Assessment of Odour Effects - Waikato · 2019. 1. 3. · AECOM Assessment of Odour Effects...

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Massey Farms Limited

09-Apr-2018

Assessment of Odour Effects

Proposed Chicken Shed Expansion

AECOM




Proposed Chicken Shed Expansion

Client: Massey Farms Limited

ABN: N/A

Prepared by

AECOM New Zealand Limited

8 Mahuhu Crescent, Auckland 1010, PO Box 4241, Auckland 1140, New Zealand

T +64 9 967 9200 F +64 9 967 9201 www.aecom.com

09-Apr-2018

Job No.: 60559186

AECOM in Australia and New Zealand is certified to ISO9001, ISO14001 AS/NZS4801 and OHSAS18001.

© AECOM New Zealand Limited (AECOM). All rights reserved.

AECOM has prepared this document for the sole use of the Client and for a specific purpose, each as expressly stated in the document. No other

party should rely on this document without the prior written consent of AECOM. AECOM undertakes no duty, nor accepts any responsibility, to any

third party who may rely upon or use this document. This document has been prepared based on the Client’s description of its requirements and

AECOM’s experience, having regard to assumptions that AECOM can reasonably be expected to make in accordance with sound professional

principles. AECOM may also have relied upon information provided by the Client and other third parties to prepare this document, some of which

may not have been verified. Subject to the above conditions, this document may be transmitted, reproduced or disseminated only in its entirety.

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Table of Contents

1.0 Introduction 1 1.1 Site Description 1

2.0 Proposed Activities 2 2.1 Description of the Proposed Farm 2 2.2 Sources of Odour 2

2.2.1 Potential Sources of Odour 2 2.2.2 Proposed Mitigation Measures 2

3.0 Assessment Criteria for Odour 4 The assessment contained in this report has considered the matters outlined in the

following statutory documents: 4 3.1 National Assessment Criteria 4 3.2 Regional Assessment Criteria 4

3.2.1 Waikato Regional Plan 4 4.0 Assessment Methodology 8

4.1 Qualitative Assessment Methodology (FIDOL) 8 4.2 Sensitive Receptors 9 4.3 Field Odour Investigation 10 4.4 Wind Speed and Wind Direction 10

5.0 Odour Assessment 15 5.1 Field Odour Investigation 15

5.1.1 Two Weeks After Placement (4 December 2017) 15 5.1.2 Four Weeks After Placement (18 December 2017) 15 5.1.3 Six Weeks After Placement (28 February 2018) 17 5.1.4 Harvest and Shed Clean-out (5 March 2018) 18 5.1.5 Field Odour Investigation Findings (4 December 2017) 19 5.1.6 Field Odour Investigation Findings (18 December 2017) 19 5.1.7 Field Odour Investigation Findings (28 February 2018) 20 5.1.8 Field Odour Investigation Findings (5 March 2018) 20

5.2 Odour Assessment 21 5.2.1 Frequency 22 5.2.2 Intensity 22 5.2.3 Duration 23 5.2.4 Offensiveness 23 5.2.5 Location 23

6.0 Conclusion 25 7.0 Limitations 26

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1.0 Introduction

Massey Farms Limited (Massey Farm) operates a poultry meat grower farm at 98 Massey Road, Aka Aka. The farm currently consists of four climate-controlled growing sheds that are consented to raise a combined total of approximately 180,000 birds.

Massey Farm proposes to expand its existing operation with the construction of four new sheds similar in size to the current sheds. The four proposed sheds will increase the number of chickens to double the current numbers, however Massey Farm intend to control bird numbers via a stocking rate of 38 kilograms of live weight per square metre for barn raised birds or 34 kilograms of live weight per square metre for free range operations. It is Massey Farm’s intention to operate these new sheds as free range, however they would like the option to use the sheds for solely indoor growing in the future if the market changes.

Following submission of the application the Waikato Regional Council has requested, under Section 92 of the Resource Management Act (1991), that an additional odour assessment was required to support the application. AECOM New Zealand Limited (AECOM) has been engaged to assess the air discharges, and in particular odour, from Massey Farm. AECOM has undertaken odour observations of existing operations, and prepared a FIDOL assessment based on these observations. The findings of this assessment are presented in the following sections of this report.

1.1 Site Description

Massey Farm is located at 98 (Part Lot 1 DP 16679) Massey Road, Aka Aka, and covers over 29 hectares of land. The site is located approximately 8 km southwest of the Pukekohe Township. The site is undulating with the contours of the site falling to the north, with the sheds being located at a lower level than the remaining site. There is a crest located to the south of the sheds that falls to the east and south. The surrounding area is used for pastoral grazing, with the land further to the northeast rising to a bluff.

The location of the Project Site is shown in Figure 1.

Figure 1 Site Location

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2.0 Proposed Activities

2.1 Description of the Proposed Farm

Massey Farm is proposing to build an additional four sheds, bringing the total number of sheds on-site

to eight. The four original sheds will continue to operate as indoor growing, and the four additional

sheds will most likely be used for free range operations, but they might also be used for indoor use if

required. Each shed is designed to accommodate up to 45,000 birds, based on indoor operations, this

would equate to a maximum of 360,000 birds on site. The proposed new sheds will be run in

conjunction with an outside yard area. In accordance with free range requirements the bird stocking

density will be a maximum density of between 34 kilograms per square metre, which will reduce the

overall number of birds on-site.

Chicks are brought onto the site when they are one day old. They are reared on a wood shavings litter base, fed pelletised food and supplied water via automatic systems. Food is delivered to the site by trucks and stored on-site in silos. When necessary, sheds are heated by reticulated gas from the gas cylinder compound on the site. Ventilation rates and humidity are independently computer controlled for each shed.

The chickens are harvested between day 31 and 42 of the growing cycle. Generally half of the birds from each shed are removed at day 31 with further harvests taking place later in the cycle depending on the end client requirements. Birds are removed by means of specialist transport trucks and equipment, and taken to the Van Den Brinks processing factory. Typically, birds are removed from one shed at a time, in a procedure that minimises distress, injury and discomfort, in accordance with Code of Welfare.

