Miss. Code. tit. 11, pt. 6, ch. 1, subch. 2, exh. 11-6-1-2-D to Chapter 1, Subchapters 1 and 2

Current through January 14, 2025

Exhibit 11-6-1-2-D to Chapter 1, Subchapters 1 and 2 - BIOASSAY REQUIREMENTS

I. Chronic Bioassay Requirements

The Water Quality Standards of Mississippi require that waters shall be free from substances attributable to municipal, industrial, agricultural, or other discharges in concentrations or combinations that are toxic or harmful to humans, animals, or aquatic life (State of Mississippi, Water Quality Criteria for Intrastate, and Coastal Waters, Section II.4., Minimum Conditions Applicable to All Waters (current edition). In accordance with such requirements, an NPDES permit holder is authorized to discharge from outfall(s) only in accordance with the following conditions:

1. The permittee shall submit any existing toxicity data for review by the Mississippi Office of Pollution Control within 30 days of the effective date of this permit.

2. The permittee shall perform 7-day chronic, static renewal, definitive (a control and five effluent concentrations) WET tests in accordance with Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Fresh water Organisms, (EPA/600/489/001) or Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, (EPA/600/4-87/028) or the most recent edition.

(a) Dilution water used for these tests shall consist of reagent grade water, defined as distilled or deionized water that does not contain substances which are toxic to the test organisms. For freshwater tests, dilution water shall consist of reagent grade chemicals or mineral water combined to make moderately hard dilution water according to Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA/600/4-89/001) or most recent edition⁹. For estuarine testing, dilution water shall consist of synthetic seawater or hyper-saline brine combined to achieve a salinity of 20 parts per thousand according to Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms (EPA/600/4-87/028) or most recent edition. These dilution waters will be deemed acceptable if the control organisms in the toxicity tests meet the minimum EPA criteria for chronic tests.

(b) If the Mississippi Office of Pollution Control determines the receiving waters are freshwater, the permittee shall conduct a Ceriodaphnia dubia Survival and Reproduction Test, and a Pimephales promelas Larval Survival and Growth Test on serial dilutions of effluent to determine if the discharge from outfall(s) is chronically toxic. Such testing will determine if the water affects the survival, growth, and reproduction of the test organisms. Static renewal tests will be conducted on three 24- hour composite samples of effluent. The first of these composite samples will be used to set up the tests and for the day 1 and day 2 renewals, the second of these composite samples will be used to renew the tests on days 3 and 4, and the third composite sample will be used to renew the tests on days 5 and 6. Not more than 36 hours will elapse between sampling and the first use of any of the composite samples. The chronic test(s) shall be considered valid only if the acceptability criteria referenced in Short-Term Methods for ⁹ Contact MDEQ Office of Pollution Control Laboratory for information on most recent editions(s) of methods manual Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, (EPA/600/4-89/001), or the most recent edition, are met. All data shall be statistically analyzed according to the referenced manual.

(c) If the Mississippi Office of Pollution Control determines that the receiving water is estuarine, the permittee shall conduct a Menidia beryllina Larval Survival and Growth Test and a Americamysis Survival, Growth, and Fecundity Test on serial dilutions of effluent to determine if the discharge from outfall(s) is chronically toxic. Such testing will determine if the water affects the survival, growth, and fecundity of the test organisms. Static renewal tests will be conducted on three 24-hour composite samples of effluent. The first of these composite samples will be used to set up the tests and for the day 1 and day 2 renewals, the second of these composite samples will be used to renew the tests on days 3 and 4, and the third composite sample will be used to renew the tests on days 5 and 6. Not more than 36 hours will elapse between sampling and the first use of any of the composite samples. The chronic test(s) shall be considered valid only if the acceptability criteria referenced in Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, (EPA/600/487/028) or most recent edition are met. All test data shall be statistically analyzed according to the referenced manual.

3. These chronic toxicity tests shall be initiated within 90 days of the date of issuance of the permit to evaluate wastewater toxicity. Such chronic toxicity tests shall be conducted once per quarter for a period of one year following the effective date of the permit. After the first year of monitoring, provided the IC₂₅ is greater than or equal to the IWC% the frequency of monitoring will be reduced to once per six months for the life of the permit. Sampling shall be timed to cover the seasonal extremes of the year (hot-dry and cold-wet).

4. If any one chronic toxicity test indicates the IC₂₅ is less than the IWC%, the provisions in Section 6 below shall apply, and the permittee shall conduct another chronic toxicity test(s) with the organism(s) that failed. This follow-up test must be completed within 30 days following completion of the failed test. Final chronic toxicity test results shall be in report form as outlined in Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. The permittee must also submit a completed Mississippi Office of Pollution Control NPDES Whole Effluent Toxicity Testing Report Form.

