Sustainable Solutions

Sustainable Solutions

Sustainable Solutions

Tim Mitchell: 19 April 2022

Sustainability should be a key driver of any Environmental Consultancy, and this certainly rings true for Omnia. Our aim is to engrain sustainability into our day to day, from the minimisation of our vehicles on the road attending site through to our technical recommendations on our interpretative reports.

Remediation is a key area where a consultative approach can lead to a sustainable solution, achieving a client’s key targets of timeframe and cost whilst keeping environmental impact to a minimum. Migration to a focus on sustainability is a driver in government procurement, as set out in the recent publication of The Construction Playbook published by the Cabinet Office The Construction Playbook – GOV.UK (www.gov.uk). This publication sets out a framework to allow bids to be considered in relation to a number of aspects, including the extent of how sustainable the bid.

Sustainable Solutions for Brownfield Development

Where brownfield redevelopment is involved, engagement with a competent Environmental Consultant can assist clients in demonstrating the use of sustainable approaches in their bid. This can initially be through limiting the requirement for remediation via site specific risk assessment and then progressing to a focus on sustainable remediation via on site and in situ treatment rather than transfer to landfill, but can be extended more broadly to more practical local issues such a focus on local workforce.

reusing soil on site

Reusing Soils on Site

The contaminated land industry has increasingly moved to more sustainable approaches including the use of Materials Management Plans under the CL:AIRE DoWCoP. An MMP allows for soils to be reused on site, which has progressed from the prior near automatic solution of transfer of soils to landfill. We see the impact of landfilling in the environment from a legacy perspective in terms of impacted groundwater and ground gas risk, but also now the real time impact of unsustainable approaches which involve significant vehicle movements for the movement of soils in increasingly urban development areas. Opting for a sustainable approach to keep trucks off the roads gives clearly evident benefits such as reduction in fuel bills and the risk to pedestrians, but also provides less immediately quantitative benefits, such as the minimisation of dust release, emissions to local residential properties, alongside significant savings on carbon releases. It is this change that can add clear benefits to tender bids, and can provide an edge other parties.

The Cost of Sustainability?

Sustainability makes sense on a cost basis too, and good planning can allow an all round advantage to development projects. This link up between cost benefit and sustainability credentials for public sector bids alongside increasingly competitive land acquisition for residential developments means that sustainability is on track to be at the forefront of the development industry. 

Our team of qualified Geo-Environmental Consultants have a proven track record of adding value to a project, having an especially key focus on assisting pre acquisition bids for land transactions. Please get in touch and a member of our team will be able to assist. 

If you’d like Omnia’s help with your project, contact us to speak to one of our team.

Noise Impact Assessments: What are they and why do we need them?

Noise Impact Assessments: What are they and why do we need them?

Noise Impact Assessments: What are they and why do we need them?

Noise can be defined as an unwanted or disturbing sound that affects the health, productivity and well-being of people as well as having an impact on the existing environment including animals. Continual exposure to loud noise could result in high blood pressure, heart disease, sleep disturbances, and stress across all age groups, especially children.

What is a Noise Impact Assessment?

Noise Impact Assessments (NIAs) consist of a series of detailed noise surveys, which are often required for a variety of planning applications. These are requested by Local Planning Authorities (LPA), in particular by Environmental Health Officers (EHOs), in order to establish the environmental noise impacts of existing and proposed developments. An NIA will typically involve an assessment of the existing noise sources and comparison of the predicted noise level generated by the proposed development. NIAs are generally requested by an LPA due to concerns arising from noise exposure to prospective or existing noise sensitive properties.  

Typical focus of NIAs:

  • Transport noise (Road, Rail, and Aircraft) to proposed noise sensitive developments (BS8233:2014);
  • Noise from new fixed plant at existing residential receptors (BS4142:2014);
  • Noise from existing commercial units upon proposed noise sensitive developments (BS4142:2014);
  • Noise due to road traffic generated by the development (Change in Ambient).

Focusing on a BS8233:2014 assessment, the aim is to set out appropriate internal and external noise levels for Bedrooms, Living Rooms, Dining Rooms and Gardens for the day time (07:00 – 23:00) and night time (23:00 – 07:00). It also provides guidance on the design of sound insulation for buildings and methods of achieving appropriate noise reduction for new build dwellings and refurbished dwellings undergoing change of use.