Once all the chickens have been removed, a contractor removes the litter from the floor of the sheds and it is pushed to the north-eastern end of each shed and then loaded directly onto a truck and trailer. Once the truck is full it is sealed and taken off-site. The litter is removed from the site within 1 to 2 hours.

After the removal of litter, the internal area of the sheds are washed down and sanitised. The sheds

are then stood down for 7 to 10 days before a new batch of chickens is brought onto the site.

2.2 Sources of Odour

Chicken farming operations are often identified as having the potential to generate odours, primarily from the excretion that collects in the litter. However, based on other work undertaken by AECOM, this is not the reality for the majority of farms in New Zealand, particularly the larger, more modern farms of which the current and proposed operations at Massey Farm falls within.

2.2.1 Potential Sources of Odour

The main potential sources of odour from the proposed farm are:

Litter, when chickens are young, the litter inside the shed is relatively dry and generates little or no odour. As the chickens grow older, the litter becomes more saturated and is associated with higher concentrations of odour.

Litter and bird removal operations.

2.2.2 Existing and Proposed Mitigation Measures

The most significant factor in reducing odour emissions from the proposed new farm layout is that the birds for the new sheds are free range, and therefore excretion is not always confined to inside the sheds, and therefore there is less build-up in the litter during the growing cycle and less potential for odour. In addition the site will implement the following mitigation measures to control odour, which are also applicable if the sheds are to be used for indoor only growing:

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The sheds make use of an advanced computer controlled system that manages ventilation, particularly from the crucial early stage, when the birds are confined to the sheds.

Odour can also be caused by the chicken litter becoming too wet, whereas dust is caused by the litter becoming too dry. Both problems can be managed effectively by the computer system in each shed, which monitors the weight and age of the birds in relation to the humidity levels and air temperatures both inside and outside the building, and manages ventilation. The computer controls in each shed calculate the changes in climate required to maintain optimum conditions for the birds and adjust the venting of the sheds accordingly.

Litter is removed at the end of each batch of birds by specialist cleaning contractors in order to minimise the odour potential from this source. The litter is removed from the shed and then removed on the same day (within 1 - 4 hours) by a contractor. No litter is disposed of on the applicant’s site.

Improved diets for meat grower chickens which has resulted in substantially lower moisture levels in the litter.

Wash down water is minimised and is irrigated to adjoining land as soon as practical.

Sheds are insulated to a high standard thereby reducing the moisture content of the litter.

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3.0 Assessment Criteria for Odour

The assessment contained in this report has considered the matters outlined in the following statutory

documents:

Resource Management Act 1991 (RMA); and,

Waikato Regional Plan (WRP).

3.1 National Assessment Criteria

Section 5(1) sets out the purpose of the RMA, which is “to promote the sustainable management of natural and physical resources”.

Section 5(2)(c) provides for this to occur while “avoiding, remedying, or mitigating any adverse effects of activities on the environment”.

Section 2 of the RMA defines ‘environment’ and ‘amenity values’ as follows:

“Environment

includes –

(a) ecosystems and their constituent parts, including people and communities; and

(b) all natural and physical resources; and

(c) amenity values; and

(d) the social, economic, aesthetic, and cultural conditions which affect the matters stated in paragraphs (a) to (c) of this definition or which are affected by those matters.

Amenity values

Those natural or physical qualities and characteristics of an area that contribute to people’s appreciation of its pleasantness, aesthetic coherence, and cultural and recreational attributes.”

Offensive odours can be considered to cause effects on amenity values, people and communities and as such need to be managed in accordance with the RMA. Since the compounds that cause odour effects are airborne contaminants, their discharge is therefore controlled under section 15 of the RMA. Under section 15(1) of the RMA, discharges from industrial or trade premises are only allowed if they are authorised by a rule in a regional plan, a resource consent, or regulations. If the activity is prohibited under the plan, then no resource consent can be obtained.

3.2 Regional Assessment Criteria

The project site falls under the jurisdiction of the Waikato Regional Council (WRC).

3.2.1 Waikato Regional Plan

Rule 6.1.15 of the WRP relates to the implementation methods for discharges to air from poultry farming. After an assessment of the activities relating to the proposed expansion, it was determined that consent is required under restricted discretionary activity Rule 6.1.15.3. This is due to the discharge not complying with Rules 6.1.15.1 (intensive farms other than chickens, pigs or mushrooms) and 6.1.15.2 (intensive farming established before the WRP became operative).

The rules contained in the WRP that are relevant to this project are as follows:

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6.1.15.3 Restricted Discretionary Activity Rule – Discharges from Intensive Indoor Farms

Unless provided for by Rules 6.1.15.1 and 6.1.15.2 the discharge of contaminants into air from buildings associated with intensive indoor farms, is a restricted discretionary activity (requiring resource consent).

Waikato Regional Council will reserve discretion on the following matters:

i. Location of the buildings on the site, relative to prevailing winds, climatic conditions and neighbouring properties.

ii. Emission control equipment. iii. Information and monitoring requirements. iv. Visual or nuisance effects on neighbours. v. Application of Best Practicable Option. vi. Measures to avoid, remedy or mitigate the adverse effects on neighbouring dwelling places or

properties. vii. Measures to avoid, remedy or mitigate the adverse effects of contaminants on neighbouring

dwelling places or properties. viii. Contents of a management plan.

The WRP also sets out in Section 6.4.1 an assessment methodology for odour. When assessing a resource consent application, the WRC will consider one or more of the following types of information:

a. History of complaints regarding the discharge. b. Experiences of Waikato Regional Council with the discharge and information held by this

Council or a territorial authority regarding past compliance. c. Information from community consultation undertaken by the discharger. d. Information from odour diaries, odour annoyance surveys or other community surveys

undertaken by the discharger. e. Dynamic dilution olfactometry measurements, population annoyance surveys where the

population sampled is of sufficient size to provide statistically significant results and dispersion modelling results.

f. Whether the best practicable option is being applied for the discharge. g. Records of emission control improvements undertaken and those improvements proposed for

the future. h. Past experiences and knowledge of Waikato Regional Council of the odour effects generated

form existing sites of a similar nature and scale. i. Other information as justified on a case-by-case basis.

