Advanced DQRA – Dealing with Non-Standard Risk Assessments

Date: Thursday 3rd July 2025
Venue: Priory Rooms and Conference Centre, 40 Bull Street, Birmingham, B4 6AF

Tickets are £185 for members, £250 for non-members (includes SOBRA membership). 
We offer a 50% discount for local authority or not-for-profit employee members. 
Please nominate your preferred workshop AFTER you have reserved your place.

BOOKINGS CLOSE 11PM ON 26 JUNE

Programme

09.00

Registration, Tea & Coffee & Early Networking


09.45

Introduction, Morning Chair

Kate Baker (SoBRA Chair)


MORNING SESSION 1- Thoughts on DQRA

09.55

Unconscious Bias in Risk Assessment

Richard Brinkworth (RSK)


10.15

Building Confidence in Non-Standard Risk Assessments: Advice from a Regulatory Perspective

Ian Martin (EA)

More info

Assessing environmental risks from chemicals and other hazards can be a challenge to everyone – the regulator included!  This presentation will provide reflections on a wide range of potential scenarios for environmental risk from emerging pollutants to novel exposure scenarios, and provide advice on many aspects of the design, application, and presentation/communication of its findings that illustrate how confidence and consensus can be built from a set of broadly defined principles.  The presentation will be given by Ian Martin from the Chief Scientist’s Group at the Environment Agency, who has spent many years looking at chemical risks to health and the wider environment under a wide range of non-standard scenarios.


10.35

Advanced Human Health DQRA for Part 2A Environmental Protection Act (1990) as amended – A Case Study

Paul Nathanail (LQM)

Judith Nathanail (LQM)

More info

The narrative definitions of Category 1 and 2 are the launch pad for a quantitative risk assessment under Part 2A. No generic assessment criteria exist to define the upper boundary of category 3. Site specific assessment criteria need to reflect both site specific conditions affecting exposure and doses associated with significant harm for a local authority to reasonably decide that land falls into category 1 or 2. Advanced sampling and analytical techniques are usually needed as are risk evaluation tools beyond what CLEA can offer.


10.55

Q & A


11.05

Tea & coffee break


MORNING SESSION 2 – The State of DQRA – Industry Perspectives

11.25

The State of DQRA – A Consultant’s Perspective

Barry Mitcheson (WSP)


11.45

The State of DQRA – A Regulator’s Perspective

Sarah Harris (NRW)


12.05

The State of DQRA – A Client’s Perspective

tbc


12.25

Q & A


MORNING SESSION 3 – Introduction to Workshops

12.35

Workshop 1 – Approaches to deal with different building types

Amy Juden (EPG)

More info

All models are wrong – but this workshop will explain when some are useful.  They can be used to probe understanding of the risk at a site.  Any model for vapour intrusion or ground gas risk should consider the specific ground to indoor air pathways that will be present on a site.  This requires a good understanding of different types of floor, foundation, and basement construction and where soil gas migration will occur through them.  Migration of soil gas into basements via groundwater also needs to be considered.  The generic CLEA model for vapour intrusion is not suitable for most UK developments.  This is because of the assumptions that the J&E model it is based on makes, with respect to soil gas flow into the building, not least that there is a basement included as standard.  The Characteristic Situation system used to define ground gas risk is not based on any consideration of building construction or quantified risk assessment.  It is a purely empirical system and if a DQRA is required, gas flow into the building must be assessed.

The workshop will explore different types of building construction in the UK and how to incorporate these into models for vapour intrusion or ground gas risk assessment.  Gas migration models can then be used to assess the effectiveness of different mitigation measures, model the requirements for protection redundancy and provide confidence that the mitigation design will meet risk-based requirements.

Facilitators: Steve Wilson and John Andrews (EPG)


12.45

Workshop 2 – Approaches to deal with contaminant mixtures

Stephanie Cox (E3P)

More info

Using a live case study, we will walk through a situation where phthalates — typically considered immobile due to their low solubility and strong adsorption to organic matter — became mobilised in the presence of BTEX (Benzene, Toluene, Ethylbenzene, Xylene).  This unexpected behaviour rendered traditional Remedial Target Methodology (RTM) models unworkable.  The workshop will step through each stage of the risk assessment process: defining the problem, setting objectives, building the conceptual model, testing generic assumptions, and adapting models to reflect real-world conditions.  Attendees will leave with practical insights into data needs, parameter selection, and how to apply sense checks to ensure solutions are robust and realistic.

Facilitator: – Rachel Dewhurst (Stantec)


12.55

Workshop 3 – Approaches to deal with risks to different sorts of receptors

Becky Whiteley (WSP)

More info

Imagine your client has a site which is a former firing range but is now open acid heathland.  The site is securely fenced, but forms part of a larger Site of Special Scientific Interest (SSSI).  The client is looking for ways to manage the site to maintain the heathland and has come to you for advice on whether the site would be suitable for livestock grazing.  Limited soil sampling has previously been undertaken at the site and this identified contamination of the shallow soils at the site with heavy metals (lead, copper and nickel).  How would you go about assessing the suitability for the site for livestock?  What site investigation techniques could be undertaken?  How could the risks be assessed?  During this workshop we will discuss how we might develop a conceptual model for various livestock grazing scenarios, consider the approaches we might use for assessing the risks to livestock and to the wider food chain, and the data we might require to support such as assessment, as well as considering ways to sense check our approach. 

Facilitator: Barry Mitchinson (WSP)


01.05

Workshop 4 -Approaches to dealing with non standard sources and CSM

Hazel Comyn (Ramboll)

More info

QRA is critical to support End of Waste decisions, helping define when a material ceases to be classified as waste, bringing it to the point at which it is recovered and used as a product, helping drive the Circular Economy.  This workshop will look at how to characterise a potential future source (i.e. the ‘waste’) and develop comprehensive CSMs to cover multiple scenarios based on the variety of settings in which the material may be used (i.e. CSM for a potential site as yet undefined). 

Facilitator: Elizabeth Waterfall (Stantec)


13.15

Lunch & networking


AFTERNOON WORKSHOPS (Parallel sessions)

14.05

Workshops


Tea & coffee break – within workshop period


16.20

Closing Remarks

Workshop leads and Kate Baker (SoBRA Chair)


16.40

Close