5. In the event the permittee passes the additional WET test, the permittee shall resume testing in accordance with the testing schedule set forth in the permit. In the event the permittee fails the second WET test, the permittee shall submit a Toxicity Reduction Evaluation Plan (TREP) within 45 days following completion of the follow-up test in order to reduce the toxicity of the effluent to safe ¹⁰ levels¹¹. The first phase of the TREP will include increased monitoring to characterize the toxicity of the effluent.

6. If the IC₂₅ of any test is less than the IWC%, then the effluent will be considered unacceptably chronically toxic, and this will constitute a violation of Part I of this permit.

7. In addition to the specific conditions of this permit, the permittee shall comply with all applicable conditions of 40 CFR 122.7 and 40 CFR 122.61 (06-03-93).

II. ACUTE BIOASSAY REQUIREMENTS

The Water Quality Standards of Mississippi require that all waters be free from substances in concentrations or combinations which are harmful to humans, animals, or aquatic life (State of Mississippi, Water Quality Criteria for Intrastate, Interstate and Coastal Waters (current edition). In accordance with such requirements, the permittee is authorized to discharge from outfall(s) only in accordance with the following conditions:

1. The permittee shall submit any existing toxicity data for review by the Mississippi Office of Pollution Control within 30 days of the effective date of this permit.

2. The permittee shall perform static renewal (tests that exceed 48 hours shall be renewed), definitive (a control and five effluent concentrations) toxicity tests at 25°C in accordance with Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or the most recent edition. Acute toxicity tests will be conducted on 24-hour composite samples of effluent, and tests must be initiated within 36-hours of completion of the sampling period.

(a) If the Mississippi Office of Pollution Control determines the receiving stream is freshwater, the permittee must use both the following test organisms and test durations:

(1)Pimephales promelas ([LESS THAN] 24-hrs.of age) - 96 hour

(2)Ceriodaphnia dubia - 48 hour

(b) If the Mississippi Office of Pollution Control determines the receiving stream is marine or estuarine, the permittee must use both the following test organisms and test durations:

(1)Menidia beryllina - 96 hour

(2)Americamysis - 48 hour

(c)Dilution water used for these tests shall consist of reagent grade water, defined as distilled or deionized water that does not contain substances which are toxic to the test organisms. For freshwater tests, dilution water shall consist of reagent grade chemicals or mineral water combined to make moderately hard dilution water according to Methods for Measuring the ¹⁰Safe levels will be determined by Title 11, Part 6, Chapter 2. ¹¹In large rivers, lakes, and estuaries the permittee must provide a schematic map showing isopleths of waste concentrations. Acute Toxicity of Effluents and Receiving Waters to Fresh water and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. For estuarine testing, dilution water shall consist of synthetic seawater or hyper-saline brine combined to achieve a salinity of 20 parts per thousand according to Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. These dilution waters will be deemed acceptable if the survival of the control organisms in the toxicity tests is 90% or greater.

(d) A standard reference toxicant quality assurance test (acute) shall be conducted concurrently with the effluent tests using both species used in the toxicity tests. Alternatively, if a lab conducts monthly QA/QC reference toxicant tests for both species as part of their SOP, these results may be submitted in lieu of the above mentioned concurrent tests. In either case the reference toxicant test results must be submitted in the final report as well as on the Mississippi Office of Pollution Control NPDES Whole Effluent Toxicity Testing Report Form.

3. The permittee shall conduct the first series of tests specified in Section 2 above within 90 days of the commencement of the discharge. The tests shall be conducted quarterly thereafter for twelve (12) consecutive months, provided that the acute LC₅₀ is greater than or equal to the product of 3 times the IWC%. After the first year of testing, the frequency of monitoring will be reduced to once per six months for the life of the permit. Sampling shall be timed to cover the seasonal extremes of the year (hot- dry and cold-wet). The results of these acute toxicity tests shall be reported to the Mississippi Environmental Quality Permit Board on the next quarterly discharge monitoring report. Final acute toxicity test results shall be in report form as outlined in Methods for Measuring the Acute Toxicity of Effluents to Fresh water and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. Along with this report, the permittee must submit a completed Mississippi Office of Pollution Control NPDES Whole Effluent Toxicity Testing Report Form within two weeks following test completion.

4. If either toxicity test results in an LC₅₀ value of less than the product of 3 times the IWC%, the permittee shall initiate a second toxicity test within 2 weeks after the completion of the first toxicity test using the organism(s) that failed. The LC₅₀ determinations from these tests shall be reported to the Mississippi Environmental Quality Permit Board within two weeks after completion of the test.

