PG&E Richmond-to-Pittsburg Pipeline
Section 2-III Air Quality
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SETTING

The pipeline corridor and the Hercules Pump Station are located in Contra Costa County which is under the jurisdiction of the Bay Area Air Quality Management District (BAAQMD). The Air District covers all or part of 9 counties in the San Francisco Bay region, and the airshed has been designated by the California Air Resources Board (ARB) as nonattainment of the Federal and State ambient air ozone standards, as well as nonattainment of the state PM-10 standard. Most of the rest of California also does not meet the state PM10 standard. The Bay Area region has been designated as attainment or unclassified for State and Federal standards for the other criteria pollutants: carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. Ambient air measurements over the past five years at four monitoring stations in Contra Costa County have shown occasional exceedances of the State and Federal ozone standards and of the State PM-10 standard.

The Hercules Pump Station is the only portion of the existing facility that generates measurable air pollutant emissions. The pump station includes two fuel oil heating units that have maximum heat input rates of 30 million BTU/hr. each. The heating units have BAAQMD air permits that allow the use of natural gas, number 2 fuel oil (diesel), or number 6 fuel oil (Bunker C). In the past, these heating units have used natural gas exclusively. Other equipment at the pump station with the potential to emit air pollutants include two diesel firewater pumps. The pumps are operated only for short time periods during monthly tests and if there is a fire emergency. Therefore, routine emissions from the firewater pumps are negligible. The pump station contains storage tanks for fuel oil and diesel fuel. Emissions from the tanks are negligible because of the relatively low volatility of the stored liquids.

AIR QUALITY IMPACT DISCUSSION

The sale of the Pipeline is based on its current CPUC-approved use, which is the transport of oil, petroleum and related products through the pipeline, and it is conditioned on the securing of the necessary rights of way for a 4,000-foot replacement section of the pipeline. Air quality impacts are discussed below for both the construction of the 4,000-foot pipeline replacement section and for operation of the pipeline project.

• The proposed action would not conflict with or obstruct the implementation of air quality plans in the BAAQMD, since all air pollution emission sources would be operated within permitted limits. The BAAQMD is revising their Air Quality Attainment Plan (AQAP) for the region and will submit the Plan to EPA Region 9 sometime in 2001. In the revised AQAP, permitted emission sources for this project are already included. Therefore the project will not be in conflict with the AQAP. Although the oil heaters at the Hercules Pump Station have used mostly natural gas as fuel in the past, they may use more fuel oil in the future. The existing air permits allow unlimited use of either natural gas or fuel oil, and fuel oil has been used before during certain times. Therefore, switching back to fuel oil will result in a less than significant impact.
  
  
• During construction of the 4,000-foot Martinez replacement section of the pipeline, there would be a temporary increase in the following criteria pollutant emissions:
  
  
  • PM-10 fugitive dust emissions during clearing, boring, and trenching operations

  • Exhaust emissions from construction equipment, including the criteria pollutants carbon monoxide, sulfur dioxide, nitrogen oxides and PM-10
  
  

  Fugitive dust emissions from construction activities would cause increases in ambient air particulate matter concentrations at receptors near the pipeline corridor. Construction dust is composed primarily of large particles that settle out of the atmosphere with increasing distance from the source. In general, construction dust would result in more of a nuisance than a health hazard. About one-third of the dust generated by construction activities consists of smaller size particles (PM-10) in the range that can be inhaled by humans, although these particles are generally inert. Persons with respiratory diseases who may be immediately downwind of the construction activities could be sensitive to this dust. Therefore, the short-term PM-10 air quality impacts from fugitive dust during construction would be significant unless mitigation measures prescribed by BAAQMD are implemented.

  Although exhaust emissions from construction vehicles are much lower than fugitive dust emissions, some of them (NOx and VOCs) contribute to the formation of ozone, a nonattainment pollutant, and fine particulate matter from exhaust emissions would contribute to ambient air PM-10 levels. Thus, short-term ozone impacts would be significant, and PM-10 impacts would be significant at locations near the construction site unless mitigation measures are adopted to reduce exhaust emissions.

  Impact III.1: Emissions from construction-related activities would cause a temporary increase in local particulate matter concentrations.

  Mitigation Measure III.1: SPBPC shall implement the following fugitive dust control and emissions reduction measures during construction of the 4,000-foot pipeline replacement. These measures are prescribed by BAAQMD to ensure that construction impacts are less than significant, and they include:

  • Construction areas, unpaved access roads, and staging areas shall be watered at least twice daily during dry weather, or soil stabilizers shall be applied during active work.

  • Trucks hauling soil and other loose material shall either be covered, have at least two feet of freeboard, or be sprayed with water prior to arriving and departing from the construction site.

  • Construction vehicles shall use paved roads to access the construction site wherever possible.

  • Vehicle speeds shall be limited to 15 mph on unpaved roads and construction areas, or as required to control dust.

  • Paved access roads, parking areas, and staging areas at construction sites and streets shall be cleaned daily with water sweepers if excessive soil material is carried onto adjacent public streets.

  • A carpooling strategy shall be implemented for construction workers prior to commencing construction (during construction worker orientation and training).

  • Vehicles used in construction activities shall be tuned per the manufacturer's recommended maintenance schedule.

  • Vehicle idling time shall be minimized whenever possible.

  • The CPUC mitigation monitor shall monitor compliance with these measures during construction.
  
  

  Significance after mitigation: Less than significant.

• Operation of the project would not result in a significant cumulatively considerable increase of any criteria pollutant emission for which the region is in nonattainment. During operations, NOx emissions, which are the principal contributors to ozone, would be within permitted levels and would not result in measurable increases in ozone levels. However, during construction of the 4,000-foot replacement section, NOx and PM-10 emissions would be cumulatively significant.
  
  

  Impact III. 2: Emissions from construction-related activities would cause a temporary cumulatively significant increase in local NOx and PM-10 emissions.

  Mitigation Measure: Implement Mitigation Measure III.1

  Significance after mitigation: Less than significant.

• The project would not expose sensitive receptors to substantial pollutant concentrations. Even though there may be a slight increase in emissions over previous operations if fuel oil is used in the heaters instead of natural gas, the increase would be within allowed levels under the existing air permits. Since the heaters have operated previously for short periods of time with fuel oil, there would be no significant short-term impacts at sensitive receptors, which are near the pump station. There would be a slight increase in emissions at the pump station heaters over the long-term because of greater hours of fuel oil usage versus natural gas. The slight increase in long-term emissions would result in less than significant impacts at sensitive receptors near the pump station.
  
  
• The project would not create odors affecting a substantial number of people. There are no odor complaints with regard to the existing facility, and operations in the future are not expected to result in increases of odorous pollutant emissions.