guidelines (OCSG) provide a framework for chemical selection which minimizes the potential for environmental impacts from the discharge of chemicals used in offshore drilling and production operations. These Guidelines are applicable to the offshore areas under the jurisdictions of the National Energy Board (NEB), the Canada–Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB) and the Canada–Nova Scotia Offshore Petroleum Board (CNSOPB). These Guidelines were prepared jointly by the three regulatory Boards with the assistance of a government/industry/public working group established for this purpose. A listing of the membership of the working group is provided in Appendix 3.
The regulatory frameworks applicable to oil and gas activities in each of Canada's offshore areas are substantially the same. In the Newfoundland and Labrador offshore area, such activities are regulated by the C-NLOPB under the Canada–Newfoundland Atlantic Accord Implementation Act, S.C. 1987, c. 3 and the Canada–Newfoundland and Labrador Atlantic Accord Implementation (Newfoundland and Labrador) Act, R.S.N. 1990, c. C-2. In the Nova Scotia offshore area, oil and gas activities are regulated by the CNSOPB under the Canada–Nova Scotia Offshore Petroleum Resources Accord Implementation Act, S.C. 1988, c. 28 and the Canada–Nova Scotia Offshore Petroleum Resources Accord Implementation (Nova Scotia) Act, S.N.S. 1987, c. 3. The NEB is responsible for regulating oil and gas operations in the rest of Canada's offshore areas under the Canada Oil and Gas Operations Act, R.S.C. 1987, c. O-7.
Regulations governing drilling and production operations have been promulgated under each Act which contain requirements related to environmental protection. These Guidelines outline the minimum requirements associated with the selection of chemicals for use in offshore drilling and production operations.
These Guidelines will be formally reviewed every five years to ensure that they continue to reflect significant gains in scientific and technical knowledge. More frequent reviews may be initiated should the results of environmental effects monitoring programs or research studies indicate a higher than anticipated risk to the environment from chemicals which were selected in accordance with these Guidelines. Other reviews may be considered as the result of specific written requests to the Boards from government departments, industry, or the public.
The use of these Guidelines does not exonerate operators from their duty to meet legislation or regulatory requirements, including requirements of relevant authorizations and approvals.
These Guidelines provide a framework for the selection of drilling and production chemicals intended for use and possible discharge into the offshore areas under the jurisdiction of the Board. The objectives of these Guidelines promote the selection of lower toxicity chemicals to minimize the potential environmental impact of a discharge where technically feasible.
These Guidelines do not address the following:
In areas where increased risk to the environment has been identified, variations to the selection process described in these Guidelines may be required.
Legislation requires that an operator who proposes to carry on any work or activity related to oil or gas exploration or production must first obtain an authorization from the appropriate Board. In an application for an authorization an Operator should demonstrate that they have a chemical selection process incorporated into their management system that meets the minimum expectations outlined in these Guidelines. The Board may conduct periodic audits to ensure compliance with these Guidelines, and operator specific chemical selection systems.
The selection criteria in these Guidelines are intended to apply to the original chemical and transformation products where they are known.
Once a chemical has been chosen, the quantity used and its ultimate fate should be tracked. Its "ultimate fate" could include such aspects as storage, discharge overboard, waste brought to shore, injected downhole or being left in the well, or it could be consumed in a chemical reaction. This "material balance" will be calculated, where reasonably practical, using conservative assumptions if precise information is not readily available (i.e. assume any material otherwise not accounted for is discharged).
When a chemical is proposed for use in drilling or production operations, the OCSG should be used to determine the overall acceptability of the candidate chemical from an environmental perspective.
Collect information on the quantity, intended use and ultimate fate.
The Pest Control Products Act (PCPA) governs the importation, sale and use of pest control products, including products used as biocides in the offshore. All products to be used as a pest control product must be registered in accordance with that Act and used in accordance with label instructions.
For clarification, some products may contain chemicals that are known to have pesticide like properties or may be the same chemicals as in registered pest control products; however they do not necessarily require registration under the PCPA. Only those chemicals which are intended to be used as pesticides (biocides) require PCPA registration. In cases of uncertainty, the local Pest Management Regulatory Agency offices should be contacted. For contact information, see Appendix 1.
The Canadian Environmental Protection Act (CEPA) provides for the notification and control of certain manufactured and imported substances. The Domestic Substances List (DSL) is a list of substances approved for use in Canada.
Any substance that is not on the DSL is required to go through the New Substances Notification process. A new substance is assessed, and may have restrictions, controls or prohibitions imposed.
Schedule 1 of CEPA is a list of substances that are considered toxic. Substances determined to be "toxic" may have risk management strategies or may be proposed for "virtual elimination" under CEPA.
For chemicals already in use, verification of whether they have been added to the List of Toxic Substances should be conducted regularly.
Determine whether a discharge of the chemical is intended. If there is a discharge, the subsequent steps apply to chemicals which are discharged to the marine environment.
It should be noted that all discharges are subject to Board approval. These guidelines do not provide for authorization of any discharges.
The PLONOR List, generally agreed upon by OSPAR countries, contains a list of substances that will pose little or no risk to the environment.
The Centre for Environment, Fisheries and Aquaculture Science (Cefas), on behalf of the UK government, assigns product ratings for the petroleum industry based on the Offshore Chemical Notification Scheme (OCNS). These ratings are based on the physical, chemical and ecotoxicological properties of products. Cefas publishes a list of ranked products and their hazard classifications (see Appendix 2). The assigned hazard groups vary from category A (most hazardous) through E (least hazardous), and hazard quotient colour bands from purple (most hazardous), through orange, blue, white, and silver, to gold (least hazardous).