Based on the guidelines set out in Section 6.4.1 of the WRP, AECOM considers that a FIDOL assessment is best used for the application of the proposed expansion of Massey Farms.

3.2.2 Separation distances and WRC determination of notification

In the Application two distances were considered, 500 m and 1,000 m, and were used to provide some guidance on the area within which neighbours should be notified about the proposal to increase the farm size. The distances used have been based on two Australian guidance documents, both of which now appear to have been superseded.

The majority of these values are calculated using formulas which consider a number of variables associated with the farms and local terrain, and are ultimately based on a combination of atmospheric dispersion modelling studies and experience, with the simplified formula intended to provide conservative separation distances.

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AECOM has looked at these separation distances on a number of occasions and consider that there are significant issues using them, and that they have the potential to significantly over-predict the distances within which any form of odour effect can be experienced.

Table 1 has set out the separation distances set by various Australian guidance documents.

Table 1 Australian State Chicken Farm Separation Distances

State Separation Distance (m)

New South Wales 1,9251

Queensland 1,0912

South Australia 250

Tasmania 500

Victoria 6383

Western Australian 300 -1000

These separation distances have primarily been developed to provide default minimum separation from activities to sensitive receptors such as residences. They do not make any allowance for the level of control or management that may exist, although most of the documents indicate that distances can be reduced where a more detailed assessment is undertaken.

Based on the work that AECOM have carried on chicken farms there are a numerous factors that influence the level of odour that might be generated. Of these the four that appear to have the greatest influence are ambient temperature; bird stocking density; used litter control and farm management.

Firstly ambient temperature. Broiler sheds are maintained at specific fixed temperatures across that growing cycle, starting at about 30°C and reducing to approximately 20°C. Initially the sheds are heated, but as the birds mature they generate heat which needs to be removed. Typically temperature is controlled by fans which draw ambient air through the sheds. In Australia, particularly in summer, ambient temperatures are significantly greater than 20°C therefore to achieve a cooling effect, significant volumes of air need to be drawn through the sheds. This means that more fans need to operate to maintain the temperature. This creates greater potential for an odour discharge, and as these climatic conditions also tend to coincide with low dispersive atmospheric conditions, the odour plumes tend to remain very coherent and can be detectable for a significant distance from the source.

Consequently this means that any formula that have been developed based on effects in these conditions significantly over estimates the potential for odours in New Zealand and consequently the separation distance required to avoid any nuisance effects.

The second factor that influences odour potential is bird stocking density. There is a reasonably direct correlation between the number of birds in a shed and the level of odour produced. This means that farms that operate at lower stocking densities than broilers such as brooder or rearer farms have virtually no issues with odour. A lot of the work on developing the separation distance guidance occurred a number of years ago when stocking densities were higher, and in New Zealand there has been a consistent move over the past few years to reduce the stocking densities. The maximum density for broiler chickens in the current Australian Code of Practice for Poultry

4 is 40 kg/m² whereas

the current legal maximum in New Zealand is 38 kg/m², with most farms being stocked at lower rates than this. This means that any odour emissions, and separation distances calculated using the Australian guidance based on higher stocking density will overestimate appropriate separation distances for New Zealand farms.

1 Based on New South Wales Level 1 Odour Assessment Calculator and 360,000 birds

2 Based on calculation in Development if Meat Chicken Farms in Queensland, July 2016 and a maximum of 300,000 birds

formula and 3 Based on the Formula D= 27 x N

0.54 and 360,000 birds

4 Model Code of Practice for the Welfare of Animals Domestic Poultry, 4

th Edition 2002

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The third factor variable is the management of spent litter. AECOM understands that it is relativelycommon in Australia for spent litter from the sheds to be left on site for a number of days, before eitherbeing composted or removed, with composted material often spread on the land around the farm.This activity, and the storage of litter can generate odour, and some of the separation distanceguidelines make an allowance for this. In New Zealand the practice is to remove the litter from site asthe sheds are cleaned out at the end of a cycle. This means that any separation distances which haveincluded allowance for the storage and composting of this material are overly conservative.

The final factor is site management. One of the purposes of separation distances is to allow for poorsite management practices. The implications of this are discussed in the following section as ourexperience is that it is typically only when there are poor management practices that odour issuesoccur.

3.2.2.1 New Zealand Poultry ResearchAECOM was engaged by the Poultry Industry Association New Zealand (PIANZ) to prepare a reportthat looked at the level of complaints that occurred for all forms of chicken farms. This researchindicated that over 80 percent of all chicken farms received no complaints over the 10 year periodreviewed. When the data was just analysed for broiler farms the percentage of sites with nocomplaints is 73% percent, with the majority of sites receiving less than 5 complaints over the 10 yearperiod.

One of the factors that AECOM investigated was whether there was any correlation between thecomplaints and how close the nearest neighbour was to the farm. Our investigation concluded thatthere was no correlation and no greater likelihood that a broiler farm with neighbours within 200 mwould receive complaints that one whose nearest neighbour was more than 200 m away. Given thatthe majority (83%) of broiler farms have neighbours within 200 m there appears no justification forhaving distances greater than this.

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4.0 Assessment Methodology

4.1 Qualitative Assessment Methodology (FIDOL)

Complaints are likely to occur when odours become detectable and recognisable. However, there are many situations when the release of a potentially odorous compound does not result in an odour nuisance effect. It is the subjective judgement of an odour's hedonic tone that enables the decision to be made as to whether it is a nuisance or not. The factors that contribute to an odour nuisance effect include the frequency (F) of odour impact, the intensity (I), the duration of exposure (D), the offensiveness (O) and the location (L). This type of assessment is similar to the guideline for assessing odour in the RAQP.

