Interim Environmental Risk Assessment for the Town of...

Interim Environmental Risk Assessment

for the Town of Shippagan

Wastewater Treatment Plant,

in Accordance with the Canada-Wide Strategy for

Municipal Wastewater Effluent

Submitted to: Roy Consultants

3655, rue Principale

Tracadie-Sheila, N.B.

E1X 1E2

Prepared by: NATECH Environmental Services Inc.

109 Patterson Cross Rd.

Harvey Station, N.B.

E6K 1L9

Date: February 24, 2011

Interim CCME Environmental Risk Assessment: Shippagan WWTP

NATECH Environmental Services Inc.

TABLE OF CONTENTS

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 1 -

2. SUBSTANCES OF POTENTIAL CONCERN . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 5 -

2.1 Facility size categorization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 5 -

2.2 Determination of the list of substances of potential concern . . . . . . . . . . - 5 -

2.3 Additional substances associated with industrial discharges . . . . . . . . . . - 5 -

3. INITIAL EFFLUENT CHARACTERIZATION PROGRAM - METHODOLOGY . . . - 7 -

4. RECEIVING WATER BODY CHARACTERIZATION . . . . . . . . . . . . . . . . . . . . . . - 9 -

4.1 Water body physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 9 -

4.2 Resource usage downstream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 14 -

4.3 Background stream water quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 14 -

4.4 Field reconnaissance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 15 -

5. INITIAL EFFLUENT CHARACTERIZATION PROGRAM - RESULTS . . . . . . . . - 19 -

6. DETERMINATION OF EFFLUENT DISCHARGE OBJECTIVES (EDOs) . . . . . - 21 -

6.1 Determination of Environmental Quality Objectives (EQOs) . . . . . . . . . - 21 -

6.2 Determination of the mixing zone and assessment of dilution . . . . . . . . - 24 -

6.3 Determination of EDOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 25 -

7. SELECTION OF SUBSTANCES FOR COMPLIANCE MONITORING . . . . . . . - 27 -

7.1 Selection of substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 27 -

7.2 Selection of monitoring frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 27 -

8. CONCLUSIONS AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . - 29 -

9. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 30 -

10. GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 31 -

APPENDIX A - Photographs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 35 -


NATECH Environmental Services Inc. - 1 -

1. INTRODUCTION

The Canada-wide Strategy for the Management of Municipal Wastewater Effluent was

released by the Canadian Council of Ministers of the Environment (CCME) in 2009 to

improve the protection of human health and the environment, and to provide better clarity

in the way municipal wastewater effluent is managed across the country. The strategy is

based on preparing a site-specific Environmental Risk Assessment (ERA) for each

municipal wastewater treatment plant in the country. The Province of New Brunswick is

a signatory to the strategy and has requested that the Town of Shippagan starts the one-

year water quality monitoring program in 2010 for its wastewater treatment plant (WWTP).

The ERA for the facility should be completed by December 31, 2011. To take advantage

of provincial funding assistance, an interim ERA report is to be prepared in the winter of

2011 and to be completed after the initial effluent characterization is finished in 2011.

NATECH Environmental Services Inc. was asked by the Roy Consultants to carry out the

ERA.

The objective of this ERA is to provide Effluent Discharge Objectives for the WWTP based

on the assimilative capacity of the local receiving environment. Figure 1-1 shows the

location of the WWTP. The plant consists of two lagoon cells, one of which is aerated. The

effluent is not disinfected. The treated wastewater is discharged into a surface drainage

ditch which becomes a meandering brook in the salt marsh of the Shippagan Channel.

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FIGURE 1-1

SHIPPAGANCHANNEL

INTERIM CCME ENVIRONMENTAL RISK ASSESSMENT

SHIPPAGAN WWTP

SITE LOCATION



The methodology used to carry out this investigation is in accordance with the ERA

framework outlined in the technical supplements of the CCME Strategy:

� A one year characterisation of the effluent is carried out by the municipality, including

flow monitoring, sampling for chemical parameters, and toxicity tests. The number

of parameters, and the frequency of sampling depend on the size of the municipality.