Operators should select chemicals with the least environmental risk where appropriate.
Although there are several toxicity tests available, the Microtox test has been selected as an initial screening test for these Guidelines. The Microtox test is one of the most widely accepted toxicity tests, and provides a rapid and cost effective method to evaluate the potential toxicity of production and/or drilling chemicals. Hydrocarbons are relatively toxic to the Microtox bioassay but could have little effect on other bioassays such as rainbow trout. Biological Test Method: Toxicity Test Using Luminescent Bacteria. Report EPS 1/RM/24 has been selected as the preferred screening protocol for these Guidelines. In the test mixture, the concentration of the chemical must be the same as the intended discharge concentration.
The following Microtox values should be used to determine the toxicity of a chemical formulation:
| EC-50(15) ≤ 75% > 75% |
Toxicity Toxic (fails test) Non-toxic (passes test) |
Although the chemical passes the Microtox test, a discharge and time limit as defined below should be imposed to reduce any potential adverse environmental effects which would not be predicted because the test is not universally applied. A chemical which passes this test should not be discharged in quantities greater than 10 tonnes per year per installation and for periods greater than two years without a Hazard Assessment (Step 9).
If the preceding steps do not enable the operator to determine the acceptability of a given chemical, the operator may conduct a chemical specific hazard assessment of the candidate chemical to determine its suitability for use.
The hazard assessment process should be documented and conducted in accordance with the UK OCNS models outlined in Appendix 2. If the OCNS models are not used, an equivalent methodology and criteria should be used to demonstrate to the appropriate Board that the objectives of these Guidelines have been met.
The OCNS (or equivalent) rating may be re-assessed with the application of site specific information before applying the decision criteria.
If there is no alternative to discharging an A or B chemical, or a colour band purple, orange, blue or white chemical, develop and provide justification that demonstrates to the Board how the discharge of the chemical will meet the objective of the Guidelines
Operators shall keep records of the steps used to evaluate prospective chemicals. These records may be audited by the Board.
Operators shall prepare and submit annually, a report that outlines each chemical used in the past year, including the hazard rating, quantity used, and its ultimate fate.
Figure 6-1: Chemical Selection Flowchart

Disclaimer: The information provided in this appendix was current as of the publication date of these Guidelines.
This appendix will provide initial guidance for the completion of a hazard assessment if the screening of the chemical is directed towards Step 9 of these Guidelines. The results and methodology of this assessment must be made available to the appropriate Board for audit purposes upon request.
The following is a brief description of the Harmonized Offshore Chemical Notification Format (HOCNF) required to complete a Cefas OCNS rating.
The hazard assessment should include information on the composition, fate and toxicity of the chemical in question. Under composition, the following information should be provided:
The following information should be considered in determining the fate of a chemical:
To determine a chemical's toxicity, the relevant toxicity for the following organisms should be evaluated:
As a minimum the data generated above should include details on the analytical protocols followed and should include laboratory quality assurance/quality control information.
The interpretation of the above test data will follow the OSPAR Convention models used for OCNS ratings to develop:
The CHARM or CHARM equivalent HQ can be re-assessed to generate a Risk Quotient (RQ) if installation-specific information is available, such as flow and discharge rates, and characteristics of the discharge dispersion plume.
The following tables describe the toxicity and HQ values associated with the OCNS ratings:
Table 1: The OCNS HQ and colour bands[1]
| Initial OCNS grouping | Result for aquatic toxicity (mg/l) |
Result for sediment toxicity (mg/l) |
|---|---|---|
| A | <1 | <10 |
| B | >1 - 10 | >10 - 100 |
| C | >10 - 100 | >100 - 1,000 |
| D | >100 - 1,000 | >1,000 - 10,000 |
| E | >1,000 | >10,000 |
| [2] Centre for Environment, Fisheries & Aquaculture Science (Cefas) | ||
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Table 2: The OCNS letter grouping[2]
These letter groupings are adjusted based on biodegration and bioaccumulation of the chemical. Adjustment of grouping is made according to Table 3.
Table 3: The OCNS letter grouping Adjustment[3]
| Increase by 2 Groups e.g. From C to E | Increase by 1 Group e.g. From C to D | Do not adjust initial grouping | Decrease by 1 Group e.g. From C to B | Decrease by 2 Groups e.g. From C to A |
|---|---|---|---|---|
| Substance is readily biodegradable and is non-bioaccumulative | Substance is inherently biodegradable and is non-bioaccumulative | Substance is not biodegradable and is non-bioaccumulative Or Substance is readily biodegradable and bioaccumulates |
Substance is inherently biodegradable and bioaccumulates | Substance does not biodegrade and bioaccumulates |
| [3] Guidelines To UK Offshore Chemical Notification Scheme Including The Classification Of Chemicals That Cannot Be Ranked By The Charm Model. July 2006. Prepared by: Cefas, Burnham-on-Crouch, Essex. | ||||
Chemicals screened using the risk assessment process are rejected or accepted depending on whether the assigned OCNS or equivalent rating is acceptable for use, as defined in Step 9 of these Guidelines.
Regulatory Members
Canada–Newfoundland and Labrador Offshore Petroleum Board
Canada–Nova Scotia Offshore Petroleum Board
Environment Canada
Fisheries and Oceans Canada
Indian and Northern Affairs Canada
National Energy Board
Natural Resources Canada
CAPP Industry Representatives
ExxonMobil
Husky Energy
Petro-Canada
Non-Government Organizations
Inuvialuit Game Council Natural
History Society of Newfoundland and Labrador