Abstract
This research focuses on the hydrogeological characterization of the aquifer system in the Isla Chica and La Trocha communities. This system corresponds to a transboundary aquifer within the San Juan River basin (Costa Rica-Nicaragua). It is important to note that the groundwater is used by the local residents and migrants who live itinerantly in these areas. In addition, there are very few studies of this nature conducted in the region. This work identifies the presence of two aquifers: the first is a shallow, unconfined aquifer covered by a clay layer, with low transmissivity, consisting of intercalated layers of sand and clay that are captured through hand-dug wells. The second is a deeper, semi-confined aquifer, with an average thickness of 40 m, composed of volcaniclastic sands. This aquifer is exploited through drilled wells. The static level recorded for the drilled wells may reflect an equilibrium level between aquifers, typically ranging from 10 to 30 m deep. The deeper aquifer is overlain by a poorly permeable reddish clay layer with an average thickness of 30 m. The groundwater flow direction is from South to North, toward the San Juan River. Hydrogeochemically, the mixed water is classified as calcium bicarbonate. According to the GOD model, the vulnerability of the shallow aquifer to contamination is low to medium. The potential recharge, calculated using the method proposed by Schosinsky (2006), is estimated to be between 357.82 mm and 491.70 mm per year.
References
Adimalla, N., y Venkatayogi, S. (2018). Geochemical characterization and evaluation of groundwater suitability for domestic and agricultural utility in semi-arid region of Basara, Telangana State, South India. Applied Water Science, 8(1), 44. https://doi.org/10.1007/s13201-018-0682-1
American Public Health Association (APHA). (2017). Standard methods for the examination of water and wastewater (23th ed.). American Public Health Association.
Barrantes, O., y Sandoval, L. (2016). Uso/cobertura de la tierra en los cantones de Upala, Guatuso y Los Chiles en el año 2011. Revista Geográfica de América Central, 56, 59–91. https://doi.org/10.15359/rgac.1-56.3
Procaduría General de la República. (01 de setiembre de 2015). Reglamento para la calidad del agua potable No 38924-S. https://www.pgrweb.go.cr/scij/Busqueda/Normativa/Normas/nrm_texto_completo.aspx?param1=NRTC&nValor1=1&nValor2=80047&nValor3=101480&strTipM=TC
Denyer, P., y Alvarado, G. (2007). Mapa geológico de Costa Rica. [Escala 1:40 0000]. Librería Francesa.
Foster, S., Hirata, R., Gomes, D., D’Elia, M., y Paris, M. (2002). Groundwater Quality Protection – a guide for water utilities, municipal authorities, and environment agencies. The World Bank.
Fuentes-Schweizer, P., Morales-Mora, E., Vargas-Muñoz, R., Barrantes-Jiménez, K., y Chacón- Jiménez, L. (2023). Physical, chemical, and microbiological characteristics of groundwater in Los Chiles, Costa Rica, and its association with land use. UNED Research Journal, 15(2), e4656. https://doi.org/10.22458/urj.v15i2.4656
Instituto Nacional de Estadística y Censos (INEC). (2021). Anuario Estadístico 2019-2020. https://admin.inec.cr/sites/default/files/2022-11/reanuario2019-2020_0_2.pdf
Instituto Nacional de Estadística y Censos (INEC). (2010). Anuario Estadístico 2010. https://inec.cr/wwwisis/documentos/INEC/Anuario_Estadistico/Anuario_Estadistico_2010.pdf
Liu, F., Zou, J., Liu, J., Zhang, J., y Zhen, P. (2022). Factors controlling groundwater chemical evolution with the impact of reduced exploitation. Catena, 214, 0341-8162. https://doi.org/10.1016/j.catena.2022.106261
Malavassi, E., y Madrigal, R. (1970). Estudio geológico regional de la zona Atlántico norte de Costa Rica. Informe Técnico y notas geológicas, 9(32), 1-12.
Mukonazwothe, M., Munyai, L. F., y Mutoti, M. I. (2022). Groundwater quality evaluation for domestic and irrigation purposes for the Nwanedi Agricultural Community, Limpopo Province, South Africa. Heliyon, 8(4), e09203. https://doi.org/10.1016/j.heliyon.2022.e09203
Organización Meteorológica Mundial (OMM). (1972). Manual de instrucciones, estudios hidrológicos. OMM. https://library.wmo.int/viewer/32688/download?file=wmo-z_1972_man.pdf&type=pdf&navigator=1
Programa Organización de las Naciones Unidas para la Educación, la Ciencia y la Cultura (Unesco). (2015). Estrategia regional para la evaluación y gestión de los Sistemas Acuíferos Transfronterizos en las Américas. https://unesdoc.unesco.org/ark:/48223/pf0000235394
Ramírez, R. (2013). Incorporación de la zona no saturada en la metodología de vulnerabilidad higrogeológica del método GOD. Senara.
Schosinsky, G. (2006). Cálculo de la recarga potencial de acuíferos mediante un balance hídrico de suelos. Revista Geológica de América Central, 34–35, 13–30. https://doi.org/10.15517/rgac.v0i34-35.4223
Schosinsky, G., y Losilla, M. (2000). Modelo analítico para determinar la infiltración con base en la lluvia mensual. Revista Geológica de América Central, 23, 43–55. https://doi.org/10.15517/rgac.v0i23.8579
Soto, D., y Alvarado, G. (2012). Peperitas en Costa Rica. Revista Geológica de América Central, 47, 55–68. https://doi.org/10.15517/rgac.v0i47.6486
Vargas, R. (2022). Caracterización hidrogeológica de las comunidades Isla Chica y La Trocha, cantón de Los Chiles, Alajuela. [Tesis de licenciatura]. Universidad de Costa Rica. https://repositorio.sibdi.ucr.ac.cr/items/01d191dd-d6c8-45c2-8bf8-1c5aab0bbd71/full
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