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HomeMy WebLinkAboutDTS-07-074 - Impact of Disposal for Salt Contaminated Soils on Reconstruction ProjectsREPORT Report To: Councillor Berry Vrbanovic, Chair, and Members of the Finance and Corporate Services Committee Date of Meeting: May 7th, 2007 Submitted By: Larry Lynch, Manager of Engineering Infrastructure Prepared By: M. Henderson, Supervisor of Engineering Asset Management Wards} Involved: All Date of Report: April 23, 2007 Report No.: DTS 07-074 Subject: Impact of Disposal for Salt Contaminated Soils on Reconstruction Projects RECOMMENDATION: THAT staff be directed to defer the Clark Street Project's 2007 tendering and construction component until the 2008 construction season. THAT staff be directed to transfer the funding from the 2007 Clark Street budget allocation x$2,167,000} into the uncommitted infrastructure account, to be allocated as necessary to the remaining 2007 reconstruction projects at the tender award stage in order to provide funding for the new disposal costs associated with salt contaminated soils on the remaining 2007 reconstruction projects THAT staff be directed to endorse continued participation with the Region of Waterloo's initiative to investigate and report on all feasible future long term options for disposal of salt contaminated material. BACKGROUND: The reconstruction of a roadway and installation of new underground services typically involves the excavation and off site removal of surplus native soils and replacement of these soils with imported, granular materials meeting established engineering specifications. Most typically this involves disposal of soils contaminated with heavy metals, hydrocarbons and/or other chemical contaminates which may have migrated from gas stations or industry near the road allowance. If geotechnical testing confirms the presence of these contaminates then guidelines under the Environmental Protection Act stipulate the removal and disposal to a licensed off-site facility. One of the substances which was identified in the Environmental Protection Act as a contaminant is road salt. Typically a portion of the road salt applied for de-icing purposes remains within the soil underneath the asphalt layer within the road granulars and accordingly the salt content can exceed the allowable limit for inert fill. The updated provincial standards place new limits on salt-related contaminates in soil and ground water and as such the definition of "inert fill" now excludes soils with modest salt contamination. As a result of this tightened definition local aggregate pits have begun to refuse any material which does not meet the classification of inert fill in order to remain in compliance with the aggregate license conditions issued by the Ministry of Natural Resources. It should be noted that although most road allowance soils do have salt concentrations which exceed the "inert-fill" criteria, they do not pose a risk to human health, to wildlife or to the natural environment. The salt content threshold that is being applied for the disposal of salt- contaminated soils is based on levels above which plant growth may be inhibited. Some plant species are less salt tolerant than others and the limits have been prescribed according to the more sensitive plant species. As such the level of salt "contamination" in excavated road allowances is not a significant environmental or health concern. Advanced geotechnical boreholes and testing on the City of Kitchener's 2007 reconstruction projects confirmed the moderately elevated salt contamination on all of this year's scheduled projects. Projects which are being carried over from 2006, although not yet tested are expected to exceed the MNR guidelines for moderate salt contamination as well. REPORT: The impact on 2007 construction activities can be summarised into two categories -financial and process related. Engineering staff met with local area municipalities in late March of this year to discuss the possible ramifications and some potential solutions. A Regional report tabled in early April addressed some of these potential solutions as follows: 1) Discussion with Local area gravel pit operators to upgrade licences to accept salt- contaminated soils 2) Licensing municipally owned sites to accept salt-contaminated soils or for temporary storage/mixing and ultimate re-use of material as fill 3) Placement of excess material on future sites requiring fill also municipally owned. 4) Re-use at industrial/commercial properties 5) Licensing opportunities at existing Regional Landfill sites 6) Possible design alterations to minimise volume removals 7) Lobbying Provincial government officials to re-consider this position 8) Discussion and liaison with local area municipalities to pursue a co-ordinated long term approach City of Kitchener staff became aware of a developing issue late summer early fall in 2006 during consultant interviews for 2007 projects. The City of Kitchener subsequently advanced geotechnical testing on all the projects for 2007 specifically adding sodium absorption ratio material identification. We, along with the local industry were unsure of the specific ramifications resulting from the new provincial guidelines. When the local area aggregate pits began no longer accepting the "contaminated" material as inert fill the financial ramifications to all area municipalities came to the forefront. Our first real discussion concerning this development and possible financial consequence was at the Region in late March of 2007. It was at this meeting where most area Municipalities actively took part in this first discussion and agreed to continue meeting until a unified approach is achieved for both the short and long term. An immediate subsequent meeting was arranged and