� Valued human and environmental health components (HEHCs) downstream of the

effluent discharge (including recreation and bodily contact, aquatic life, recreational

and commercial harvesting of fish, drinking water supplies, irrigation, etc.) are

determined as part of this study, in consultation with local stake holders.

� Environmental Quality Objectives (EQOs) are determined. An EQO is the

concentration of a substance in the environment considered safe for aquatic life and

for human uses.

� An allocated mixing zone (MZ) in the receiving water body is determined: the MZ is

the extent of the water body around the outfall where the effluent is initially diluted,

and where contaminant concentrations greater than the EQOs are authorised by the

regulators.

� The target Effluent Discharge Objectives (EDOs) are determined. The EDOs are

maximum acceptable concentrations in the effluent from the WWTP. The EDOs

are calculated based on worst-case conditions to ensure that the EQOs are met at

all times at the edge of the mixing zones.

� Compliance monitoring requirements are determined, specifying what parameters

should be regularly tested, and at what frequency, after the one-year



characterisation has been completed.

The process of determining EDOs involves a combination of documentation review,

consultation with stake holders, field investigations and mathematical plume dispersion

modeling. The field investigations include monitoring of water levels, stream flows, and

water quality. The bathymetry is surveyed and a dye tracer is released into the effluent and

tracked for several hours, to visually observe the path and mixing of the effluent plume.



2. SUBSTANCES OF POTENTIAL CONCERN

2.1 Facility size categorization

Based on wastewater flow, the Shippagan WWTP is characterized as a “medium” category

facility (2,500 to 17,500 m3/day), according to the definitions in the CCME Strategy.

zaTheoretically, for approximately 1522 buildings (1188 residential, 310 commercial, 24

industrial) connected to the WWTP the annual average daily wastewater flow would be

2,100 m3/day (assuming 1.4 m3/day/building), and the peak flow may reach 6,400 m3/d

(assuming three times that flow).

2.2 Determination of the list of substances of potential concern

The substances of potential concern for a medium-size facility such as the WWTP from

Shippagan are listed in Table 2.1, based on CCME (2009).

2.3 Additional substances associated with industrial discharges

No additional substances from industrial discharges were identified. Most of the fish

processing plants in Shippagan are discharging directly into the harbour.



Table 2.1. List of Substances Potential Concern for Shippagan WWTP

Test Group Substances

General Chemistry /Nutrients

Carbonaceous Biochemical Oxygen Demand (CBOD5)Chemical Oxygen Demand (COD)Total Suspended Solids (TSS)Total Ammonia Nitrogen Total Kjeldahl Nitrogen (TKN)Total Phosphorus (TP)pH, TemperatureCyanide (total)FluorideNitrateNitrate + Nitrite

Pathogens E. coliFaecal coliforms

Metals Aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium,cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel,selenium, silver, strontium, thallium, tin, titanium, uranium, vanadium, zinc

OrganochlorinePesticides

Achlordane, Aldrin, alpha-BHC, DDT, dieldrin, endosulfan (I and II), endrin, g-chlordane, heptachlor epoxide, lindane (gamma-BHC), methoxychlor, mirex, toxaphene

PolychlorinatedBiphenyls (PCBs)

Total PCBs

Polycyclic AromaticHydrocarbons(PAHs)

Acenaphthene, acenaphthylene, anthracene, benzo(a)anthracene,benzo(a)pyrene, benzo(b)fluoranthene, benzo(g,h,i,)perylene,benzo(k)fluoranthene, chrysene, dibenz(a,h)anthracene, fluoranthene,fluorene, indeno(1,2,3-cd)pyrene, methylnaphthalene, naphthalene,phenanthrene, pyrene

Volatile OrganicCompounds (VOCs)

