both interpretations. Bedford turns on the requirement for the harm to be assessed as ‘serious’ (with significance needing to be very much, if not all, ‘drained away’) in order that it be deemed substantial. Alternatively, paragraph 018 indicates that an important consideration would be whether the adverse impact ‘seriously’ affects a key element of special interest. In both interpretations, it is the serious degree of harm to the asset’s significance which is the key test. Moreover, in accordance with the logic of the Bedford argument, paragraph 018 explicitly acknowledges that substantial harm is a ‘high test’. (emphasis added) 34. Mr Drabble submitted that the issue has been bedevilled by the application of the language to be found in the judgment of Jay J in Bedford Borough Council v Secretary of State for Communities and Local Government [2013] EWHC 2847 (Admin) at [24] which apparently requires the impact on significance to be such that “very much if not all, the significance [is] drained away for harm to be regarded as substantial.” He submits that there is no justification for this gloss and there is accordingly an obvious danger that if one regards the requirement of substantial harm as being synonymous with much if not all of the significance of the asset being drained away then too high a test is being imposed. It is, he submitted, apparent from the Inspector’s Report that this is what has happened in this case. 35. In my assessment, however it is apparent from IR15.12 that, having set out the parties’ views, the Inspector came to his own interpretation of the relevant test for substantial harm which he expressed as “the serious degree of harm to the asset’s significance.” Mr Drabble accepted he could not object to this formulation of the test which reflects the wording of the Planning Practice Guidance and is an expression of Government policy. Similarly, he accepted that no issue could be taken with the Inspector equating ‘substantial’ with ‘serious’. 36. The Inspector continued his analysis of the task before him at IR 15.13. He went on to describe, in practical terms, the identification of the measure of harm to the designated heritage assets individually and cumulatively and the apportionment of appropriate weight to the harm: 15.13 It is a high test indeed and I address these matters in detail below, calibrating the degree of harm identified to each DHA and the weight to be apportioned accordingly. The sum of such harms is then duly considered against any public benefits in the heritage balance anticipated in paragraphs 195 or 196 of the NPPF and, where appropriate, development plan policy.” (emphasis added) 37. It was common ground that no issue can be taken with the Inspector’s statement that the test is a ‘high test’. 12