About Us

JACA & SIERRA TESTING LABORATORIES is a soil and material testing laboratory and geotechnical engineering firm based on the island of Puerto Rico

Quality Systems

Jaca & Sierra Testing Laboratories was established in 1967 by Engineers Carlos R. Sierra Silva and Luis Jaca Méndez. Nowadays it is one of largest geotechnical services firm in the Caribbean covering the island of Puerto Rico, U.S. Virgin Islands, British Virgin Islands, Lesser Antilles and other locations within the Caribbean. J&S services reliability is based on experience, training and internal quality systems.

Jaca & Sierra in Trujillo Alto, PR is accredited by the AASHTO Accreditations Program (AAP) for soil, construction materials and aggregates testing. In order to fulfill with the regulations imposed by the AASHTO Materials Reference Laboratories (AMRL) and the Concrete and Cement Reference Laboratories (CCRL), we are enrolled in their proficiency sample testing program. Also, JSTL has been validated by the U.S. Army Corps of Engineers for the same standards as for AAP.


To surpass our clients’ expectations in reliability, quality and timeliness of our consulting and testing work preserving our most treasured values of good service, practical reasoning and technical sagacity that has characterized Jaca & Sierra Testing Laboratories since its establishment 45 years ago.


To maintain an efficient professional services entity comprised of customer service oriented, well trained and experienced team of geo-professionals and technical personnel provided with state of the art testing equipment and tools to complete the contracted tasks.


ASTM D3740: Standard Practice for Minimum Requirements for Agencies Engaged in the Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction

ASTM E329: Standard Specification for Agencies Engaged in the Testing and/or Inspection of Materials Used in Construction

AASHTO R18: Quality System

ASTM 1077: Concrete and Cement Reference Laboratories (CCRL) Quality Systems

Our Team