Theories of flow to a well in a double‐porosity groundwater reservoir are modified to incorporate effects of a thin layer of low‐permeability material or fracture skin that may be present at fracture‐block interfaces as a result of mineral deposition or alteration. The commonly used theory for flow in double‐ porosity formations that is based upon the assumption of pseudo–steady state block‐to‐fissure flow is shown to be a special case of the theory presented in this paper. The latter is based on the assumption of transient block‐to‐fissure flow with fracture skin. Under conditions where fracture skin has a hydraulic conductivity that is less than that of the matrix rock, it may be assumed to impede the interchange of fluid between the fissures and blocks. Resistance to flow at fracture‐block interfaces tends to reduce spatial variation of hydraulic head gradients within the blocks. This provides theoretical justification for neglecting the divergence of flow in the blocks as required by the pseudo–steady state flow model. Coupled boundary value problems for flow to a well discharging at a constant rate were solved in the Laplace domain. Both slab‐shaped and sphere‐shaped blocks were considered, as were effects of well bore storage and well bore skin. Results obtained by numerical inversion were used to construct dimensionless‐type curves that were applied to well test data, for a pumped well and for an observation well, from the fractured volcanic rock terrane of the Nevada Test Site.

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The Hantush theory of leaky aquifers with storge in the semiconfining layers is combined with large‐diameter well theory to produce equations that can be used in the analysis of pumped‐well and observation well data for stratified formations. Included in the equations are storage in the pumped well and a linear resistance to flow at the sand face or well bore skin. Three cases proposed by Hantush are considered. These depend upon whether the upper boundary of the overlying semiconfining layer or the lower boundary of the underlying semiconfining layer are constant head or no‐flow boundaries. Laplace transform solutions, valid for the complete time domain, are given for each of the three cases for the hydraulic head in the pumped well, the aquifer, and each of the semiconfining layers. Type cures obtained by numerical inversion are selected to illustrate the effects of well bore storage, well bore skin, and leakage. Although several dimensionless parameters are involved, these parameters tend to influence the character of different portions of the type curves, suggesting that unique matches are possible. The type curves show that well bore storage in a large‐diameter well may completely obliterate effects of leakage derived from compressible storage in semiconfining layers. For the purposes of aquifer testing, it may be possible to reduce the magnitude of well bore storage in a large‐diameter well and thus reveal the presence of leaky semiconfining layers. This may help to prevent erroneous interpretation of the well test data and incorrect evaluation of the aquifer parameters.

A Laplace transform solution was obtained for the injection of a tracer in a well situated in a homogeneous aquifer where steady, horizontal, radially convergent flow has been established due to pumping at a second well. The standard advection‐dispersion equation for mass transfer was used as the controlling equation. For boundary conditions, mass balances that account for mixing of the tracer with the fluid residing in the injection and pumped wells were used. The derived solution, which can be adapted for either resident or flux‐averaged concentration, is of practical use only for the pumped well. This problem is of interest because it is easily applied to field determination of aquifer dispersivity and effective porosity. Breakthrough curves were obtained by numerical inversion of the Laplace transform solution. It was found that tracer mixing with fluid in the pumped and injection wells, especially in low‐porosity aquifers, may have a significant influence on the shape of the tracer breakthrough curves.

Flow and head variations in stationary linear stream‐aquifer systems are obtained through application of the convolution equation. Four highly idealized cases involving finite and semi‐infinite aquifers, with and without semipervious stream banks, are considered. Equations for the instantaneous unit impulse response function, the unit step response function, and the derivative of the unit step response function are given for each case. Head fluctuations in the aquifer due to an arbitrarily varying flood pulse are obtained for the cases involving a finite aquifer with and without a semipervious stream bank. Flow in and out of the aquifer at the stream bank is determined for the same cases and demonstrates the value of the convolution equation in evaluating the base flow. Head variations, and to a lesser extent flow variations, are apparently relatively insensitive to variations in aquifer diffusivity.