Services


CEQA/NEPA Compliance:

WJVA has prepared noise assessments for hundreds of environmental impact reports and statements.  Prepared to comply with State of California (CEQA) and federal (NEPA) requirements, these project documents describe the environmental setting, criteria for noise impacts, predicted noise exposures, and mitigation measures for noise impacts.

Noise Control Engineering:

WJVA provides consulting services in noise control for industrial facilities such as pump stations, water treatment plants, and electrical distribution/receiving yards.  The scope of work typically consists of ambient noise measurements, equipment noise level and frequency content measurements, prediction of project noise levels as proposed, assessment of compliance with the relevant noise standards, and development of mitigation measures.  The mitigation measures may include equipment noise emission specifications, enclosures, acoustical louvers and silencers, absorptive treatments, and noise barriers.  Our clients have included public agencies such as cities, counties, and water or public utility districts.

Roadway Improvement Projects:

WJVA offers traffic noise assessment services for roadway improvement projects, especially those requiring Caltrans approvals.  To meet current Caltrans requirements, WJVA uses the U.S. DOT Traffic Noise Model (TNM) Version 2.5 to describe traffic noise exposures.  This program allows digitizing of roadway geometry, barriers, and receiver locations for analysis of complex situations.  The TNM is routinely calibrated using on-site noise level measurements to ensure that the results reflect actual field conditions.  Additional ambient noise measurements are conducted to describe peak hour traffic noise levels.  Traffic noise impacts are evaluated in accordance with the Caltrans Traffic Noise Protocol, following the Caltrans templates.

Mitigation Monitoring:

Many projects are approved subject to conditions that require monitoring of noise to ensure compliance with the assumptions of environmental analyses, and with specific conditions of approval.  WJVA has always specialized in understanding and implementation of environmental noise standards, and applies that experience to monitoring project noise levels to ensure that mitigation has been achieved.  Mitigation monitoring may include noise and/or vibration measurements, and WJVA is well equipped to conduct such analyses.

Aviation Noise: 

WJVA provides a wide range of noise assessment and mitigation services to airport operators and aviation planners. Where noise monitoring is required, WJVA can deploy multiple long-term noise monitoring units to quantify aircraft and helicopter noise exposures. WJVA also has extensive experience working on numerous airport sound insulation projects throughout the county.