Preserving Peru's Heritage: wall painting stabilization and monitoring as part of the Getty’s Seismic Retrofitting Project

The Seismic Retrofitting Project (SRP), launched in 2009, represents a pioneering collaboration between the Getty Conservation Institute (GCI) and the Ministerio de Cultura del Perú, with the participation of key academic and cultural institutions and Kuñotambo´s community. This project aimed to blend traditional building methods, local materials, and cutting-edge technologies to improve the seismic resilience of historic earthen structures without compromising their historical value. The initiative focused on enhancing the seismic performance of these buildings while ensuring the in-situ preservation of their wall paintings. A standout achievement of the SRP was the comprehensive seismic retrofitting completed at the 17th-century Church of Kuñotambo in 2019. This site was particularly challenging due to its thick adobe walls, a truss roof, and unstable earthen-based wall paintings which were preserved and conserved in-situ, deviating from the common practice of strappo and stacco detachment. The project successfully implemented earth-based injection grouts tailored for the conservation of Kuñotambo’s wall paintings, utilizing local materials like 'gigantón', a local cactus (Trichocereus pachanoi), and adapting standard tests for lime-based grouts to suit the specific needs of earthen-based wall paintings. This innovative approach not only stabilized the wall paintings during the seismic retrofitting but also set a precedent for the preservation of similar wall paintings in seismic zones. A vital component of the SRP was the development and implementation of a monitoring strategy involving all stakeholders, from the local community to international conservators. This strategy employed a three-tiered approach: monthly monitoring by the community, annual assessments by the Arzobispado del Cusco as the owner of the church, and comprehensive evaluations every five years by a team of international and local wall painting conservators including the Dirección Desconcentrada del Cusco, the Arzobispado del Cusco and the Getty Conservation Institute., facilitating the capacity building. This approach aimed to empower the local community in the conservation of their cultural heritage, facilitate the evaluation of materials and treatments over time through a detailed documentation process including forms, graphic, and photographic records. The project's results, encapsulating the development of the earthen-based injection grout and the monitoring strategy, along with before-during-and-after documentation of the intervention, have been disseminated in both English and Spanish, contributing significantly to the field of cultural heritage conservation. This collaborative effort not only achieved its goal of enhancing the seismic resilience of historic earthen architecture but also underscored the importance of community involvement in preserving cultural heritage, offering valuable insights for future conservation projects worldwide.