The FIDOL factors are explained in greater detail below:

Frequency; relates to how often an individual is exposed to odour. Factors determining this include the frequency that the source releases odour (including its source type, characteristics and the rate of emission of the compound or compounds); prevailing meteorological conditions; and topography.

Intensity: is the perceived strength of the odour or the odour detection capacity of individuals to the various compound(s). An increase in intensity of odour will increase the potential for odour complaints. Subjective measurements are made on a scale of 1 to 6 and qualitative measurements are in odour units (OU or OU/m³).

Duration: is the amount of time that an individual is exposed to odour. Combined with frequency, this indicates the exposure to odour. The duration of an odour, like its frequency, is related to the source type and discharge characteristics, meteorology and location. The longer the odour detection persists in an individual location, the greater the level of complaints that may be expected, particularly if the odours are unpleasant or obnoxious.

Offensiveness: is a subjective rating of an odour's pleasantness and relates closely to hedonic tone. Offensiveness is related to the sensitivity of the 'receptors' to the odour emission, i.e. whether the odorous compound is more likely to cause nuisance, such as the sick or elderly, who may be more sensitive.

Location: is the type of land use and the nature of human activities in the vicinity of an odour source. The same process in a different location may produce more or less odour depending on local topography and meteorological conditions. It is also important to note that in some locations certain odours may be more acceptable than in others (e.g. the expectation that rural smells will occur as part of the rural environment and industrial smells will occur in industrial areas).

AECOM has assessed each of these factors to determine if off-site odours are likely to be offensive or objectionable.

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4.2 Sensitive Receptors

In the context of this odour assessment, the term ‘sensitive receptor’ includes any persons, locations or systems that may be susceptible to changes in abiotic factors as a consequence of the discharges to air (namely odour) from the Project Site. Typical locations for sensitive receptors include:

Residential properties;

Retirement villages;

Hospitals or medical centres;

Schools;

Libraries; and,

Public outdoor locations (e.g. parks, reserves, sports fields, beaches).

A desk-study as well as field observations were undertaken to identify discrete receptors deemed sensitive to odour as a result of discharges to air from the proposed. AECOM has not included all of the residential locations as discrete receptors for practical purposes, but has instead selected a number of locations to be representative of them.

The nearest potentially affected sensitive receptors are summarised in Table 2. Figure 2 shows the location of the potentially affected sensitive receptors identified (R1 – R11) in this assessment.

Table 2 Location of Receptors located close to the Project Site

Receptor Name

Address Receptor Type Distance from

the Site (m)

Direction Relative to the

Site

R1 175 Wily Road Residential 1,000 North

R2 173 Wily Road Residential 700 Northeast

R3 229 Wily Road Residential 430 Northeast

R4 15B Shipherd Road Residential 870 East northeast

R5 256 Aka Aka Road Residential 890 East

R6 254 Aka Aka Road Residential 1,000 East

R7 324 Aka Aka Road Residential 430 East

R8 309 Aka Aka Road Residential 630 Southeast

R9 27 Massey Road Residential 590 South southeast

R10 69 Massey Road Residential 450 South

R11 99A Massey Road Residential 540 West southwest

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Figure 2 Sensitive Receptor Locations

4.3 Field Odour Investigation

Subjective field odour investigations (or odour survey) were carried out at the existing farm when birds were 14, 28 and 42 days old, and during a shed clean out, by an odour assessor using the FIDOL factors to determine an odour impact rating for several different locations across the site and beyond the site boundary. These dates where chosen as they would give the best representation of what odours might be observed from the proposed new farm across the entire growing period. The investigations were carried out in accordance with the guidance contained in Ministry for the Environment (MfE) Good Practice Guide for Assessing and Managing Odour

5 (MfE GPG Odour). The

primary purpose of undertaking this survey was to understand the level of odour from the current farming operations. The findings of this odour survey are presented in Section 5.3.

4.4 Wind Speed and Wind Direction

The nearest Automated Weather Station (AWS) that AECOM could obtain validated data, relative to the Project Site is located at Pukekohe, approximately 6 km north-northeast of the Project Site. The AWS is operated by the National Institute of Water and Atmospheric Research (NIWA). The AWS is located at UTM 310,440 mE 5,880,290 mN.

Analysis of hourly wind data for the Pukekohe AWS for the five-year period 1 January 2013 and 31 December 2017 indicates that winds from all directions are experienced at the AWS site, however, the predominant winds are from the south southwest and west southwest. The data capture during this monitoring period was excellent at 99%.

5 MfE Good Practice Guide for Assessing and Managing Odour, November 2016

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The wind rose for the Pukekohe AWS for the period 1 January 2013 and 31 December 2017 is presented in Figure 3, yearly windroses in Figure 4, and seasonal wind roses are presented in Figure 5. Figure 4 shows that there was relatively little inter-annual variation in wind direction.

The seasonal wind roses indicate that:

In summer, the prevailing wind directions are from the south southwest.

In autumn, the prevailing wind direction is from the southwest and east southwest.

In winter, the prevailing wind directions are from the southwest and east southwest.

In spring, the prevailing wind directions are from the southwest and west southwest.

Table 3 presents the distribution frequency of wind speed. The predominant lower speed winds (less than 3 m/s) originate from the southwest and the east southeast , with calms (winds less than 0.5 m/s) occurring 3.8 percent of the time. Based on AECOM’s experience, it is these light wind conditions which have the greatest potential to cause odour nuisance effects due to reduction in the dispersion and dilution of the odour emissions.

Table 3 Wind Speed Frequency Distribution

Direction Wind Speed (m/s)

Total (%) 0 - 3 >3

North 3.4 1.4 4.8

North northeast 4.5 3.5 8.0

Northeast 3.5 1.3 4.9

East northeast 3.4 1.0 4.4

East 4.2 1.3 5.5

East southeast 6.9 1.8 8.7

Southeast 4.2 0.7 4.9

South southeast 2.8 0.3 3.1

South 2.6 0.3 2.9

South southwest 3.0 0.7 3.7

South west 6.0 8.7 14.7

West southwest 4.6 6.3 10.9

West 3.1 4.1 7.2

West northwest 2.3 2.7 5.0

Northwest 2.1 1.5 3.5

North northwest 2.0 0.8 2.8

It is noted that due to the local topography there may be a greater percentage of lower wind speeds from the northeast than is present in the Pukekohe data.

