A method for the in situ non-destructive remediation and/or repair of a pipeline comprising the steps of: i. making available a composition comprising: a) at least one resin selected in the group consisting of an acrylic, methacrylic, unsaturated polyester, acrylate polyester, epoxy acrylate, polyurea acrylate, bisphenol acrylic, vinyl, vinyl ester, vinyl ether, polyether acrylate resin, and a combination thereof; b) at least one resin selected in the group consisting of an epoxy, oxirane, oxethane, polyurethane, cycloaliphatic epoxy resin, and a combination thereof; c) at least one photo-initiator compound that can be photoactivated by irradiation with an actinic light source having a wavelength between 100 and 600 nm; ii. adding to the composition of step i): d) at least one co-hardener compound selected in the group consisting of a semilatent co-hardener, a co-hardener at room temperature and a combination thereof, said cross-linking action not depending on the presence and/or persistence of irradiation with a source of actinic light having a wavelength between 100 and 600 nm; iii. impregnating a substrate with the composition of step ii); iv. inserting the impregnated substrate inside the pipeline to be remediated and/or repaired; v. expanding or everting, preferably by means of the inversion technique, said substrate against the internal surfaces of the pipeline by applying a constant pressure flow of air or the like or of liquid; vi. activating the at least one photoinitiator comprised in the composition by irradiation with an actinic light source having a wavelength between 100 and 600 nm; vii. removing the application of the flow of air or the like or liquid under pressure, preferably after a waiting time of between 1 and 60 minutes, more preferably between 10 and 40 minutes. i. making available a composition comprising: a) at least one resin selected in the group consisting of an acrylic, methacrylic, unsaturated polyester, acrylate polyester, epoxy acrylate, polyurea acrylate, bisphenol acrylic, vinyl, vinyl ester, vinyl ether, polyether acrylate resin, and a combination thereof; b) at least one resin selected in the group consisting of an epoxy, oxirane, oxethane, polyurethane, cycloaliphatic epoxy resin, and a combination thereof; c) at least one photo-initiator compound that can be photoactivated by irradiation with an actinic light source having a wavelength between 100 and 600 nm; a) at least one resin selected in the group consisting of an acrylic, methacrylic, unsaturated polyester, acrylate polyester, epoxy acrylate, polyurea acrylate, bisphenol acrylic, vinyl, vinyl ester, vinyl ether, polyether acrylate resin, and a combination thereof; b) at least one resin selected in the group consisting of an epoxy, oxirane, oxethane, polyurethane, cycloaliphatic epoxy resin, and a combination thereof; c) at least one photo-initiator compound that can be photoactivated by irradiation with an actinic light source having a wavelength between 100 and 600 nm; ii. adding to the composition of step i): d) at least one co-hardener compound selected in the group consisting of a semilatent co-hardener, a co-hardener at room temperature and a combination thereof, said cross-linking action not depending on the presence and/or persistence of irradiation with a source of actinic light having a wavelength between 100 and 600 nm; iii. impregnating a substrate with the composition of step ii); iv. inserting the impregnated substrate inside the pipeline to be remediated and/or repaired; v. expanding or everting, preferably by means of the inversion technique, said substrate against the internal surfaces of the pipeline by applying a constant pressure flow of air or the like or of liquid; vi. activating the at least one photoinitiator comprised in the composition by irradiation with an actinic light source having a wavelength between 100 and 600 nm; vii. removing the application of the flow of air or the like or liquid under pressure, preferably after a waiting time of between 1 and 60 minutes, more preferably between 10 and 40 minutes.