Representative Experience in Studies


        Puerto Rico Aqueduct and Sewer Authority (PRASA)

Over 125,000 persons in Puerto Rico, mostly in rural communities, obtain potable water from over 300 independent systems. Many of these "non-PRASA" systems do not comply with applicable drinking water regulations. As part of a Supplemental Environmental Project (SEP) under the U.S. Clean Water Act, PRASA contracted TCG to perform a fast-track, detailed assessment and inventory update of all known independent systems, for presentation to the U.S. Environmental Protection Agency (EPA) and the Puerto Rico Department of Health (PRDOH). Field teams composed by TCG and ETAG Corporation visited each of the 310 known systems to verify and update record information. Subsequently, a detailed assessment was conducted for each system, in order to (1) determine compliance with present and foreseeable future regulations; (2) determine the viability of integrating each system into PRASA; (3) identify improvements required to allow each system to operate in compliance with local and federal drinking water regulations; and (4) recommend short-term measures that can improve the quality of water produced by each system until it can be brought into permanent compliance. Work was completed in five months. Press on the two links to see more about this study: Non-PRASA1 and Non-PRASA2.

        Puerto Rico Aqueduct and Sewer Authority

Work, conducted during period of 1984 to 1993, comprised the definition of mixing zones and the evaluation of the impacts on receiving waters of the discharges from nine major regional PRASA wastewater treatment facilities (Dorado, Ponce, Guayanilla, Fajardo, Humacao, Mayaguez, Arecibo, Vieques and Barceloneta). as required by Puerto Rico Water Quality Standards Regulations (PRWQSR) in order to obtain an EQB Water Quality Certificate in an NPDES permitting process. Work included intensive effluent sampling, acute and chronic bioassays (using both indigenous and EPA-standard species), hydraulic analyses of outfall diffusers, modeling of achievable dilutions, conceptual designs of modifications to outfall diffusers (when required), and extensive negotiations with environmental regulatory agencies. This assignment provided TCG with an extreme degree of familiarity with the PRASA regional wastewater management.

        Ente Nacional de Obras Hídricas de Saneamiento (ENOHSA), Buenos Aires; Obras Sanitarias, Sociedad del Estado (OSSE), Mar del Plata/Batán, Argentina.

Initial work consisted of an assessment of alternatives for the management of municipal effluents generated by the city of Mar del Plata, Argentina. This city has a stable population of about 500,000, which increases to over 1,000,000 in the summer months, and is the most important beach resort in Argentina. Options for effluent management (additional treatment, ocean outfall, reuse, disinfection alternatives), were analyzed, using a holistic, watershed approach. The problem was complicated by the need to account and provide for a significant industrial component which does not presently receive pretreatment, and by the large seasonal variability in wastewater flow and composition. An assessment of the methods used to manage treatment residuals and bulk discharges to the treatment plant was also performed. The selected approach combined an expansion to the existing preliminary plant with a long ocean outfall. A sample design for a 4.5 KM ocean outfall was prepared, together with a detailed technical specification for turnkey (design-build-operate) construction of the outfall, incorporating water quality-based performance criteria. Subsequently, assistance was provided to OSSE in the procurement and bid evaluation process.

        U.S. Environmental Protection Agency

The U.S. Environmental Protection Agency has selected the Merck, Sharp & Dohme Química plant in Barceloneta, Puerto Rico, as a model case involving the application of both title V regulations and pharmaceutical emission standards. A significant component of the permitting program is adequate public information and participation. However, due to the complex nature of the permit, it was necessary to prepare a summary in plain language, and present the same to environmental organizations so that meaningful comments could be generated. TCG was engaged by the U.S. EPA to prepare the technical summary (in English and Spanish) and present the same to community and environmental groups.

        Soft Drink Manufacturing Company, Puerto Rico

Work involved the performance of a feasibility and bench-scale treatability study to assess the possibility of using ozone to remove color from process wastewaters. Client was a major  concentrate manufacturing plant, serving most of the North American, South American and European markets.


Site Assessments



Program Management


Municipal Water and Wastewater

Introduction to Technical Consulting Group