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Figure 3 Pukekohe AWS Windrose – January 2013 to December 2017

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Figure 4 Pukekohe AWS Yearly Windrose – January 2013 to December 2017

2013 2014 2015

2016 2017

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Figure 5 Pukekohe AWS Seasonal Windroses – January 2013 to December 2017

Spring Summer

Autumn Winter

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5.0 Odour Assessment

5.1 Methodology

The ambient odour monitoring methodology utilised in this study is a variation of the method described in the German Standard Verein Deutscher Ingenieure (VDI) 3940 “Determination of Odorants in Ambient Air by Field Inspections” (VDI Method). This is the method recommended in the Ministry for the Environment (MFE) Good Practice Guide for Assessing and Managing Odour in New Zealand and is commonly used in Australia and Europe for odour assessment.

5.2 Sampling

The modified method used by AECOM involved using a single ‘field odour scout’ to visit a selection of sites and sample the ambient air every 10 seconds for 10 minutes giving a total of 60 samples per location per day. The field odour scout recorded the intensity of the odour (according to a set intensity scale), the odour character (from a list of 40 various odour descriptors), the wind direction, the wind speed, any rainfall, and the time and date for every sample. The wind direction was determined and recorded by the field odour scout using a compass. Wind speed was recorded using a Kestrel handheld weather meter.

5.3 Field Odour Investigation

5.3.1 Two Weeks After Placement (4 December 2017)

AECOM staff arrived onsite at approximately 10:00 am, and during the observations the birds were 14 days old. The weather conditions during the site visit were dry, partly overcast, with very light to light winds (0.6 and 2.4 m/s) originating from the southwest. AECOM undertook the odour survey at Locations 1 to 8, as shown in Figure 6, between 10:30 am and 12:30 pm.

5.3.1.1 Field odour Investigation Locations (4 December 2017)

The field odour investigation was carried out at various upwind and downwind locations on or beyond the site boundary:

- Location 1: Corner of Aka Aka and Massey Road;

- Location 2: 254 Aka Aka Road;

- Location 3: Corner of Shipherd Road and Aka Aka Road;

- Location 4: Upwind of Sheds;

- Location 5: Northwest of Shed 1 (5 metres from shed);

- Location 6: Downwind of Sheds 1 and 2 (5 metres from fans);

- Location 7: Downwind of farm Shed 4 (5 metres from fans), and;

- Location 8: Downwind of Farm (25 metres from fans).

5.3.2 Four Weeks After Placement (18 December 2017)

AECOM staff arrived onsite at approximately 09:20 am, and during the observations the birds were 28 days old. The weather conditions during the site visit were dry, sunny, with calm to light winds (0.2 and 3.1 m/s) originating from the southwest. AECOM undertook the odour survey at Locations 1 to 8, as shown in Figure 6, between 09:30 am and 11:20 am.

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5.3.2.1 Field odour Investigation Locations (18 December 2017)


- Location 1: Corner of Aka Aka and Massey Road;

- Location 2: 254 Aka Aka Road;

- Location 3: Corner of Shipherd Road and Aka Aka Road;

- Location 4: Upwind of Sheds;

- Location 5: Northwest of Shed 1 (5 metres from shed);

- Location 6: Downwind of Sheds 1 and 2 (5 metres from fans);

- Location 7: Downwind of farm Shed 4 (5 metres from fans), and;

- Location 8: Downwind of Farm (25 metres from fans).

Figure 6 Odour Survey Locations (4 and 18 December 2018)

Wind Direction

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5.3.3 Six Weeks after Placement (28 February 2018)

AECOM staff arrived onsite at approximately 07:45 am. During the time of the observations the birds were at 42 days old, and all the remaining birds in shed one were being harvested. The weather conditions during the site visit were dry, partly overcast, with calm to gentle breeze (0 and 4 m/s) originating from the east to northeast.

The odour investigation was undertaken by AECOM staff, as well as representatives from Waikato Regional Council, Waikato District Council and the submitters, at Locations 1 to 5, as shown in Figure 7, between 08:20 am and 10:30 am.

5.3.3.1 Field odour Investigation Locations (28 February 2018)


- Location 1: 366 Wily Road;

- Location 2: 277 Wily Road;

- Location 3: Potato Paddock (350 metres from farm);

- Location 4: Entrance to Potato Paddock (250 metres from farm), and;

- Location 5: Downwind of Farm (50 metres from farm).

Figure 7 Odour Survey Locations (28 February 2018)

Wind Direction

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5.3.4 Harvest and Shed Clean-out (5 March 2018)

AECOM staff arrived onsite at approximately 09:00 am. During the observations the Shed 3 was being cleaned out and the remaining birds were getting harvested from Shed 4. The weather conditions during the site visit were dry, partly overcast, with calm to very light winds (0 and 0.8 m/s) originating from the east to south. The wind speeds at the sites were between.

The odour investigation was undertaken by AECOM staff and a representative from the Waikato Regional Council also attend the site. The odour survey was undertaken at Locations 1 to 6, as shown in Figure 8, between 10:00 am and 11:50 am.

5.3.4.1 Field odour Investigation Locations (5 March 2018)


- Location 1: Driveway (50 metres from farm);

- Location 2: Shed 1;



- Location 5: Downwind of Sheds 2 and 3 (30 metres);

- Location 6: Downwind of Sheds 2 and 3 (50 metres).

Figure 8 Odour Survey Locations (5 March 2018)

Wind Direction

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5.3.5 Field Odour Investigation Findings (4 December 2017)

Where odour associated with chicken farming was detectable the odour was classified as “very weak” to “distinct” and having a chicken manure odour character (neutral to slightly unpleasant). Odour associated with chicken farming was only ever detected downwind of the farm and the strongest odours were directly adjacent to the fan outlets. However once away from the fan the odour was very weak in intensity. As experienced with other chicken farms at this stage in the process, the odour became weaker and transient in nature the further the distance from the farm, and chicken farm odours were not detected more than 50 metres from the exhaust fans of the sheds.