Benzene, bromodichloromethane, bromoform, carbon tetrachloride,chlorobenzene, chlorodibromomethane, chloroform, 1,2-dichlorobenzene,1,4-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethene,dichloromethane, ethylbenzene, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane, tetrachloroethene, toluene, trichloroethene, vinylchloride m/p-xylene, o-xylene

Phenoliccompounds

2,3,4,6–tetrachlorophenol, 2,4,6-trichlorophenol, 2,4-dichlorophenol,pentachlorophenol

Surfactants Non-ionic surfactants and anionic surfactants (others may be added bythe jurisdiction)



3. INITIAL EFFLUENT CHARACTERIZATION PROGRAM - METHODOLOGY

Table 3.1 summarises at what frequency the substances of concern have to be measured

for a period of one year for a medium-size facility.



Table 3.1: Monitoring requirements for a period of one year, for Shippagan WWTP

ParameterSampling

frequencyProcedure

Anticipated

schedule

Flow Daily Measured by

operator

Dec. 2010 to

Dec. 2011

CBOD5 and BOD5 (1) Every two

weeks

Sampled by

operator,

analysed by

laboratory

Dec. 2010 to

Dec. 2011TSS

NH3-N Total (NH3+NH4+)

TKN

TP

E. Coli

Faecal coliforms (2)

pH Measured by

operator Temperature

COD (chem. oxygen demand) Quarterly Sampled by

operator,

analysed by

laboratory

Jan. 2011

April 2011

July 2011

Oct. 2011

Fluoride

Nitrate

Nitrate +Nitrite

Cyanide (total)

Metals, metal hydrides, mercury

Organochlorine pesticides (15 substances)

PCBs

PAHs (17 substances)

VOCs (20 substances)

Phenolic compounds (4 substances)

Surfactants (non-ionic and anionic)

Acute toxicity (Rainbow trout)

Acute toxicity (Daphnia magna)

Chronic Toxicity (Ceriodaphnia dubia)

Chronic Toxicity (Fathead minnow) optional

(1) BOD5 only three times to establish a correlation with CBOD5

(2) Added to allow an assessment of the impact on shellfish



4. RECEIVING WATER BODY CHARACTERIZATION

4.1 Water body physical characteristics

The outfall is located in a small unnamed ditch that flows through a coastal wetland and into

Shippagan Channel. The distance between the outfall and the open ocean is

approximately 300 m. (see Figure 4-1). Figure 4-2 shows a hydrographic chart of the area.

Table 4.1 summarises the characteristics of the receiving brook. The drainage area of the

brook upstream of the discharge in the order of 0.5 km2. The flows were prorated based on

the closest available gauging station located on the Caraquet River. The average flow is

calculated to be 11 L/s, and the 7 day-10 year (7DQ10) low flow 1.4 L/s.

Predicted water levels for Shippagan (Station #2071) obtained from the Canadian

Hydrographic Service (2010) are plotted on Figure 4-3 for July and August 2010. Over that

period, the levels varied between 0.1 m and 2.1 m above chart datum (the lowest low water

level, with an average of 0.9 m. Table 4.2 summarises tidal statistics from the local

hydrographic chart for Shippagan Gully.



Table 4-1. Characteristics of local rivers

Parameter Caraquet River at

Burnsville

Station 01BL002

Unnamed ditch upstream

of Shippagan WWTP

outfall

Drainage area (km2) 173 0.5

Flow regime unregulated unregulated

Average annual flow (L/s) 3,640 11

1:10 year - 7 day (7DQ10)

low flow (L/s)

467 (1) 1.4

(1) From Environment Canada (1990)

Table 4.2. Characteristics of tidal water levels in Shippagan Gully (from Nautical Chart #

4486), relative to Chart Datum (CD). The mean sea level is at 0.7 m above CD.

