Underground mine designs typically try to avoid extraction beneath streams and rivers of any significant size, especially when the overburden rock thickness between the stream bed and the mine is thin. Potential issues with mining beneath streams include excessive groundwater inflow to the mine, weak ground (roof, floor, and pillar) conditions, horizontal stress effects, as well as stream loss and other potential adverse environmental effects. However, there are times when crossing beneath a stream or river is necessary to move into a new area of mineral reserve without creating additional mine access points from the ground surface. Often, stream crossings are completed without thorough assessment, potentially resulting in increased costs, decreased safety, and, in some cases, failure to advance the mine. Selection of the most favorable location(s) to cross the stream must account for numerous factors and the associated assessment often requires a multi-disciplinary approach. Stream crossing investigations often require geological, hydrogeological, geotechnical, and geophysical expertise. Phases of stream crossing investigations include desktop evaluation of maps and aerial photography, stream bed observations, drilling, detailed rock core logging, downhole geophysical surveying, hydraulic conductivity testing (packer testing), geotechnical laboratory testing, assessment, and reporting. The deliverables from a stream crossing assessment typically include geological, geotechnical, and hydrogeological characterization of potential stream crossing locations, classification of favorable and unfavorable crossing locations, recommendations for entry design and pillar sizing, and recommendations for if, and how, to conduct pre-grouting activities. Examples of technical aspects of data collection and assessment are provided based on decades of industry experience conducting stream crossing assessments in various underground mining scenarios.

地下矿山的设计通常试图避免在任何大大小的溪流和河流下开采，特别是在河床和矿山之间的覆岩厚度很薄的情况下。溪流下开采的潜在问题包括过多的地下水流入矿井，弱地面（屋顶，地面和支柱）状况，水平应力影响以及溪流损失和其他潜在的不利环境影响。但是，有时需要穿越溪流或河流下方才能进入新的矿藏区域，而又不从地面创建额外的地雷入口。通常，未经充分评估就完成了跨河穿越，有可能导致成本增加，安全性下降以及在某些情况下无法推进采矿。选择最适合穿越河流的地点必须考虑许多因素，而相关的评估通常需要采用多学科方法。跨河调查通常需要地质，水文地质，岩土工程和地球物理方面的专业知识。河道穿越调查的阶段包括桌面评估地图和航拍，河床观测，钻探，详细的岩心测井，井下地球物理勘测，水力传导率测试（封隔器测试），岩土实验室测试，评估和报告。跨河评估的可交付成果通常包括潜在跨河位置的地质，岩土和水文地质特征，有利和不利穿越位置的分类，有关入口设计和支柱尺寸的建议，以及有关是否以及如何进行预灌浆活动的建议。根据数十年来在各种地下采矿方案中进行跨河评估的行业经验，提供了数据收集和评估的技术方面的示例。