No objectionable or offensive odours were detected at any off-site location around the site. Overall, the odour from the farms on the day of testing was low and consistent with the level of odour expected from this type of chicken operation, at this stage in the cycle, and what AECOM has experienced on other farms.

Description of Odours Experienced

The odour described by the assessor at locations 1 – 8 was as follows:

- Location 1: Corner of Aka Aka and Massey Road: Very Weak Earth and Vegetation Odour.

- Location 2: 254 Aka Aka Road: Very Weak Vegetation Odour.

- Location 3: Corner of Shipherd Road and Aka Aka Road: Very Weak Vegetation Odour.

- Location 4: Upwind of Sheds: Very Weak Earth and Chicken Manure Odour.

- Location 5: Northwest of Shed 1 (5 metres): Very Weak/ Weak Chicken Manure Odour.

- Location 6: Downwind of Sheds 1 and 2 (5 metres): Very Weak/Distinct Chicken Manure Odour.

- Location 7: Downwind of farm Shed 4 (5 metres): Very Weak/Distinct Chicken Manure Odour.

- Location 8: Downwind of Farm (25 metres). Very Weak/Distinct Chicken Manure Odour.

5.3.6 Field Odour Investigation Findings (18 December 2017)

Where odour associated with chicken farming was detectable the odour was classified as “very weak” to “distinct” and having a chicken manure odour character (neutral to slightly unpleasant). Odour associated with chicken farming was only ever detected downwind of the farm and the strongest odours were directly adjacent to the fan outlets. However once away from the fan the odour was very weak in intensity. As experienced with other chicken farms at this stage in the process, the odour became weaker and transient in nature the further the distance from the farm, and chicken farm odours were not detected more than 50 metres from the exhaust fans of the sheds.




- Location 1: Corner of Aka Aka and Massey Road: Very Weak Vegetation Odour.

- Location 2: 254 Aka Aka Road: Very Weak Vegetation Odour.

- Location 3: Corner of Shipherd Road and Aka Aka Road: Very Weak Vegetation Odour.

- Location 4: Upwind of Sheds: Very Weak Earth Odour.

- Location 5: Northwest of Shed 1 (5 metres): Very Weak Chicken Manure Odour.

- Location 6: Downwind of Sheds 1 and 2 (5 metres): Very Weak/Distinct Chicken Manure Odour.

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- Location 7: Downwind of farm Shed 4 (5 metres): Very Weak/Distinct Chicken Manure Odour.

- Location 8: Downwind of Farm (25 metres). Very Weak/Weak Chicken Manure Odour.

5.3.7 Field Odour Investigation Findings (28 February 2018)

Where odour associated with chicken farming was detectable the odour was classified as “very weak” to “strong” and having a chicken and manure type odour character (neutral to slightly unpleasant). Odour associated with chicken farming was only ever detected downwind of the farm. During the harvesting of birds, odours from the manure and the birds were just able to be identified 350 metres downwind of the farm. During the observations the odour became weaker and transient in nature the further the distance from the farm.

Observing chicken type odours, albeit distinct but not offensive, up to 350 metres from the farm (Location 3) is not typical based on the many farms AECOM has observed. AECOM considers that the odour observations up to 350 metres on the day was a result of strong wind tunnelling through the open doors of the shed and filtering through the stacked birds waiting to be transported. It is AECOM’s opinion if the winds were in another direction, i.e. not parallel to the shed, that odour would not have been observed nearly as far from the sheds. During odour observations on 5 March 2018, when similar operations were taken place, the wind was at a 45 degree angle to the sheds and odour was not observed more than 50 metres from the sheds.



- Location 1: 366 Wily Road: Very Weak Vegetation Odour.

- Location 2: 277 Wily Road: Very Weak Chicken Manure and Very Weak/Distinct Onion Odour.

- Location 3: Potato Paddock: Very Weak/Distinct Chicken Manure and Very Weak/Weak Chemical Odour.

- Location 4: Entrance to Potato Paddock (250 metres from farm): Very Weak Chicken and Manure and Very Weak/Distinct Compost Odour.

- Location 5: Downwind of Farm (50 metres from farm): Very Weak/Strong Chicken and Manure Odour.

5.3.8 Field Odour Investigation Findings (5 March 2018)

Where odour associated with chicken farming was detectable the odour was classified as “very weak” to “distinct” and having a chicken manure odour character (neutral to slightly unpleasant). Odour associated with chicken farming was only ever detected downwind of the farm and the strongest odours were directly adjacent to the fan outlets. However once away from the fan the odour was very weak in intensity. As experienced with other chicken farms at this stage in the process, the odour became weaker and transient in nature the further the distance from the farm, and chicken farm odours were not detected more than 50 m from the exhaust fans of the sheds.


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- Location 1: Driveway (50 metres from farm): No discernible Odour.

- Location 2: Shed 1: Very Weak/Weak Chicken Manure Odour.

- Location 3: Shed 2: Very Weak/Distinct Chicken Manure Odour.

- Location 4: Shed 3: Very Weak/Distinct Chicken Manure Odour.

- Location 5: Downwind of Sheds 2 and 3 (30 metres): Very Weak Vegetation Odour.

- Location 6: Downwind of Sheds 2 and 3 (50 metres): No discernible Odour.

5.3.9 Overall Findings

Overall when odour associated with chicken farming was detected, the odour was typically classified as “very weak” to “distinct” and was characterised as a chicken manure type odour. Odours related to chicken farming were only detected downwind of the farm (excepted when standing within five metres of the fan). Odour from the farm was only detected once at an off-site location, and it was classified as a “very weak” and only last for 10 to 20 seconds. Typically the odour from the site became weaker and transient in nature the further the distance from the farm, and chicken farm odours were generally not detected more than 50 metres from the exhaust fans of the sheds.

