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NRC Environmen Services 1810 East James Street Pasco, WA 99301 telephone: 509.316.6701 facsimile: CHANGE NOTICE To: Kittitas County Re: Septage Application Project Date: May 13, 2019 Change Notice No. 01 Description: "Recipe" and Means & Methods Change Submitter(s): Shawn Estrada & Russell Morgan NRC Environmental Services (NRC) respectfully submits this Change Notice #01, Recipe and Means & Methods Change pursuant to Section 12, Modifications, subsection 12.2. The change notice is for impacts of the increased lime required to balance the pH for each load of septage and the change to the means and methods utilized by NRC to mix/ "slurry". These two factors, l) increase volume of lime 2) change in methodology, have had a significant impact on the project's production and associated cost. The following is NRCs analysis of how these items are affecting the project and its production rates. Lime mixture recipe provided during the bidding process was 50 pounds of lime per 1,000 gallons. This recipe has proven to be insufficient to elevate and maintain a pH level of 12 or more for 30 minutes in a batch as required. While the original recipe was a mixture at 50# of lime per 1,000 gallons, actual conditions show the mixture to be consistently higher at 83 pounds per 1,000 gallons to 133 pounds per 1,000 gallons ( a 66%-266% increase). The increased amount of lime required to attain and maintain the required pH balance of 12 for 30 minutes have led to increased material, labor and equipment costs to mix the additional volume. 2. The use of lagoon water has increased the number of pH failures by 50-100%, which in turn increases cycle time by 50% to 100% or more. Fresh water mixing has produced no failures in any loads based on NRC's mix recipe of 83 pounds per 1,000 gallons. 3. Due to the increase work load of having to clear pumps of lagoon "cake", longer cycle time for pumps to slurry a batch of lime with lagoon water, & the increase in the quantity of of lime to be added to each batch, it has been necessary to add an additional technician has been added to the project for the use of lagoon water.