(a)In the event that the results of any toxicity test reveals that the LC₅₀ of the permittee's effluent is less than the product of 3 times the IWC%, then this finding will constitute a violation of Part I of this permit. In the event the permittee passes the second toxicity test, the permittee shall resume testing in accordance with the testing schedule set forth in the permit. In the event the permittee fails the second WET test, the permittee shall submit a Toxicity Reduction Evaluation Plan (TREP) within 45 days following completion of the follow-up tests to reduce the toxicity of the effluent to safe levels¹². The first phase of the TREP shall include monitoring to characterize the toxicity of the effluent.

(b) In addition to the specific conditions of this permit, the permittee shall comply with all applicable conditions of 40 CFR 122.7 and 40 CFR 122.61 (06-03-93).

¹² Safe levels will be determined by WPC-2.

III. ACUTE WHOLE EFFLUENT TOXICITY MONITORING REQUIREMENTS

1. The permittee shall submit any existing toxicity data for review by the Mississippi Office of Pollution Control within 30 days of the effective date of this permit.

2. The permittee shall perform static, non-renewal, definitive (a control and five effluent concentrations) toxicity tests at 25°C in accordance with Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or the most recent edition. Acute toxicity tests will be conducted on 24-hour composite samples of effluent, and tests must be initiated within 36-hours of completion of the sampling period.

(a) If the Mississippi Office of Pollution Control determines the receiving stream is freshwater, the permittee must use both the following test organisms and test durations:

(1)Pimephales promelas ([LESS THAN] 24-hrs.of age) - 96 hour

(2)Ceriodaphnia dubia - 48 hour

(b) If the Mississippi Office of Pollution Control determines the receiving stream is marine or estuarine, the permittee must use both the following test organisms and test durations:

(1)Menidia beryllina - 96 hour

(2)Americamysis - 48 hour

(c) Dilution water used for these tests shall consist of reagent grade water, defined as distilled or deionized water that does not contain substances which are toxic to the test organisms. For freshwater tests, dilution water shall consist of reagent grade chemicals or mineral water combined to make moderately hard dilution water according to Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Fresh water and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. For estuarine testing, dilution water shall consist of synthetic seawater or hyper-saline brine combined to achieve a salinity of 20 parts per thousand according to Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. These dilution waters will be deemed acceptable if the survival of the control organisms in the toxicity tests is 90% or greater.

3. The permittee shall conduct the first series of tests specified in part 1 above within 90 days of the issuance of the permit. The tests shall be conducted quarterly thereafter for twelve (12) consecutive months. After the first year of testing, the frequency of monitoring will be reduced to once per six months for the life of the permit. Sampling shall be timed to cover the seasonal extremes of the year (hot- dry and cold-wet). The results of these acute toxicity tests shall be reported to the Mississippi Environmental Quality Permit Board on the next quarterly discharge monitoring report. Final acute toxicity test results shall be in report form as outlined in Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition. Along with this report, the permittee must submit a completed Mississippi Office of Pollution Control NPDES Whole Effluent Toxicity Testing Report Form within two weeks following test completion.

4. In addition to the specific conditions of this permit, the permittee shall comply with all applicable conditions of 40 CFR 122.7 and 40 CFR 122.61 (06-03-93).

IV. CHRONIC WHOLE EFFLUENT TOXICITY MONITORING REQUIREMENTS

The Water Quality Standards of Mississippi require that all waters be free from substances in concentrations or combinations which are harmful to humans, animals, or aquatic life (State of Mississippi, Water Quality Criteria for Intrastate and Coastal Waters, Section II.4, Minimum Conditions Applicable to All Waters (current edition). In accordance with such requirements, the permittee is authorized to discharge from outfall(s) only in accordance with the following conditions:

1. The permittee shall submit any existing toxicity data for review by the Mississippi Office of Pollution Control within 30 days of the effective date of this permit.

2. The permittee shall perform 7-day chronic, static renewal, definitive (a control and five effluent concentrations) WET tests in accordance with Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, (EPA/600/489/001) or Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, (EPA/600/4-87/028) or the most recent edition.

(a) Dilution water used for these tests shall consist of reagent grade water, defined as distilled or deionized water that does not contain substances which are toxic to the test organisms. For fresh water tests, dilution water shall consist of reagent grade chemicals or mineral water combined to make moderately hard dilution water according to Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Fresh water Organisms (EPA/600/4-89/001) or most recent edition. For estuarine testing, dilution water shall consist of synthetic seawater or hyper-saline brine combined to achieve a salinity of 20 parts per thousand according to Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms (EPA/600/4-87/028) or most recent edition. These dilution waters will be deemed acceptable if the control organisms in the toxicity tests meet the minimum EPA criteria for chronic tests.