Noise modelling is imperative in the work that we do. Noise models are created, through using state of the art CadnaA software, which can accurately predict noise levels, and how they propagate over a site. Figure 1 demonstrates how, through the use of colours and bands, we can effectively demonstrate to clients the feasibility of a site, which is an integral part of a Noise Constraints Assessment. Noise Constraint Assessments are often used at the infant stage of a large development, whereby the assessment can inform developers of potential constraints and take these into consideration through the design phase. A variety of noise sources can be inputted into the noise map, from transport (Figure 1) to single source output (Figure 2) which can significantly effect the propagation of the noise. Cadna also has a 3D function (Figure 3), which can be particularly useful in high rise blocks or buildings with large facades, where noise levels can vary significantly.

Why do developers need a BS8233 Noise Assessment?

When developing a residential property, school, healthcare facilities or hotels (or any other premises that could be defined as noise sensitive), if the development site is near to  transport noise such as a road or railway then it is likely that the Local Authority will request a BS8233 noise survey to be undertaken to ensure that appropriate internal and external noise levels can be achieved to guarantee the amenity of the future occupants. BS8233 sets the following noise criteria:

How is a BS8233 noise survey conducted? 

The aim of a noise survey is to gain a baseline measurement of the noise environment within the vicinity of your proposed development. Once the noise environment has been defined, the potential noise impact on residential dwellings can be assessed. The level of noise impact is analysed according to BS8233:2014 to ensure the future occupants will not be adversely affected by noise.

  • We will carry out an noise measurements to establish the noise levels across the development site. Measurements can include for road, rail and aircraft noise and could be attended or unattended depending on the source;
  • We calculate the predicted noise levels at the façade of the development as well as within the external amenity areas due to the existing sources;
  • We recommend appropriate mitigation measures to protect the external areas;
  • We will calculate the internal noise levels to allow the provision of appropriate glazing and ventilation specifications as required; and
  • We will provide a technical report which is submission to your local authority to support the planning application.

What will be in the Noise Impact Assessment report? 

The purpose of the technical report is to outline to the Local Authority how ‘Good Acoustic Design’ has been implemented in the design of the development to ensure appropriate control measures are being installed. The noise survey report will outline the following:

  • Detail of the proposed development and the existing area including any noise sources surrounding the site;
  • The surveying method that has been used to assess the noise incident on site, including monitoring locations, monitoring dates and times, the equipment used, calibration details, and weather conditions ;
  • A summary of the results including the LAeq and LAMax, fast in accordance with the BS8233:204 requirements.
  • An assessment of the noise level results in accordance with BS8233:2014
  • Mitigation measures required to protect the amenity of the future occupants including calculations of the expected noise reduction from the sound insulation scheme.

What Mitigations measures can be expected from your noise report?

The report will aim to apply all reasonable noise control measures to ensure the internal and external noise requirements of BS8233:2014 can be achieved. It is always preferable for noise to be controlled at source, however this is not always feasible. The following mitigations measures can be applied:

  • Natural corridors and distancing from the existing sources;
  • The orientation and internal layout of the proposed Buildings;
  • Acoustic Barriers and Bunds;
  • Acoustic Glazing; and.
  • Alternative Ventilation Schemes.

Why do NIAs matter?

Noise can have an effect on health, wellbeing, productivity and the natural environment. Noise is considered to be any unwanted or disturbing sound that affects the health and well-being of humans and other organisms. Noise pollution impacts millions of people on a daily basis. Exposure to loud noise can also cause high blood pressure, heart disease, sleep disturbances, and stress. These health problems can affect all age groups, especially children. Many children who live near noisy airports or streets have been found to suffer from stress and other related issues, such as impairments in memory, attention level, and reading skills.

Cities have become the epicentre of this type of pollution, which, is severely damaging to humans . So much so that the European Environment Agency estimates that noise is responsible for 72,000 hospital admissions and 16,600 premature deaths every year in Europe alone. (Noise — European Environment Agency (europa.eu). In the UK alone, cities take up 8% of the land whilst accounting for 54% of the population. As cities expand larger and urban populations grow, the problem of noise pollution will only get worse, and thus the focus upon mitigating all forms of noise pollution will become ever more prevalent and important.

How can Omnia help?

Omnia has extensive experience of producing NIAs for a number of clients, with varying sized developments. We’d be happy to assist you in any upcoming projects or enquiries you may have, and look forward to working with you.

If you’d like Omnia’s help with your project, contact us to speak to one of our team.

Winter Groundwater Monitoring

Winter Groundwater Monitoring

Winter Groundwater Monitoring

Olivia Maxwell: 8 November 2021

What is continuous Winter Groundwater Monitoring?