Parameter Mean tides Large tides

Low water level (m) 0.2 0.1

High water level (m) 1.3 1.7

Range (m) 1.1 1.6

SHELLFISHCLOSURE AREAS

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SHELLFISH CLOSURE AREAS

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WATERSHED AREAAPPROX. 0.5 SQ. KM. DISCHARGE

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FIGURE 4-2


SHIPPAGAN WWTP

HYDROGRAPHIC CHART

SHIPPAGAN CHANNEL20453031

Shippagan - Predicted tidal water level changes in the summer of 2010 (Source: CHS)

0

0.5

1

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2

2.5

Jul.8 00:00 Jul.15 00:00 Jul.22 00:00 Jul.29 00:00 Aug.5 00:00 Aug.12 00:00 Aug.19 00:00

Wat

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vel a

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(m)

Field work

NATECH Environmental Services Inc. Figure 4-3Interim CCME Environmental Risk Assessment: Shippagan WWTP



4.2 Resource usage downstream

Figure 4-1 shows the shellfish closure orders that are currently in effect in the area. To

assess the potential environmental protection components, the Canadian Water Quality

Guidelines for the Protection of Aquatic Life (CCME, 2007), and the Canadian Recreational

Water Quality Guidelines and Aesthetics (CCME, 1999) were consulted.

4.3 Background stream water quality

No historical background water quality data are available for the brook receiving the effluent

in Shippagan.



4.4 Field reconnaissance

The following conditions were observed during field work carried out on August 2, 2010:

� The tidal range of the falling tide and following rising tide during the mixing zone

measurements were 0.7 m and 0.8 m respectively (see Figure 4-4). The freshwater

flow in the unnamed brook receiving the lagoon effluent was close to zero on August

2, based on observations and the measured dye dilution.

� Drifters were released at the bridge to Lameque Island (see Figure 4-5) and the

following was observed: at 10:30, the current was nearly stagnant, flowing toward

Shippagan Channel; at 13:50, the velocity was 0.63 m/s in the same direction.

� The effluent flow at 11:00 was approximately 30 L/s (which would correspond to

2,600 m3/day). A dye tracer (Rhodamine WT) was released into the effluent flow

from 12:00 to 15:00. A total of 250 mL of dye was released. Figure 4-5 illustrates

the shape of the observed mixing zone. The effluent was found to drift in a very thin

layer on the surface out into the Channel. The growth of aquatic vegetation, as

visible on the aerial photography, seems to coincide with the measured dilution.

� Water quality measurements were taken in the effluent stream, as well as upstream

and downstream of the outfall by NATECH on August 2, 2010. Also, samples were

collected at the same locations and sent to an independent laboratory. The results

are detailed in Table 4.4.

� Photographs of the discharge are shown in Appendix A.

Shippagan - Measured tidal water level changes during the field work

0

0.5

1

1.5

2

2.5

Aug.2 00:00 Aug.2 06:00 Aug.2 12:00 Aug.2 18:00 Aug.3 00:00 Aug.3 06:00 Aug.3 12:00

Wat

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vel a

bove

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(m)

Tidal water level predictions for Shippagan (Source: CHS)

Water level measured in Shippagan Channel

NATECH Environmental Services Inc. Figure 4-4Interim CCME Environmental Risk Assessment: Shippagan WWTP

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FIGURE 4-5


SHIPPAGAN WWTP

EFFLUENT PLUME DILUTION

SHIPPAGANCHANNEL

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Table 4.4: Water quality of the receiving water body near the Shippagan WWTP outfall, and

the effluent, on August 2, 2010.

Parameter Unit Upstream Effluent Downstream

Field measurements

DO mg/L 7.5 10.0 10.1

pH units 8.4 8.5 8.1

Temperature °C 24.0 22.2 24.5

TDS mg/L 27.0 3.4 26.8

Conductivity mS/cm 41.6 5.2 38.5

Salinity ppt 26.6 2.8 25.8

Lab analyses

CBOD5 mg/L



5. INITIAL EFFLUENT CHARACTERIZATION PROGRAM - RESULTS

Historical data for the past year were obtained from the WWTP operator and are

summarised in Table 5.1. Data from the one-year monitoring program are summarised in

Table 5.2.