Based on the odour observations and AECOM has experienced on other farms, odour levels are typically lower during the earlier periods in the cycle and tend to increase as the birds increase in age. Typically harvesting of the birds generates an increase amount of odour as well as shed clean-out, due to the disturbance of the chicken litter. Based on the odour observations at Massey Farm during harvesting, odour was detected 350 metres from the sheds. Based on AECOM’s experience this is unusual and further investigation tended to indicate this was caused by strong north-easterly winds tunnelling through the shed and filtering through the caged and stacked birds ready for transporting. To mitigate against this unusual event, AECOM would recommend either one or all of the following mitigation measures:

Avoid as far as practicable having the northern doors open when catching birds and when winds are coming from the northeast.

Plant shelter belts to northwest of the sheds to provide some protection.

As far as practicable park trucks away from the entrance of the shed when both doors are open and the winds are coming from the northeast.

5.4 Odour Assessment

It is generally accepted that odours associated with chicken farming are considered unpleasant by the general population, and therefore odour from the proposed activities needs to be appropriately controlled.

However it is AECOM’s experience that even with all appropriate mitigation measures in place there is the potential that from time to time odours may be detectable off-site. Consequently, AECOM considers that it is appropriate to use the FIDOL assessment tool to determine whether the odours have the potential to be offensive and objectionable.

This assessment has been based on the new farm being an indoor grower and the use of the mitigation measures presented in Section 2.2.2 and Section 5.3.9. However the intention is use the new sheds for free range farming, and therefore there should be further reductions in odour emissions over those that occur from a totally indoor operation.

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5.4.1 Frequency

Frequency relates to how often odours will be experienced at an off-site receptor. In terms of odour from the proposed farm, odour concentrations emitted by the farm will be variable, throughout the growing cycle. Therefore the frequency at which odour could be detected at the neighbouring property will be a combination of the odour emission rate from the farm and certain meteorological conditions, such as those which produce poor dispersion conditions.

The proposed new sheds will work on the same seven week cycle, with birds being placed at one day old. During the first 11 days the shed temperature is kept elevated, and only the minimum number of fans (between 1-3) are used for ventilation. The temperature is gradually reduced to 20°C from day 11 to day 26, with generally only 2-3 fans operating. Bird mass peaks at day 31 when the first harvest occurs which usually reduces the bird numbers by half. From day 31 through the final day (day 42) there is typically another one to two more cuts depending on production requirements, and therefore this reduction in bird numbers would correspond to a reduction in odour emissions, as the amount of fans required to maintain the shed temperature is less. It is only when ambient temperatures are over 25°C and the birds are approaching the end of the cycle that most of the fans are likely to operate.

Following the final harvest the shed litter is removed immediately from site by contractors, and the shed are cleaned and disinfected over the next seven to ten days in preparation for the next batch of birds. It has often been mentioned that the shed clean out can be an odorous process, however AECOM has undertaken numerous odour observations during this process from many different farms around the country, and have not observed any noticeable increase in odour during this event.

Based on the seven week bird cycle, there only six to seven production cycles per year. As already mentioned odour emissions during the bird cycle is variable, with periods of time where there is minimal odour emissions. For odours to be experienced off-site these peak odour events have to occur during periods of poor dispersion, typically when wind speeds are below 3 m/s. Based on the meteorological data presented in Section 4, when considering the closest receptors that have not provided written consent; 229 Wily Road, 324 Aka Aka Road, and 99A Massey Road, these properties would only be downwind of the site when wind speeds are less than 3 m/s less than 4.6 percent of the time. Considering the variability of odour emissions from the proposed farm and the likelihood of poor dispersion conditions in the direction of the closest receptors occurring at the same time are low.

5.4.2 Intensity

Odour associated with chicken farming can have a strong intensity and can be considered offensive and objectionable by some people. However based on AECOM’s experience odours with this intensity are usually only detectable within 10 to 20 metres of the discharge fans, and have rarely experience offensive or objectionable odour more than 50 metres from a chicken farm.

However based on the observations undertaken at Massey Farm when all sheds had birds around 42 days old and there was harvesting occurring, chicken odours where experienced intermittently out to 350 metre from the sheds and these odours were very weak to distinct in intensity and were not deemed to be offensive. Closer to the sheds the odour increases in intensity and at around 80 metres from the sheds there was odour associated with the chicken farm that was described as strong and would likely be considered offensive if it was experienced off-site.

As discussed earlier the increase in bird numbers particularly with free range birds should not significantly increase the intensity of odours. This is due to the human perception of odour intensity in relation to odour concentration is not a linear relationship but logarithmic. This means that a 10 fold increase in odour concentration will not result in a perceived increase in odour intensity of the same amount

6, with the perceived increase in odour intensity being much less than the numerical increase in

odour concentration. It is generally considered that odour concentrations need to double before the perceived intensity change is recognisable.

The intensity is also related to the wind conditions and the resulting level of dilution that occurs between the source and the receptor. In essence, the stronger the wind, the more dilution of odour will occur. Considering the distance of the site to the receptors, odour from the farm should be well diluted before it reaches residential dwellings.

6 MfE Good Practise Guide for Assessing and Managing Odour in New Zealand (2003)

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For the majority of the time any odours that are generated are expected to be very weak at or beyond the site boundary.

5.4.3 Duration

As discussed previously, there will likely be some odour associated with the chicken farm once the birds are more than one week old, however these, generally have very low intensity and are only detectable onsite or very close to the sheds.

As with frequency, the duration that anyone would be exposed to odour depends on the time the wind blows in a specific direction along with the duration that the activities occur. As discussed in Section 5.4.1 the farm will have up to seven cycles per year and each cycle will last seven weeks. Odour emissions during the cycle are quite variable, and is dependent on many factors such as bird age, stocking density, ambient temperature and litter control.

