ASTM D4520-03

The injectivity of a water is best determined by measurements as near to the well as possible to minimize changes in water properties due to air contact and time. This practice describes how core flow tests are carried out near the well.

This practice permits the differentiation of permeability losses from the effects of chemical interaction of water and rock and from the effects of plugging by suspended solids. The procedure can be utilized to estimate the chemical and filtration requirements for the full-scale injection project.

Application of the test results to injection wells requires consideration of test core selection and geometry effects.

This practice as described assumes that the water does not contain free oil or other immiscible hydrocarbons. The presence of free oil would require the method to be modified to account for the effect of oil saturation in the test cores on the water permeability.

1.1 This practice covers a procedure for conducting on-site core flood tests to determine the filtration and chemical treatment requirements for subsurface injection of water.^,

1.2 This practice applies to water disposal, secondary recovery, and enhanced oil recovery projects and is applicable to injection waters with all ranges of total dissolved solids contents.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.