held with City of Kitchener staff to discuss some possible solutions for the immediate 2007 construction season. Several of the above listed solutions were discussed in order to minimize or in fact remove the potential 2007 financial impact to the corporation as follows: Use of existing industrial/commercial property requiring fill material Possible Solution: Discussion here centered around properties like our Joseph and Gaukel project which does require fill off the right-of -way. Prohibiting Factors: The problem was restrictions within the Act which prohibit transfer off the right-of-way as well there would be an unknown negative effect on the future potential land use and potentially the future property value. New development requiring fill material Possible Solution: Discussion here was centered around possible new roadway developments which require fill on the right-of-way. Prohibiting Factors: The problem with this solution was the adjacent zoning was typically residential and therefore not allowed under the legislation. Temporary storage and mixin_. aq t City owned facility Possible Solution: Discussion here was about a possible use of the existing Battler Road storage facility. Prohibiting Factors: The problem with this solution was licensing requirements and available space for volume of materials. Mana_ginq material on site Possible Solution: This option was suggested by our geotechnical consultant and involved burying the "contaminated" material in the deep excavations and hauling off the cleaner material from the deeper strata as this would be potentially clean fill and therefore acceptable to the aggregate pits. Prohibiting Factors: The problem with this solution was both with cost of on site material management and most importantly lack of available space on most typical municipal right-of- waysunder reconstruction. Disposal at a licensed facility Possible Solution: Specification changes within the Special Conditions of the construction contract and adding a specific item to the form of tender for material removal and disposal. Prohibiting Factors: Cost to projects which was not identified in the budget development because of timing of this issue. The final proposed solution was agreed to by staff as the only viable short term solution for the 2007 construction season. As such, Engineering staff have included a revised Special Provisions section in all construction contracts for 2007 projects which were tendered after the March Regional meeting. This revised specification is intended to address the disposal of excess "salt contaminated" material at a licensed facility. Presently this seems like the only option for 2007 projects until some of the other alternatives are fully investigated for feasibility long term. FINANCIAL IMPLICATIONS: The 2007 capital forecast was developed prior to the time that the industry brought the excess soil "salt-contamination" issue forward to the City The budget process as a result did not include these new disposal costs. The anticipated financial impact for salt contaminated soil disposal is approximately $3 million in 2007, excluding Clark Avenue, which is recommended for deferral in order to free up funding for the remaining projects. The $2,167,000 budget for Clark Avenue would be transferred to the uncommitted capital account until such time as the funds are required . The City maintains the triple-funded uncommitted capital account in part to provide for cost overruns associated with the clean up of contaminated soils on various infrastructure projects, given the difficulty in accurately estimating the cost on individual projects. Funds are transferred out of the account using the standard 23%/31 %/46% split. As indicated below, while the transfers recommended in this report can be accommodated with the deferral of Clark Avenue, they will all but exhaust the City's ability to fund any other costs beyond those identified in this report due to the low balance in the water component. This account is replenished annually through the budget process and a review of the funding model is scheduled for 2007. The projected balance in uncommitted capital is: Current Allocation for Balance Transfer of Salt (including Allocation to Clark Ave. Contaminated 2007 budget} Heins Ave. Funds Soil Net Balance C/C 871,904 (34,960) 498,000 (690,000) 644,944 Water 313,493 (47,120) 672,000 (930,000) 8,373 Sewer 2,509,446 (69,920) 997,000 X1,380,000) 2,056,526 3,694,843 (152,000) 2,167,000 (3,000,000) 2,709,843 CONCLUSION: The selection of Clark Avenue for deferral at this time was based on several factors. This project is quite large by length some 820 metres long and involves a significant volume of contaminated material removal. This project was scheduled for a late May tendering and has been complicated by a traffic calming initiative, potential significant storm sewer upgrades to the outlet which may require and Environmental Assessment in addition to an expanded scope of walkway upgrades to improve access to the neighbourhood. Stantec Consulting has been retained to complete the design and will ultimately oversee the reconstruction activities as well. Staff discussions determined this project as a good candidate for deferral based on the present financial restrictions caused by this new development. The continued participation in the Region of Waterloo initiative for salt contaminated soil disposal as well as internal staff led inquires should present the best long term solution for this challenge. Endorsement of these staff recommendations will allow the bulk of our 2007 construction projects to proceed as planned while minimizing the impact to our overall program for 2007. Larry Lynch, C.E.T. Manager of Engineering Infrastructure Mike Henderson, CET Supervisor of Engineering Asset Management