Winter groundwater monitoring utilising dataloggers allows continuous recording of groundwater levels throughout the winter period, usually from October to March.  Groundwater depths are recorded in order to capture the shallowest groundwater depths for the site. Groundwater depth is typically recorded every 1 hour for 24 hours every day. This allows all groundwater level fluctuations to be captured and provides the most robust data set when compared to spot monitoring.

Why is continuous monitoring useful?

Continuous Winter Monitoring is useful to support planning applications. It is often required as a condition of the development to enable the shallowest groundwater level to be captured, and an assessment of the whole winter groundwater level is required.

The shallowest annual groundwater level is required to assist the drainage design, to enable the ‘worst case’ conditions to be quantified and allowed for in the design process.

In addition, continuous monitoring can provide vital information on groundwater levels to aid foundation design.

What are the benefits of Continuous Winter Groundwater Monitoring?

The benefits of continuous winter groundwater monitoring are extensive. The data is highly accurate (recording to ± 0.3cm) and provides a robust and detailed data set by recording the groundwater levels every hour. This means all fluctuations are captured that spot monitoring could miss, providing a more robust dataset.

The groundwater level data can be easily compared to rainfall data to observe patterns and recharge rates following periods of heavy rainfall, or the data can show that groundwater on a site is influenced by another factor if a correlation between rainfall isn’t seen.

Continuous winter groundwater monitoring can provide cost savings by capturing the ‘worst-case’ conditions early in a project lifespan, avoiding the need for aspects to be redesigned or found not to be suitable.

If you’d like Omnia’s help with your project, contact us to speak to one of our team.

The Importance of Site Investigation for Foundation Design

The Importance of Site Investigation for Foundation Design

The Importance of Site Investigation for Foundation Design

Rhys Bradley: 21 October 2021

Why do we carry out site investigations?

Site investigation is a fundamental aspect in foundation design, to assess the heterogeneous nature of the ground and to prevent potential failure of the foundation through comprehensive geotechnical evaluation of ground conditions beneath a potential development. Omnia has a team of highly qualified individuals and we use a multi-disciplinary approach to our work to assess ground conditions via the in-situ and laboratory testing methods to aid in foundation design.

It is important to understand ground conditions while conducting a geotechnical site investigation, to conform to regulations set out by the NHBC, CIRIA and alike so that safety and the structural integrity of development can be observed.

What methods are used during a site investigation?

Site investigations aid foundation design by collecting a diverse array of data sets both in-situ; such as TRL probing and Hand Shear Vanes, as well as, the collection of soil samples to be submitted to geotechnical laboratory specialists under UKAS accreditation. The collection of samples and data points are aided through the use of various intrusive ground methods, which can assess the ground conditions in both  the near-surface and deep sub-surface through techniques such as hand pitting, windowless sampling, cable percussive drilling and rotary coring. Geotechnical site investigations are tailor-designed to the client’s specifications and architectural concepts to assess the suitability of plans, as well as aiding in the structural design of future construction. Omnia can also provide a geotechnical assessment of current structures to assess ground conditions of buildings suffering from issues like differential settlement.

Geotechnical site investigations are an indispensable process for assessing the ground conditions to aid in foundation design, as the data obtained by our qualified engineers support further processes in the construction of a building to ensure its structural viability and maintain its suitability for future occupancies.

Should you require site investigations to aid in geotechnical design please contact us.

Why Do We Conduct Phase 1 Desk Top Studies?

Why Do We Conduct Phase 1 Desk Top Studies?

Why Do We Conduct Phase 1 Desk Top Studies?

Craig Tyrrell: 4 October 2021

What is a Phase 1 DTS?

A Phase 1 Desk Top Study (or Desk Study) is a review of all available published information relating to a site’s historical, environmental, and geological setting. The purpose of this review is to determine an initial risk rating to plan the following stages of investigation. This is done by identifying any potential ground or environmental related hazards that can pose a potential risk to human health and controlled waters.

Carrying out these studies often saves time and money by identifying potential contamination risks at an early stage, which helps to quickly establish how to proceed with any site investigation, or whether a site investigation is not required.

When is a Phase 1 Desk Top Study needed?

A Phase 1 Desk Top Study should be undertaken at the start of the process of site assessment and  should provide a summary of the site settings through a site walkover and data review. This leads through to the production of a Conceptual Site Model (CSM), where if potentially active pollution pathways are identified will shape any subsequent Phase 2 intrusive ground  investigation.

