Exemplary methods and systems of the invention minimize errors in the manufacture or management of aggregate-containing construction materials such as concrete. Aggregates used for making concrete are stored or weighed in dry bulk bin type hoppers, and conveyed from these hoppers into mixer drums which batching or mix the concrete. The hoppers or conveyor belts may contain sensor probes for measuring moisture levels in the aggregate. These sensor probes require calibration from time to time, but time and expense are required for proper calibration, leading to habitually erroneous moisture level data used in the industry on a daily basis. The present inventors believe that the smallest inaccuracies in aggregate moisture level readings can have profound effects on the properties of the resultant concrete product. To confront this long suffered problem, the present inventors surprisingly discovered that the inaccuracy of these aggregate moisture sensors, as used for evaluating the aggregate as a dry bulk material, can be detected and even addressed through the use of slump monitoring systems during delivery to evaluate the concrete slurry mix prepared from the aggregates.