LA METRO Purple (D Line) Extension Transit Project – Section 1

Completion Date: 2014-Present; Expected Completion 2025

Client: Los Angeles County Metropolitan Transportation Authority (LA Metro)

Services: Air, Environmental Management and Consulting, Hazardous Materials Management, Noise & Vibration, Soil, Water

About this Project

Kroner Environmental works with LA Metro to create and facilitate a plan that includes better transit to connect more people to more places with Section 1 of the Purple (D Line) extension.

This project has included several water services. We started with ground assessment and groundwater investigations. We then formulated a solution and designed best management practices (BMPs) for this specific project, and trained prime and sub contractors. We designed, furnished, and operated a successful water system. Because of surface water discharge, our solution included running water treatment systems while managing groundwater, stormwater, and wastewater. Our solution included discharging sanitary sewer under industrial waste permits issued by the cities of LA and Beverly Hills, and pumping water out of the ground and treating it before pumping it back in. The systems we designed treat up to one million gallons of groundwater per day.

We oversaw statewide permitting for sanitary sewer discharges, groundwater discharge options, and stormwater. Monthly samples were reported and monitored for compliance, while weekly and periodic stormwater inspections were practiced to follow compliance.

We monitored and engineered noise control as well. This project included continuous monitoring stations throughout alignment, spot-check monitoring, and noise abatement. We continually gathered all complaints from nearby sensitive receptors such as schools, medical facilities, historic properties, museums, commercial buildings, and other quiet or sensitive areas and provided viable solutions for all constituents.

We secured permitting facilities (batch plants) to provide air services. Our air treatment systems were used to control odors from naturally occurring gasses at the site. We performed several inspections to monitor and report gasses along alignment buildings that were found at high levels (such as hydrogen sulfide and methane gas).

In terms of hazardous materials management and soil services, we encountered hazardous substances and contaminants during construction from a previous industrial project. These included substances such as asbestos, lead containing materials, and naturally occurring oil contaminated soils. We characterized the most sustainable options for disposal while following all needed compliance. We carried out LA Metro’s Green Construction Policy (GCP) mitigation monitoring and reporting programs.