Volume 1: Sustainability Appraisal of the Maidstone Gypsy, Traveller and Travelling Showpeople Development Plan Document 2023–2040

2 Assessment methodology and scope of appraisal

2.1 The SA Framework

2.1.1 Each of the reasonable alternative sites and policies appraised in this report have been assessed for their likely impacts on each SA Objective of the SA Framework.

2.1.2 The SA Framework is comprised of SA Objectives and decision-making criteria. Acting as yardsticks of sustainability performance, the SA Objectives are designed to represent the topics identified in Schedule 2 of the SEA Regulations²⁵. Including the SEA topics in the SA Objectives helps to ensure that all of the environmental criteria of the SEA Regulations are represented. Consequently, the SA Objectives reflect all subject areas to ensure that the assessment process is transparent, robust and thorough.

2.1.3 The SA Framework is presented in its entirety in Appendix A of this report and is comprised of 13 SA Objectives. Table 2.1 summarises the SA Objectives and their relevance to the SEA themes.

2.1.4 Each SA Objective is considered when appraising sites, policies and reasonable alternatives.

2.1.5 The order of SA Objectives in the SA Framework does not infer prioritisation.

2.1.6 The SA Objectives are at a strategic level and can potentially be open-ended. In order to focus each objective, decision making criteria are presented in the SA Framework to be used during the appraisal of policies and sites.

Table 2.1: Summary of the SA Objectives

2.2 Appraisal process

2.2.1 The purpose of this document is to provide an appraisal of the DPD including reasonable alternatives in line with Regulation 12 of the SEA Regulations²⁶ which states that:

2.2.2 "Where an environmental assessment is required by any provision of Part 2 of these Regulations, the responsible authority shall prepare, or secure the preparation of, an environmental report … [which] shall identify, describe and evaluate the likely significant effects on the environment of implementing the plan or programme, and reasonable alternatives taking into account the objectives and the geographical scope of the plan or programme".

2.3 Impact assessment and determination of significance

2.3.1 Significance of effect is a combination of the sensitivity of receptors and the magnitude of anticipated impacts. Sensitivity can be expressed in relative terms, based on the principle that the more sensitive the resource, the greater the magnitude of the change, and as compared with the do-nothing comparison, the greater will be the significance of effect.

Sensitivity

2.3.2 Sensitivity has been measured through consideration as to how the receiving environment will be impacted by a plan proposal. This includes assessment of the value and vulnerability of the receiving environment, whether or not environmental quality standards will be exceeded, and, for example, if impacts will affect designated areas or landscapes.

2.3.3 A guide to the range of scales used in determining sensitivity is presented in Table 2.2. For most receptors, sensitivity increases with geographic scale.

Table 2.2: Impact sensitivity

Magnitude

2.3.4 Magnitude relates to the degree of change the receptor will experience, including the probability, duration, frequency and reversibility of the impact. Impact magnitude has been determined on the basis of the susceptibility of a receptor to the type of change that will arise, as well as the value of the affected receptor (see Table 2.3).

Table 2.3: Impact magnitude

2.4 Significant effects

2.4.1 A single value from Table 2.4 has been allocated to each SA Objective for each reasonable alternative. Justification for the classification of the impact for each SA objective is presented in an accompanying narrative assessment text for all reasonable alternatives that have been assessed through the SA process.

2.4.2 The assessment of impacts and subsequent evaluation of significant effects is in accordance with Schedule 2 (6) of the SEA Regulations²⁸, where feasible, which states that the effects should include: "secondary, cumulative, synergistic, short, medium and long-term effects, permanent and temporary effects, positive and negative effects, cumulative and synergistic effects".

Table 2.4: Guide to scoring significant effects

2.4.3 When selecting a single value to best represent the sustainability performance, and to understand the significance of effects in terms of the relevant SA Objective, the precautionary principle²⁹ has been used. This is a worst-case scenario approach; if a positive effect is identified in relation to one criterion (see the second column of the SA Framework in Appendix A) and a negative effect is identified in relation to another criterion within the same SA Objective, the overall impact has been assigned as negative for that objective. It is therefore essential to appreciate that the impacts provide only an indicative summary, and the accompanying assessment text provides a fuller explanation of the sustainability performance of the option.

2.4.4 The assessment considers, on a strategic basis, the degree to which a location can accommodate change without adverse effects on valued or important receptors (identified in the baseline).

2.4.5 Significance of effect has been categorised as minor or major. Table 2.4 sets out the significance matrix and explains the terms used to evaluate each reasonable alternative or proposal against each SA Objective of the SA Framework. The nature of the significant effect can be either positive or negative depending on the type of development and the design and mitigation measures proposed. It is important to note that the assessment scores presented in Table 2.4 are high level indicators. The assessment narrative text should always read alongside the significance scores. Likely impacts are not intended to be summed.

2.4.6 A number of topic-specific methodologies and assumptions have been applied to the appraisal process for reasonable alternative sites against each of the SA Objectives (see Appendix B). These should be borne in mind when considering the assessment findings.

2.5 Limitations of predicting effects

2.5.1 SA/SEA is a tool for predicting potential significant effects. Predicting effects relies on an evidence-based approach and incorporates expert judgement. It is often not possible to state with absolute certainty whether effects will occur, as many impacts are influenced by a range of factors such as the design and the success of mitigation measures.

2.5.2 The assessments in this report are based on the best available information, including information provided to Lepus by the Council and publicly available sources. Every attempt has been made to predict effects as accurately as possible.

2.5.3 SA operates at a strategic level which uses available secondary data for the relevant SA Objective. All reasonable alternatives and preferred options are assessed in the same way using the same method. Sometimes, in the absence of more detailed information, forecasting the potential impacts of development can require making reasonable assumptions based on the best available data and trends. However, all options must be assessed in the same way, and any introduction of site-based detail should be made clear in the SA report as the new data could potentially introduce bias and skew the findings of the assessment process.

2.5.4 The assessment of development proposals is limited in terms of available data resources. For example, up to date ecological surveys and/or landscape and visual impact assessments are not currently available. Additionally, the appraisal of the DPD is limited in its assessment of carbon emissions, including its potential to draw on low- carbon/renewable energy technologies, and greater detail of carbon data would help to better quantify effects. Site-specific masterplans are also not available at this stage. Limitations to reasonable alternative site assessments have been outlined in Appendix B.

2.5.5 All data used is secondary data obtained from the Council or freely available on the internet.