Table 5.1: Historical effluent characteristics for May to November 2009

Parameter Unit Min Max Average

Plant data

DO mg/L 2.7 15.2 9.4

pH units 6.7 9.8 7.9

Temperature °C 4.3 26.5 14

Laboratory analyses

CBOD5 (1) mg/L 10

TSS (1) mg/L 26

NH3-N Total (1)

(NH3+NH4+)

mg/L 0.3

TKN (1) mg/L 1.2

TP (1) mg/L 0.49

pH (1) units 8.2(1) From one sample on May 13, 2009



Table 5.2: Effluent characteristics from December 2010 to December 2011

(Only data for the first two months were available at the time of writing the report)

Parameter Unit Min Max AveragePlant datapH mg/L 7.7Temperature mg/L -0.1Laboratory analysesCBOD5 mg/L 4 14 9BOD5 mg/L 7 9 8TSS mg/L 11 19 14NH3-N Total (NH3+NH4

+) mg/L 1.8 4.6 3.1TKN mg/L 6 41 15TP units 0.59 0.92 0.77E. Coli MPN/100mL 1,620 64,880 19,630COD (chem. oxygen demand) mg/L 30Fluoride mg/L 0.32Nitrate mg/L 1.9Nitrate +Nitrite mg/L 1.9Cyanide (total) mg/L



6. DETERMINATION OF EFFLUENT DISCHARGE OBJECTIVES (EDOs)

6.1 Determination of Environmental Quality Objectives (EQOs)

Guideline values for relevant water quality parameters were obtained from the Canadian

Water Quality Guidelines for the Protection of Aquatic Life (CCME, 2007), and the

Canadian Recreational Water Quality Guidelines and Aesthetics (CCME, 1999). The

values are summarised in Table 6.1.



Table 6.1 Environmental Quality Objectives (EQOs) for Shippagan WWTP

Parameter* Unit EQOs based on Canadian

Water Quality Guidelines

Marine & estuarine

DO (related to CBOD5) mg/L >8.0 (1)

TSS mg/L



(1) Dissolved oxygen: Marine/estuarine waters: “The recommended minimum concentration of DO in marine and estuarine watersis 8.0 mg/L. Depression of DO below the recommended value should only occur as a result of naturalprocesses. When ambient DO concentrations are >8.0 mg/L, human activities should not cause DO levelsto decrease by more than 10% of the natural concentration expected in the receiving environment at that time.”(CCME, 2007)

(2) Suspended solids:Maximum increase of 25 mg�L-1 from background levels for any short-term exposure (e.g., 24-h period).Maximum average increase of 5 mg�L-1 from background levels for longer term exposures (e.g., inputs lastingbetween 24 h and 30 d) (CCME, 2007)

(3) Ammonia:There is no recommended guideline for marine aquatic life from CCME.The following values for total NH3-N were determined based on values used in BC (Nordin, 2001), assuminga salinity of 30 ppt, a sea temperature of 20 deg. C, and a pH of 8.0:



6.2 Determination of the mixing zone and assessment of dilution

The extent of a mixing zone varies with each water quality parameter. For most

parameters, dilutions should be calculated for the edge of the near-field mixing zone. The

near-field mixing zone is the part of the water body where the energy contained in the

effluent (mainly momentum and buoyancy) is dissipating and is the main cause of effluent

dilution. In the far-field, effluent dilution is solely dependent on transport and dispersion by

the ambient current. Most effluent constituents exhibit their strongest impact in the near-

field where their concentrations are the highest. However, the impact of certain

parameters, such as BOD and nutrients (nitrogen and phosphorus) can be felt further

downstream, sometimes days after the release, once biological processes make use of the

material. In that case, a larger part of the receiving water body has to be considered to be

part of the mixing zone.

