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Meat and Poultry Products Plant Liquid Effluent Regulations (C.R.C., c. 818)

Regulations are current to 2024-05-28

SCHEDULE IV(Section 9)Test Procedure for 96 Hour Acute Lethality Static Test

  • 1 The applicable portions of APHAFootnote *, sections 801 and 810, shall be used as a basis for this test procedure with the following modifications:

    • Return to footnote *Refers to the publication Standard Methods for the Examination of Water and Wastewater, 14th Edition (1975), published jointly by the American Public Health Association, American Water Works Association and the Water Pollution Control Federation.

    • (a) rainbow trout (Salmo gairdneri Richardson) shall be used as the standard test organism for the test procedure;

    • (b) only healthy, standardized stocks of properly acclimated rainbow trout shall be used;

    • (c) for each acute lethality test, at least 10 fish shall be exposed to a representative portion of the composite sample for a period of 96 hours and an equal number of fish shall be exposed for the same period under identical conditions to water used for holding fish stocks (control fish);

    • (d) this test is invalid if greater than 10 per cent of the control fish die;

    • (e) for each gram of fish there shall be at least 1.5 litres of fresh test sample per 96-hour test;

    • (f) the minimum water depth in any test vessel shall be 10 cm;

    • (g) the test sample shall be aerated or oxygenated with only that amount of air or oxygen required to maintain a minimum dissolved oxygen level of 8 mg/l and aeration or oxygenation shall be minimized to reduce the stripping of volatile compounds or the oxidation of acutely lethal components in the test sample. A maximum of two hours aeration of the test sample is allowed prior to the commencement of the test;

    • (h) in any test, individual fish shall weigh between 0.5 and 10 grams and the weight of the largest fish shall not be more than twice the smallest;

    • (i) the test shall be conducted at 15° ± 1° Celsius;

    • (j) the number of dead fish in the treatment and control vessels shall be recorded at 1/4, 1/2, 1, 2, 4, 8, 24, 48, 72 and 96 hours;

    • (k) there shall be no direct adjustment of the pH or other chemical characteristics of the test sample;

    • (l) when transportation or storage of a composite sample is necessary, special precautions shall be used to minimize degradation as follows:

      • (i) the sample shall be kept in sealed containers which are completely filled to the exclusion of all air,

      • (ii) if it is necessary for the sample to be stored more than 60 hours between collection and testing, the sample shall be brought to a temperature range of 1° to 6 °C as soon as possible after collection and maintained at this temperature range until just prior to being tested, and

      • (iii) acute lethality testing shall commence as soon as possible but in no case shall it commence later than four days after sampling.


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