Phase 1 Desk Top Studies are generally required by the Local Planning Authority as part of the regulatory requirements of planning departments, National Home Building Council (NHBC) and the Environment Agency.

What’s included in a Phase 1 Desk Top Study?

Phase 1 Desk Studies generally consist of the following:

  • Review of site settings including:

Current and Historical Industrial Land Use that are pertinent to the site development. This should identify any potential sources of contamination that can have a potential risk to future site users and involves review of historical mapping dating back to the late 1800’s and a physical site walkover.

Desk based assessment of Waste Sites and Landfill records– this includes any pollution incidents, waste exemption etc.

 

  • Hydrogeology – This includes the presence of Aquifers in both superficial and bedrock deposits as well as groundwater vulnerability and, surface and groundwater abstractions.
  • River and Coastal Flooding – Includes the Risk of Flooding from Rivers and Sea (RoFRaS), Historical events and flood zones.
  • Geology – includes Made Ground, Superficial and bedrock Geology.
  • Natural Ground Subsidence – Shrink swell clays, Running Sands, Compressible and Collapsible Deposits, and Landslides.
  • Mining, ground workings and natural cavities – Mining is much more of a risk in the northern counties and thus contact with the Coal Authority may be needed.

Benefits of a Phase 1 Desk Study

  • Phase 1 DTS provides an insight into possible environmental and geotechnical concerns that may have been identified by the preliminary conceptual site model.
  • It means that any risks identified can be specifically targeted during an intrusive investigation and to assess the implications any potential aspects may have on land liabilities and value as part of a property transaction.
  • In some cases, it is possible to remove the need for an intrusive investigation if there is an absence of any potential risks however this is ultimately decided by the Local Planning Authority.

What about after a Phase 1 Desk Study?

In most cases, if a Phase 1 Desk Top Study has been requested by a Planning Condition this is because the regulator hold information on the general area such that it is often the case that a Phase 2 site investigation will be required. The Phase 2 investigation follows a Phase 1 Desk Top Study in order to consider potential risks to future site users that have been identified in the CSM in relation to  source, pathways, and receptors. These site investigations can also be requested for geotechnical assessment to aid in proposed design works and it is cost effective to combine both geotechnical and environmental aspects.

If you’d like Omnia’s help with your project, contact us to speak to one of our team.

The Wonder of Geology!

The Wonder of Geology!

The Wonder of Geology!

Archie Bunney: 7 July 2021

Geology is the study of the rocks and minerals beneath our feet and, if you are lucky enough to live somewhere with even a hint of topography (so not Portsmouth!), visible in the natural landscape of river valleys, mountains, cliffs, and hillsides. My first memories of being intrigued and captivated by geology were from visiting the Lake District from before I could walk, let alone knew what “glacial, U-shaped valleys carved out of 450 million year old ricks” meant!

Even to experienced geologists, the time scales over which geological processes operate can still be daunting and make all of human history seem insignificant. Geologists use the rocks themselves to interpret Earth’s history using a principle called “Uniformitarianism”. The present is the key to the past, where modern Caribbean limestone forming in tropical seas at shallow depths indicates that limestones from hundreds of millions of years ago also formed in tropical seas at shallow depths.

Part of the wonder of geology is how much a seemingly boring rock face can reveal. Deformation intense enough to build mountains or destroy continents; desert sandstorms, flooding, and earthquakes from hundreds of millions of years ago; the lifestyles of ancestral plants and animals; and even massive gaps in time (“unconformities”) where no rock was deposited at all. The rocks immediately either side of an unconformity can be completely different colours, with completely different compositions, and can be tilted and deformed into completely different orientations.

Geology has a special place in my heart because of how influential it has been on human evolution and development. This extends as far back as the rocks used to build ancient monuments like the Pyramids of Giza and Stonehenge; through the selection of hilltops on which Iron Age civilisations built their forts, the historic development of “mining towns”, and the construction of the UK canal network; to variable vulnerability to/protection from the impacts of anthropogenic climate change.

That being said, the most breath-taking and perhaps the most easily appreciated aspect of geology is the creation of unparalleled natural beauty all around the world, with a significant amount of variation within the comparatively small British Isles. From the mountains of the Highlands to the white cliffs of Dover, and from ancient lava flows on the Giant’s Causeway to glaciated hillsides of the Brecon Beacons.

Geology is all around us, the only trick is knowing where to look!