In New Brunswick, a mixing zone should not occupy more than 25% of cross-sectional area

or volume of flow of the receiving watercourse, during 7 day - 10 year low flow conditions.

Here the effluent flows into a ditch that is likely dry during most of the year. The ditch

discharges into a coastal wetland within 100 m from the outfall. For the purpose of this

study, the point of discharge was considered to be at the mouth of the ditch. We

recommend to use the following parameter-specific allocated mixing zones:

� For CBOD5, TSS, TKN, and TP: the edge of the small cove where the mouth of the

ditch is located. This zone extends from the mouth of the ditch up to the

approximately 200 m into the channel. A dilution of 1 in 100 was measured at that

point in August 2010. Beyond that distance, the diluted effluent leaves the cove and

is entrained into the main channel.



� For all other parameters: the near-field mixing zone should be used. This zone was

observed to extend approximately 80 m into the cove at the mouth of the ditch. A

dilution of 1 in 20 was measured at that location during the field work.

6.3 Determination of EDOs

The Effluent Discharge Objectives (EDOs) in Table 6.4 below are calculated based on the

Environmental Quality Objectives (EQOs) in Table 6.1, the dilutions available at the edge

of the allocated mixing zones, and background concentrations in the receiving water body.



Table 6.4: Proposed future EDOs for the Shippagan WWTP

Parameter* Unit

Assumed

back-

ground

Allocated

MZ

Dilution at

edge of MZ EQO (1)

Calculated

EDO for

effluent

CBOD5 mg/L 5 200 m 100



anticipated to be found in the effluent and have been omitted at this stage.

(1) From Table 6.1

(2) Minimum National Performance Standards mentioned in the CCME Strategy

(3) Maximum increase of 25 mg�L-1 from background levels for any short-term exposure (e.g., 24-h period).

Maximum average increase of 5 mg�L-1 from background levels for longer term exposures (e.g., inputs lasting

between 24 h and 30 d) (CCME, 2007)

(4) EDOs for organochlorine pesticides, PAHs, and VOCs will be examined in the final report when more data

from the effluent characterization program are available.

7. SELECTION OF SUBSTANCES FOR COMPLIANCE MONITORING

7.1 Selection of substances

The substances that will have to be monitored after the one-year characterization period

is finished include:

- TSS,

- CBOD5,

- Other substances that exceed EQOs during the initial characterization,

- Substances with mean effluent values greater than 80% of established EDOs.

7.2 Selection of monitoring frequencies

Table 7.1 details the monitoring frequencies required by the CCME Strategy for the above

substances, for a medium-size facility like the Shippagan WWTP.



Table 7.1 Compliance monitoring requirements for the Shippagan WWTP.

Parameter Sampling frequency Procedure

CBOD5 Every 2 weeks Sampled by operator,

analysed by laboratoryDO

TSS

NH3-N Total (NH3+NH4+), if

applicable

TKN

TP

E. Coli

Faecal coliforms

pH Measured by operator

Temperature

Other * To be defined by

jurisdiction

Sampled by operator,

analysed by laboratoryAcute toxicity (Rainbow trout) Quarterly Sampled by operator,

analysed by laboratoryAcute toxicity (Daphnia magna)

Chronic Toxicity (Ceriodaphnia

dubia)

* Any other substances that exceeded their EDO during the one-year characterization



8. CONCLUSIONS AND RECOMMENDATIONS

The outfall from the Shippagan aerated lagoon discharges without disinfection into a surface

drainage ditch. During the low flow periods, the effluent constitutes most of the flow in the

ditch. After 100 m, the effluent enters a coastal marsh that is emptied and filled with the

tides.

Dye testing showed that the effluent spreads in a very thin layer over a significant part of a

cove in Shippagan Channel. The growth of aquatic vegetation as observed on aerial

photography seems to coincide with the 1:100 dilution limit. The coastal transport

processes in Shippagan Channel are likely very effective in transporting residual effluent out

to sea.

