## 3 Results and Discussion
### Environmental Results
Diesel consumption activities represent 61.63% (1.702 \(\times\) 10\({}^{-6}\) kg Sb eq), while the impact of 20.15% (3.01 \(\times\) 10\({}^{-8}\) kg Sb eq) is visible in reference to the steel consumption process used mainly in the construction of the aggregate production plant itself and its mechanical components. Steelis mainly composed of minerals such as iron, which is considered to be a naturally available raw material. Also, although with a lower impact value, the 6.58% (3.01 \(\times\) 10\({}^{-8}\) kg Sb eq) of using lubricating oil stands out. This impact is justified in this category as synthetic lubricating oils are mainly made up of petroleum derivatives considered as a resource in nature or by the minerals themselves. Finally, and within the EPD methodology, the results of the Eutrophication impact category are analyzed, which is directly related to the excessive enrichment of nutrients in the water due to the emission of nitrogen compounds resulting from the combustion process. It is therefore logical that in this impact category, almost 74.36% 6.14 \(\times\) 10\({}^{-3}\) kg PO\({}_{4}\) eq) of the total impact comes from fuel consumption and flaring activities. The impact of 24.14% (1.99 \(\times\) 10\({}^{-3}\) kg PO\({}_{4}\) eq) from the water recycling activity is also highlighted, since, although there is a water purification process, this process is generally dedicated exclusively to the cleaning of suspended particles from the washing process and does not eliminate those compounds (nitrogen oxides) that can be acquired. The ReCiPe methodology and its assessment in the land use category, which reflects the transformation and use of natural land with a potential for agricultural use for other purposes, is affected by the land use resource, where it accounts for 86.30% (0.021 m\({}^{2}\) crop eq) of the total impact. The remaining 13.70% (0.03 m\({}^{2}\) crop eq) is divided among the other activities. The obtained value of 0.024 m\({}^{2}\) crop eq is a very small effect value, justified by the fact that the magnitude of producing one ton of NCA is negligible. However, if the horizon would be extended to annual production values of NAs from a gravel pit where, for example, the average for Spain is 45.3 Mt [4], the results in this impact category would grow exponentially. Comparing the value of 0.024 m\({}^{2}\) crop eq obtained in this research with the current literature shows a large difference, e.g., the research by [PERSON] et al. calculates it to be 1.05 m\({}^{2}\) crop eq for 1 t of NCA [27]. This major difference is due to the fact that the authors model the activity of producing NCA through the generic SimaPro Gravel, crushed {RoW}, market for gravel process and in this process simulate the use of explosives to produce NCA, severely affecting the land use category. This is demonstrated in this research, where in the sensitivity analysis carried out (see Section 3.3 Sensitivity Analysis) and for scenario 1 (S-1), the use of explosives in the production of NCA implies an 80.91% (0.044 m\({}^{2}\) crop) increase in impact compared to the baseline results in the land use impact category. However, the value is still significantly lower than in the research by [PERSON] et al. [27] and more in line with the result of the research by [PERSON] et al., where they also take into account the use of explosives to produce NAs and obtain a value of 0.065 m\({}^{2}\) arable [1]. Mainly the differences may arise in the use of different environmental assessment methodologies and their weighting/characterization factors for the LCI.