Typically the duration odour experienced off-site under normal day to day running of the farm is short and intermittent. This is due to the exhaust fans switching on and off in order to maintain a suitable environment for the birds. However during other parts of the process such as catching and clean-out, which can take a number of hours to complete the duration of the odour event could be for extended periods. Fan operation is also further influenced by ambient temperature. In winter when ambient temperatures are low, there would be little to no ventilation occurring, regardless of the birds age. This period of low fan use typically coincides with poor dispersion conditions that are often experienced in North Waikato.

However the catching and clean out activities will be longer in duration, as catching typically starts during the early hours of the morning and the clean out is usually completed by midday. Typically the catching is the more odorous and due to the early start it is less likely that people will be around to experience the odours from the catching event in its entirety.

If the news sheds were to be used for free range operations the growing cycle will most likely be out of sync with the original indoor growing operations. However as the odour from free range operations is low, this increase in duration will be less noticeable. Alternatively if the news sheds were to be operated for indoor growing, all sheds will most likely operate on a synchronised cycle and therefore should not be an increase in the duration of the maximum odour discharges

5.4.4 Offensiveness

If strong undiluted odours associated with chicken farming were experienced off-site, they would be generally considered offensive by a member of the public. As the site is surrounded by rural activities, and the closest receptors are greater than 500 meters away, typically any odours should be well diluted by the time they could reach any receptor, and therefore are unlikely to be considered offensive. Additionally the land directly downwind of the predominant wind directions is rural pasture, and therefore it is not unusual to smell dairy or silage type odours in that area.

If the proposed new sheds were to be used for free range operations the level of offensive odours will be reduced, as there will be less odour when birds are outside.

5.4.5 Location

To a large extent the location of the source in proximity to sensitive receptors is possibly the most important of the FIDOL factors. In this instance due to the fact that even if odours are generated there is little potential for adverse effect if there are few receptors located downwind of the source.

In this case, AECOM considers that the location of the site is well placed in terms of the distance to nearby receptors being greater than 500 metres away.

The Massey Road farm is located in a remote rural area, and the MfE GPG for odour recommends that there is a greater tolerance of odour effects in a rural setting, particularly when the source of the odour is from a rural activity. It is not unusual to experience a degree of rural type odour such as silage and manure in the surrounding area which is considered acceptable.

Additionally the location of the farm has some unique topography, with the farm itself located near the bottom of a valley and the land further to the northeast rising to a bluff. Other than the terrain there is relatively few natural features such as large vegetation that may influence wind direction. Even when considering the terrain, AECOM considers this would have little influence on the wind direction. In

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certain wind conditions the wind would follow the topography of the land, but would not alter the wind direction in its entirety.

Furthermore there are other chicken farms of the similar size to that of Massey Farms in the surrounding area. These farms are typically between 2,000 to 4,000 metres from Massey Farm, and based on these distances there is very little possibility of these farms creating a cumulative effect with Massey Farm. The closest farm is 1,200 metres to the southeast, however this is an indoor breeder and based on stocking density of breeder it is unlikely there would be any significant odour from this farm to cause a cumulative effect. Even if there was enough odour generated that could be detected more than 1,200 metres from the farm, winds from the right direction to cause a cumulative effect with Massey Farm only occur 4.2 percent of the time, with no dwellings downwind of Massey Farm in this direction.

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6.0 Conclusion

Having assessed the odour results against the FIDOL factors, AECOM considers that there is a low likelihood of off-site odour from the proposed expanded chicken farm being categorised as objectionable and offensive at nearby receptor locations. This is based on the following factors:

When the birds are young, there is very little ventilation in order to maintain an optimal environment. As the ventilation minimal, therefore the emission rate is also low.

From day 31 the bird numbers are reduced, and by the end of the cycle at day 42 only around 25 percent of the original bird numbers might be present. As odour emissions are related to bird numbers this reduction in bird number will decrease the amount of odour generated.

Based on the meteorological data for the area, the closest receptors would only be downwind of the site when wind speeds are less than 3 m/s less than 4.6 percent of the time. Based on the varied emission rate from the farm there is a low probability of higher odour emission rates occurring at the same time as poor dispersive conditions.

There is a large separation distance between the proposed farm, and the closest sensitive receptors, with the closest dwellings being greater than 500 metres from the closest shed. This large separation distance will help dilute any odour that might be generated by the farm.

The surrounding land has a rural zone, therefore it is not unusual to experience rural type odours such as silage and manure. Additionally due the rural environment there is relatively few sensitive receptors in the surrounding the proposed farm.

However the most significant factor in reducing odour emissions from the proposed new farm layout is that if the birds for the new sheds are free range, and therefore excretion is not always confined to inside the sheds, and therefore there is less build-up in the litter during the growing cycle of high odour waste.

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7.0 Limitations

AECOM New Zealand Limited (AECOM) has prepared this Assessment of Odour Effects report in accordance

with the usual care and thoroughness of the consulting profession for Massey Farm Limited for use in a statutory

process from the Waikato Regional Council under the Resource Management Act 1991 (RMA) for activities to be

undertaken at 98 Massey Road, Aka Aka.

Except as specifically stated in this section, AECOM does not authorise the use of this Report by any third party

except as provided for by the RMA.

It is based on generally accepted practices and standards at the time it was prepared. No other warranty,

expressed or implied, is made as to the professional advice included in this Report.

It is prepared in accordance with the scope of work and for the purpose outlined in the contract dated 9 November

2017.

Where this Report indicates that information has been provided to AECOM by third parties, AECOM has made no

independent verification of this information except as expressly stated in this Report. AECOM assumes no liability

for any inaccuracies in or omissions to that information.

This Report was prepared in March and April 2018 and is based on the conditions encountered and information

reviewed at the time of preparation. AECOM disclaims responsibility for any changes that may have occurred

after this time.

This Report should be read in full. No responsibility is accepted for use of any part of this Report in any other

context or for any other purpose than that stated above. This Report does not purport to give legal advice. Legal

advice can only be given by qualified legal practitioners.

To the extent permitted by law, AECOM expressly disclaims and excludes liability for any loss, damage, cost or

expenses suffered by any third party using this report for any purpose other than that stated above. AECOM does

not admit that any action, liability or claim may exist or be available to any third party.

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