The receiving water is being used for recreational purposes, both with and without physical

contact. The potential for fishing and shell fish harvesting also exists, but currently all of

Shippagan Channel is closed to shell fish harvesting. Given the many other sources of

faecal bacteria in the area, it is not likely that disinfection of the wastewater treatment plant

effluent will have a significant effect on the shellfish harvesting closure. However,

disinfection would assist with meeting the aquatic guidelines for human contact.

The high nitrogen concentration in the effluent is the likely cause of the observed aquatic

vegetation. Effluent polishing (for example through sand filtration or engineered wetlands)

can be used to remove nitrogen if desired in the future.



9. REFERENCES

Canadian Council of Ministers of the Environment. 1999. Recreational water quality

guidelines and aesthetics. In: Canada Environmental Quality Guidelines, 1999, Canadian

Council of Ministers of the Environment, Winnipeg.

Canadian Council of Ministers of the Environment. 2000. Canadian water quality guidelines

for the protection of aquatic life: Ammonia. In: Canada Environmental Quality Guidelines,

1999, Canadian Council of Ministers of the Environment, Winnipeg.


for the protection of aquatic life: Nutrients: Canadian Guidance Framework for the

Management of Near shore Marine Systems. In: Canada Environmental Quality Guidelines,

1999, Canadian Council of Ministers of the Environment, Winnipeg.


for the protection of aquatic life: Summary table. Updated December, 2007. In: Canada

Environmental Quality Guidelines, 1999, Canadian Council of Ministers of the Environment,

Winnipeg.

Canadian Council of Ministers of the Environment. 2009. Canada-wide Strategy for the

Management of Municipal Wastewater Effluent. Available online at:

http://www.ccme.ca/ourwork/water.html?category_id=81

Comeau, Nada. 2004. “Rapport d’étape de la qualité des eaux de surface pour les bassins

versants de la Grande et Petite Rivière Tracadie”. Prepared for the Association des

Bassins Versants de la Grande et Petite Rivière Tracadie, and the Department of

Environment and Local Government.

Environment Canada. 1990. Low Flow Estimation Guidelines for New Brunswick.

Environment Canada/Inland Waters & NB ENV/Water Resource Planning.



10. GLOSSARY

A

Acutely Lethal (Létal aigu)

At 100 percent concentration of effluent, more than 50 percent of the test species subjected

to it over the test period are killed when tested in accordance with the acute lethality test set

out in the appropriate method. For rainbow trout this is Reference Method EPS 1/RM/13.

Allocated Mixing Zone (Zone de mélange allouée): see mixing zone

Ammonia (Ammoniac)

Total ammonia expressed as nitrogen. Total ammonia means the sum of the unionized

ammonia (NH3) and ionized ammonia (NH4+) species which exist in equilibrium in water.

Analytical methods measure and typically report on ammonia nitrogen as opposed to total

ammonia. The unionized ammonia (NH3) is toxic to fish in low concentrations. The amount

of NH3 is calculated as a fraction of the total nitrogen, based on temperature and pH.

C

Canadian Environmental Quality Guidelines (Recommandations canadiennes pour la

qualité de l’environnement)

Nationally endorsed, science-based goals for the quality of atmospheric, aquatic, and

terrestrial ecosystems. Environmental quality guidelines are defined as numerical

concentrations or narrative statements that are recommended as levels that should result

in negligible risk to biota, their functions, or any interactions that are integral to sustaining

the health of ecosystems and the designated resource uses they support. Developed by

CCME.

Carbonaceous Biochemical Oxygen Demand (CBOD5, 5-day) (Demande biochimique

en oxygène des matières carbonées [DBO5C, 5 jours])



A measure of the quantity of oxygen used in the biochemical oxidation of organic matter in

5 days, at a specific temperature, and under specified conditions. The method of analysis

is defined by Method 5210 in Standard Methods. The CBOD is a fraction of the total BOD.

This fraction is specific to each effluent.

