Hazardous Materials Technical Memorandum

Transcription

1 Hazardous Materials Technical Memorandum Southeast Extension Project Lincoln Station to RidgeGate Parkway Prepared for: Federal Transit Administration Prepared by: Denver Regional Transportation District May 2014

2 Table of Contents Page No. Chapter 1.0 Introduction Background Regulatory Setting Chapter 2.0 Alternatives Evaluated Chapter 3.0 Affected Environment Chapter 4.0 Impact Evaluation No Action Preferred Alternative Chapter 5.0 Mitigation List of Appendices Appendix A: EDR Report, July 2012 List of Figures Figure 1-1 FasTracks Plan Figure 1-2 Study Area Figure 2-1 No Action Alternative Figure 2-2 Preferred Alternative Figure 3-1 OPS Listed Sites Within Study Area List of Tables Table 5-1: Summary of Hazardous Materials Impacts and Mitigation TOC-1

3 Chapter 1.0 Introduction This Technical Memorandum was prepared in support of the Southeast Extension Environmental Assessment initiated by RTD in RTD prepared the Southeast Corridor Extension Environmental Evaluation (EE) in March 2010 for the proposed action. The EE presented the findings of the Modified Phase I Environmental Site Assessment (MESA) prepared for the proposed action in November For the current EA effort, a desktop hazardous material data search was conducted in 2012 (see Appendix A) to update and supplement information in the EE and Phase I MESA. This Technical Memorandum documents the results of the 2012 desktop data search. 1.1 Background In November 2004, Regional Transportation District (RTD) voters approved the FasTracks initiative to expand and improve public transit service within the Denver Metropolitan Region (Metro Region). The comprehensive FasTracks Plan, which formed the basis of the FasTracks ballot initiative, includes the construction and operation of new fixed-guideway transit lines, improved bus service, and park-n-rides throughout the Metro Region. The Southeast Extension was included in the RTD FasTracks program and is in the currently adopted Regional Transportation Plan (RTP). The fixed-guideway transit elements (rail and bus rapid transit) of the FasTracks Plan are shown in Figure 1-1. The proposed action is to extend transit service south into the City of Lone Tree to serve the increased population and employment generated by planned development in the City of Lone Tree. The Southeast Extension study area is located in northern Douglas County, and includes the City of Lone Tree and portions of Highlands Ranch and the Town of Parker. It begins at the existing end-of-line Lincoln Avenue LRT station and extends south along I-25 to the I- 25/RidgeGate Parkway interchange. It includes areas of planned development south of Lincoln Avenue on the east and west side of I-25 (see Figure 1-2). 1.2 Regulatory Setting The presence or release of hazardous materials on construction sites can expose workers, adjacent residents, and other ecosystems to contaminants that may compromise their health. As a result, evaluation of the potential for transit projects to impact, or be impacted by, hazardous materials are essential. Encountering contamination during construction can impact the cost-effectiveness of the project and can result in long-term costs associated with sampling and remediation. Prior to acquiring properties, it is important for RTD to understand the environmental risks and liabilities. The term hazardous materials is an all-inclusive term for materials that are regulated as a solid waste, hazardous waste, or other wastes contaminated with hazardous substances, radioactive materials, petroleum fuels, toxic substances, and pollutants. 1-1

4 Figure 1-1 FasTracks Plan 1-2

5 Figure 1-2 Study Area 1-3

6 Chapter 2.0 Alternatives Evaluated This technical memorandum evaluates the effects of two alternatives a No Action Alternative and the Preferred Alternative. These alternatives are described below. The No Action Alternative assumes no new improvements would be constructed other than currently committed projects identified in the 2035 RTP. This alternative includes the existing bus routes in the area and a new bus route (Route 411) connecting Parker and the Lincoln Station along RidgeGate Parkway. The CDOT project that includes I-25 widening from RidgeGate Parkway to C-470 is also included as part of this alternative. Figure 2-1 shows the No Action Alternative. Figure 2-1 No Action Alternative 2-1

7 The Preferred Alternative includes a 2.3-mile, double-track light rail extension that runs south from the existing Lincoln Station along the west side of I-25, crosses to the east side of I-25 just north of the Sky Ridge Medical Center, and continues south to the RidgeGate Parkway interchange. This alternative provides three new stations. The Sky Ridge Avenue Station across from the Sky Ridge Medical Center and the Lone Tree City Center Station situated in the core of the RidgeGate planned development are both planned as kiss-n-ride stations without parking. A new end-of-line station at RidgeGate Parkway would provide a park-n-ride. Access to the RidgeGate Station would be provided from Havana Street via two access roads. All three stations would accommodate feeder bus service. The light rail tracks would be grade separated via an overpass where they cross Lincoln Avenue, I-25, and RidgeGate Parkway. One at-grade crossing is proposed on a minor roadway near the Sky Ridge Station. Two parking design options are being considered at the RidgeGate Station, as described below: Option 1: This option would provide a 1,300-space surface parking lot on opening day (2019). In 2035, the surface parking lot would be replaced with two parking structures that would accommodate a total of 2,100 parking spaces. The southern parking structure would consist of four levels and the northern parking structure would consist of three levels. Option 2: This option would provide one 4-level, 1,300-space parking structure on opening day (2019). In 2035, an additional 3-level parking structure would be built north of the first structure that would provide 800 parking spaces, for a total of 2,100 spaces. The two parking structures in 2035 would be the same design and configuration under both parking options. The Preferred Alternative is shown on Figure

