Order in council: glycol guidelines

Glycol guidelines

P.C. 1994-106
January 20, 1994

Whereas, pursuant to section 53 of the Canadian Environmental Protection Act, the Minister of the Environment has established the annexed Glycol Guidelines;

Therefore, His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, pursuant to section 53 of the Canadian Environmental Protection Act, is pleased hereby to approve the annexed Glycol Guidelines, established by the Minister of the Environment.

Interpretation

1. In these guidelines,
"act" means the Canadian Environmental Protection Act; (loi)
"federal airport" means an airport that is:

1. owned or operated by the federal government, or
2. located on land that is owned by the federal government; (aéroport fédéral)

"glycol" includes ethylene, diethylene and propylene glycols; (glycol) "responsible federal department" means the federal department, board or agency that has the management or control of the land on which a federal airport is located; (ministère fédéral responsable)
"surface water" means any natural body of water frequented by fish; (eaux superficielles)
"fish" has the meaning assigned in section 2 of the Fisheries Act. (poisson)

Application

2. These guidelines apply in respect of federal airports.

Concentration

3. The responsible federal department should ensure that the discharge of glycols into surface water resulting from aircraft de-icing and anti-icing activities at a federal airport does not exceed a concentration of 100 milligrams/litres (mg/L).

Sampling method

4. The concentration of glycols is to be determined based on the average of two samples collected at least 30 minutes and no more than 24 hours apart just before the place of discharge of the glycols into surface water.

Analytical method

5. Samples are to be analysed in accordance with the "Method for the analysis of glycols in water", set out in the Schedule.

Monitoring and reporting

6. The responsible federal department should:

1. monitor or ensure the monitoring of glycol concentration at those federal airports approaching or exceeding the concentration limit
2. prepare in respect of each de-icing season a report on the results of the monitoring
3. make the report available on request on or before September 30 following the end of the de-icing season to which the report applies

Schedule

Method for the analysis of glycols in water

Ethylene glycol (EG), diethylene glycol (DEG) and propylene glycol (PG as 1,2 and 1,3 isomers) are the common glycols found in aircraft de-icing/anti-icing fluids (ADAFs). De-icing formulations used at federal airports contain these glycols at between 54 and 67 percent by weight. Based on these values, between 4700 and 5800 tonnes of ethylene glycol (EG), DEG and propylene glycol (PG) are used each year at federal airports.

Glycols have been analysed many ways. The most commonly used method for the analysis of high concentrations of glycols in water is direct injection of the water samples into a gas chromatograph (GC) equipped with a flame ionization detector (FID). This method is recommended by the American Society for Testing Materials (ASTM), for example, for the analysis of glycols in engine coolants. Variations of the ASTM method are currently used by a number of analytical groups.

I. Sample collection and preparation

Because glycols biodegrade, analyse the sample as soon as possible after collection. Collect the samples in amber vials leaving no headspace (40 mL vials provide sufficient sample). Seal samples with Teflon-lined caps and store at 4°C until analyzed. Conduct appropriate storage studies to determine sample stability and the need for the addition of preservatives. The department recommends that a procedure for the use of appropriate travel and laboratory blanks be established.

II. Suggested starting gas chromatograph-flame ionization detector (GC-FID) conditions

To achieve optimum detector sensitivity, a larger jet may have to be used with the flame ionization detector (FID). A guard column may extend the life of the analytical column.

III. Method performance specifications

Performance specifications for the analysis of glycols have not been completely developed. Interim performance criteria are as follows:

• Method detection limit: Method detection limit for the glycols of interest should be in the range of 5 to 10 mg/L.
• Accuracy: Analysis of water samples should give recoveries of blind standards in the range of 80 to 120% recovery. If an internal standard is used, its recovery should also be in the range of 80 to 120%. Note that, because the glycols are subject to rapid biodegration, lengthy. holding times adversely affect accuracy.
• Precision: Standard deviation between sample duplicates should be less than 20%.

IV. General considerations

Because glycol concentrations are expected to be relatively high, samples may have to be diluted before injection to achieve acceptable analytical results. If samples are extremely dirty, they may have to be filtered to remove suspended particles. An appropriate internal standard, such as butanediol or a similar compound, should be selected.

Aircraft de-icing/anti-icing fluids (ADAFs) are made up of other compounds in addition to glycols. Other possible contaminants include jet fuels and other agents which may be present as a result of airport operations. It is not expected that these compounds will pose problems in the analysis of glycols. However, their presence should be noted.

V. Final recommendation

Monitoring programs pursuant to section 6 of the Glycol Guidelines should, as appropriate, incorporate proper sampling, validation and quality assurance/quality control (QA/QC) of the analytical methods applied.