Chronic Toxicity (Toxicité chronique)

The ability of a substance or mixture of substances to cause harmful effects over an

extended period, usually upon repeated or continuous exposure sometimes lasting for the

entire life of the exposed organism. Chronic toxicity results in reduced reproductive capacity

or reduced growth of young, in fish or invertebrate populations.

Combined Sewer (Égout unitaire)

A sewer intended to receive both sanitary waste and storm water.

Combined Sewer Overflow (CSO) (Débordement d’égout unitaire [DEU])

A discharge to the environment from a combined sewer system that occurs when the

hydraulic capacity of the combined sewer system has been exceeded, usually as a result

of rainfall and/or snow melt events.

D

Designated Area (Zone désignée)

Sensitive areas as identified by the regulator and that may be affected by municipal

wastewater discharges, such as fish spawning sites, beaches, drinking water intakes, etc.



E

Effluent Discharge Objective (EDO) (Objectif environnemental de rejet [OER])

Concentration, load or toxicity units that should be met at the municipal wastewater effluent

discharge to adequately protect all water uses in the receiving environment. Effluent

discharge objectives are obtained through an environmental risk assessment methodology

using the principles of assimilative capacity and mixing zone, in conjunction with

environmental quality.

Environmental Quality Objective (EQO) (Objectif de qualité de l’environnement [OQE])

Concentration of a substance considered safe for aquatic life and for the human uses that

exist or should exist outside of a determined mixing zone. The Canadian Environmental

Quality Guidelines (CEQG) are generic EQOs often used in Canada. The numerical

concentrations or narrative statements that establish the conditions necessary to support

and protect the most sensitive designated use of water at a specified site (CCME, 1987)

Environmental Risk Assessment (ERA) (Évaluation des risques environnementaux

[ERE])

A procedure that will enable the establishment of effluent discharge objectives for

substances of concern. This process will take into account the characteristics of the effluent

and of the site-specific receiving environment. The environmental risk assessment includes

a one-year period where a facility will characterize its effluent (initial characterization).

Eutrophication: Excessive growth of aquatic vegetation in response to elevated

concentrations of nutrients (often associated with wastewater discharges).



M

Mixing Zone (Zone de mélange)

Also called the initial dilution zone. The area contiguous with a point source (effluent

discharge site) or a delimited non-point source where the discharge mixes with ambient

water and where concentrations of some substances may not comply with water quality

guidelines or objectives. For the purpose of the Strategy, “mixing zone” means the

“allocated mixing zone” at the edge of which environmental quality objectives should be met.

N

Near-Field Mixing Zone The volume of water between the end of the discharge pipe orthe diffuser nozzle, and the point where the energy (mainly momentum and buoyancy) of

the effluent has dissipated. Beyond this point - in the far-field - river or coastal current

transport takes over.

Nutrient (Élément nutritif)Any substance that is assimilated by organisms and promotes growth; generally applied to

nitrogen and phosphorus in wastewater, but also to other essential and trace elements.

R

Receiving Environment (Milieu récepteur)

The water body into which effluent is discharged.

S

Streeter Phelps algorithm: A method of predicting oxygen depletion in a receiving waterbody as a function of organic loadings and existing background condition.


NATECH Environmental Services Inc.

APPENDIX A - Photographs

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ceiving Water

Receiving water

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egetation ne

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Aerated La

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Dye discharge

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Outlet P

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i

CCME - Roy - Shippagan - TextCCME - Roy - Shippagan - Fig 1-1 Site LocationCCME - Roy - Shippagan - Fig 4-1 Shellfish closuresCCME - Roy - Shippagan - Fig 4-2 Hydrographic chartCCME - Roy - Shippagan - Fig 4-3 Tidal water levels summer 2010CCME - Roy - Shippagan - Fig 4-4 Tidal water levels during field workCCME - Roy - Shippagan - Fig 4-5 Effluent DilutionCCME - Roy - Shippagan - Appendix A - Photos

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