8 Figure 2-2 Preferred Alternative 2-3

9 Chapter 3.0 Affected Environment In support of the EE, a Modified Phase I Environmental Site Assessment (MESA) was prepared in 2008 by LT Environmental Inc. Using criteria presented in the RTD Environmental Methodology Manual, sites identified during the data collection process were ranked as High, Moderate, Low, or Negligible, based on their potential to impact the project. Site ranking criteria included distance from the centerline of the proposed alignment or stations; use of hazardous substances; the data obtained in the file reviews; and the predicted depth and direction of groundwater flow, per RTD s 2006 Environmental Methodology Manual. Based on review of the Phase I MESA, no moderate or high-ranked sites with the potential to impact the project were identified within the Study Area in the EE. As part of the EA, a regulatory database report was obtained in July 2012 from Environmental Data Resources (EDR) and records at the Division of Oil and Public Safety (OPS) were reviewed to re-evaluate the potential for the project to impact, or be impacted by, hazardous materials (see Appendix A). Based on the 2012 EDR report, there are no listed sites within the regulatory search distance (up to one mile) with the potential to impact the project. However, EDR listed six sites as orphan sites within the vicinity of the project. The term orphan sites means EDR could not pinpoint the exact location of the sites with the listed addresses. Review of the listed addresses indicated the sites were located over one mile away from the proposed improvements. Therefore, these sites do not pose a risk to the project. According to the OPS database, two listed sites were identified within one mile of the proposed improvements that were not identified in the Phase I MESA prepared for the EE. These sites are described below and shown on Figure 3-1. Diamond Shamrock #1189 This site is located at 9945 South Oswego Street, approximately one mile east of the proposed improvements. This facility is listed as having three in-service underground storage tanks (USTs) that are used to store gasoline and diesel. The tanks were installed in February There have been no reported violations. Therefore, this site is unlikely to pose a risk to the project. 7-Eleven #34057 This site is located at East Oswego Street, less than one mile east of the proposed improvements. This facility is listed as having two in-service USTs that are used to store gasoline and diesel, and one permanently closed UST that was used to store diesel. A violation was reported in August 2009 and in October 2009 OPS granted no further action due to low risk based screening levels. Therefore, this site is unlikely to pose a risk to the project. 3-1

10 Southeast Extension Figure 3-1 OPS Listed Sites Within Study Area 3-2

11 Chapter 4.0 Impact Evaluation The Phase I MESA prepared for the EE was reviewed to help determine if any hazardous materials sites were located in proximity to the project. The analysis evaluated the impact of hazardous materials sites on the alternatives. This information was used to identify potential areas of concern for either construction or land acquisition. In addition, information collected in July 2012 from the EDR report and OPS was used to identify potential impacts not identified in the Phase I MESA prepared for the EE. 4.1 No Action Under the No Action Alternative, there would be no direct, indirect, construction-related, or cumulative impacts to or from hazardous materials sites from the Southeast Extension project. 4.2 Preferred Alternative No sites of potential concern have been identified that would impact or be directly impacted by the Preferred Alternative. No indirect or cumulative impacts are anticipated. However, it is possible that undocumented or unanticipated hazardous materials could be encountered during ground-disturbing construction activities. 4-1

12 Chapter 5.0 Mitigation Table 5-1 summarizes potential impacts resulting from the Preferred Alternative and lists measures that RTD will undertake to mitigate impacts. Table 5-1: Summary of Hazardous Materials Impacts and Mitigation Summary of Potential Impacts from Preferred Alternative Direct Impacts No impacts Indirect Impacts No impacts Construction Impacts Potential for hazardous materials to become exposed during construction Cumulative Impacts No impacts No mitigation needed. No mitigation needed. Proposed Mitigation Prepare a Materials Management Plan to address the potential to encounter contaminated soil and groundwater. Complete an asbestos survey and a lead-based paint survey on structures proposed for demolition, if applicable. Prepare and implement a Health and Safety Plan to protect worker health and safety. Comply with Occupational Safety and Health Administration requirements for construction workers who may be exposed to hazardous materials. Follow CDOT 250 specification for hazardous materials when on CDOT right-of-way. Implement construction BMPs in accordance with Stormwater Pollution Prevention Plan. BMPs may include secondary containment areas for refueling construction equipment, berms or ponds to control runoff, and a monitoring program to test stormwater for contaminants prior to discharge from the construction site. No mitigation needed. 5-1