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Use of Horizontal Directional Drilling - HDD for large diameter (OD>20 inches) pipeline installation started in the second half of the seventies. Since then the method became the preferred alternative for situations in which it is necessary an underground pipeline but there are concerns about digging trenches. Crossings of roadways, water bodies and environmental sensitive areas are typical examples of its application. Technical and economic feasibility of HDD depends significantly on the properties of the materials that will be drilled. Lack of information about these materials can lead to several problems as: schedule delays, cost elevation, pipeline damage, unforeseen environmental impacts and even the failure of the entire operation. Ground investigation campaigns for HDD should define a consistent geological-geotechnical model, which must include determination of behaviour parameters for soil and rock masses that will be drilled. Thus it is proposed an investigation in tree stages: review of available geological-geotechnical information, site reconnaissance, and field survey. (author)