(b) If the Mississippi Office of Pollution Control determines the receiving waters are fresh water, the permittee shall conduct a Ceriodaphnia dubia Survival and Reproduction Test, and a Pimephales promelas Larval Survival and Growth Test on serial dilutions of effluent to determine if the discharge from outfall(s) is chronically toxic. Such testing will determine if the water affects the survival, growth, and reproduction of the test organisms. Static renewal tests will be conducted on three 24- hour composite samples of effluent. The first of these composite samples will be used to set up the tests and for the day 1 and day 2 renewals, the second of these composite samples will be used to renew the tests on days 3 and 4, and the third composite sample will be used to renew the tests on days 5 and 6. Not more than 36 hours will elapse between sampling and the first use of any of the composite samples. The chronic test(s) shall be considered valid only if the acceptability criteria referenced in Short-Term Methods for estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, (EPA/600/4-89/001), or the most recent edition, are met. All data shall be statistically analyzed according to the referenced manual.

(d) A standard reference toxicant quality assurance test (chronic) shall be conducted concurrently with the effluent tests using both species used in the toxicity tests. Alternatively, if a lab conducts monthly QA/QC reference toxicant tests with both species as part of their SOP, these results may be submitted in lieu of the above mentioned concurrent tests results. In either case, the reference toxicant test results must be submitted with the final report as well as on the Mississippi Office of Pollution Control NPDES Whole Effluent Toxicity Testing Report Form within two weeks of test completion. Final chronic toxicity test results shall be in report form as outlined in Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, Fourth Edition, (EPA-600/4-90/027) or most recent edition.

4. These chronic toxicity tests shall be initiated within 90 days of the date of issuance of the permit to evaluate wastewater toxicity. Such chronic toxicity tests shall be conducted once per quarter for a period of one year following the effective date of the permit. After the first year of testing, the frequency of monitoring may be reduced to once per six months for the life of the permit. Sampling shall be timed to cover the seasonal extremes of the year (hot-dry and cold-wet).

5. In addition to the specific conditions of this permit, the permittee shall comply with all applicable conditions of 40 CFR 122.7 and 40 CFR 122.61 (06-03-93).

NPDES Whole Effluent Toxicity Testing Report Form

Mississippi Office of Pollution Control

* All blanks on this form are to be filled in. Blanks that are not used should be filled in with "N/A" or a line drawn through the blank. Please print.

Please attach the following items to this report form and indicate with an "X" in the box.

1. ALL CHAIN OF CUSTODY FORMS

2. All Reference Toxicant Data for each Organism used in Test and Current Control Charts for each Organism.

3. All Raw Data (Bench Sheets) Pertaining to the Tests (i.e., all physical, chemical and biological measurements)

4. All Result Calculations

5. Discharge Monitoring Reports (DMRs) when Applicable

Facility/Industry/Client Name: _____________________________________________________

NPDES Number: ________________________________________________________________

County: _______________________________________________________________________

Name and Phone Number of Contract Laboratory: _____________________________________

Date(s) and Time(s) Test(s) Initiated: _____________________ End: _______________________

Name(s) of Person(s) Conducting Test(s) (Printed): ____________________________________

QA/QC Officer/Reviewer Signature: ________________________________________________

Laboratory Report #: _____________________________________________________________

Sampler's Name (Print): __________________________________________________________

Samples

DATE AND TIME COLLECTED

LAB SAMPLE #

GRAB

24-H COMP.

ARRIVAL TEMP. °C

TYPE OF REFRIG. USED IN TRANS.

SAMPLE DELIVR. BY:

*SAMPLE AERATED

SAMPLE FILTERED

* If samples are aerated please describe in report.

**Reference Toxicant Data

Name of Toxicant: ______________________________________________________________

Dates of Test(s): ________________________________________________________________

Species and Age: ________________________________________________________________

In-house or Commercially Obtained Test Organisms: ___________________________________

LC₅₀ or IC₂₅: ___________________________________________________________________

**Please attach all ref. tox. raw data for each test organism used.

CERIODAPHNIA DUBIA	PIMEPHALES PROMELAS
Test Type: Chronic or Acute
Renewal or Non-renewal
Test Concentrations (% Effluent)
Age of Test Org.
Amount and Type of food
How often fed
Test Chamber Volume
Type of Chamber
# of Org./Chamber
# of reps.
Description of Control Water
Single, Multiple or Continuous Temp. Readings

Test Results (Acute and/or Chronic)

TEST SPECIES

48-HOUR LC₅₀

96-HOUR LC₅₀

IC₂₅ SURVIVAL

IC₂₅ REPR. OR GROWTH

Miss. Code. tit. 11, pt. 6, ch. 1, subch. 2, exh. 11-6-1-2-D to Chapter 1, Subchapters 1 and 2