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66 The aggregate specific gravity is generally determined by 3.5 SUMMARY OF AGENCY the contractor or its representative (65% of respondents). Of SPECIFICATION SURVEY the agencies responding, 17% determine the aggregate spe- cific gravity. The dry bulk aggregate specific gravity deter- One of the goals during the implementation of the Super- mined during the design process is used to calculate VMA pave method was the establishment of consistent test meth- during production by 52% of the responding agencies. Seven ods and specifications for HMA across the Untied States. agencies (17%) use the effective specific gravity to calculate Based on the agencies responses, it appears that the first goal VMA during production. Three of these agencies apply a cor- has been relatively successful. The majority of the respond- rection factor to the effective gravity to estimate the bulk spe- ing agencies specify the Superpave consensus aggregate prop- cific gravity. Four agencies (9%) do not calculate VMA dur- erties and source property test methods; however, lower per- ing production. Other agencies publish aggregate specific centages follow the specification values for the consensus gravities to be used for design and production. Only two agen- properties. Agencies provided little indication as to the rea- cies reported measuring the aggregate bulk specific gravity soning behind their changes. Past experience was cited in during production. several instances.