Malburg Generating Station
Application for Certification6.0 Natural Gas Supply
6.0FACILITY CLOSURENATURAL GAS SUPPLY
6.1Gas Supply
The MGS will be fueled with pipeline quality natural gas. Natural gas will be delivered to the MGS project from an existing gas transmission pipeline, running under East Fruitland Avenue, owned and operated by the City. This pipeline is located approximately 1,100 feet from the proposed power plant site. A new, 1,100-foot long, ten-inch diameter service line to the power plant will be laid within the existing rights-of-ways of Seville and Fruitland Avenues. An additional 200 feet of pipeline will be laid within the existing power generating site.
The route of the new natural gas supply pipeline is shown in Figure 6.1-1. The tie-in to the power plant is shown in Figure 6.1-2.
Isolation valves are located approximately 1,250 feet upstream and 400 feet downstream of the preferred service connection to the existing pipeline, allowing isolation of the natural gas service in case of a problem. Pipeline vents are installed at each isolation valve to depressurize the line for maintenance or repair.
The natural gas pressure as delivered will be between 275 and 400 psig. Three new 50 percent natural gas compressors will be installed to boost the natural gas pressure to the minimum pressure of 378 psig required at the CTG inlets. Capacity controls will be used to control flow and compressor discharge pressure. Particulate matter and condensate will be removed from the fuel gas by individual fuel gas inlet scrubbers and a common outlet coalescing filter scrubber. The compressors will only be operated when needed.
6.2Pipeline Construction
The new natural gas pipeline will be buried with a minimum 36-inch cover. All pipe and welded field joints will be coated with the required material and cathodically protected against corrosion. The pipeline will be designed to Uniform Building Codes (UBC) seismic design criteria and in conformance with California Public Utilities Commission (CPUC) General Order No. 112 E and Title 49 CFR Part 192, Transportation of Natural and Other Gas by Pipeline.
6.3Alternative Natural Gas Service Routes
Two possible routes exist for providing gas service from the existing pipeline. Selection of the preferred route was based on the following criteria:
- Ability to interconnect to an available gas supply.
- Land uses on and adjacent to the pipeline route.
- Ability to minimize or avoid sensitive environmental resources.
- Traffic impacts.
- Room for additional pipeline in the streets right-of-ways.
6.3.1Alternative 1
Alternative 1 extends from the existing gas transmission line at the intersection of Fruitland Avenue and Seville Avenue, north along Seville Avenue to the proposed plant site. Compared to Alternative 2, it is less disruptive to traffic and less costly due to a shorter route to the MGS. Alternative 1 is the preferred route.
6.3.2Alternative 2
Alternative 2 extends from the existing gas transmission line at the intersection of Fruitland Avenue and Soto Street, north along Soto Street to 50th Street, then west along 50th Street to the proposed MGS. Soto Street has much higher traffic volumes than Seville Avenue, making this route more disruptive to traffic. This route is longer than Alternative 1 and would cost more to construct. Alternative 2 was rejected in favor of Alternative 1.
Additional details of the alternatives are presented in section 9.0, Alternatives.
6-1
K:\Reports\R1382 (Vernon-Combined Cycle)\AFC\6.0 Natural Gas Supply.doc10/24/18
Malburg Generating Station
Application for Certification6.0 Natural Gas Supply
6-1
K:\Reports\R1382 (Vernon-Combined Cycle)\AFC\6.0 Natural Gas Supply.doc10/24/18
Malburg Generating Station
Application for Certification6.0 Natural Gas Supply
6-1
K:\Reports\R1382 (Vernon-Combined Cycle)\AFC\6.0 Natural Gas Supply.doc10/24/18