Variance 61

STATE OF CALIFORNIA, PETE WILSON, Governor

PUBLIC UTILITES COMMISSION
505 VAN NESS AVENUE
SAN FRANCISCO, CA 94102-3298

April 2, 1998

Dean Shauers, Project Manager
Pacific Pipeline System, Inc.
12201 E. Arapahoe Road, C10
Englewood, CO 80112

RE: Variance Request #61 - Eliminate the 2-minute idling restriction for project trucks as stipulated in Mitigation Measure A-7 for Segments 3 and 5

Dear Mr. Shauers:

We have reviewed the above-referenced variance request and approve a modified version of your request (a substantial increased time for idling instead of total elimination of the idling requirement), based on the following factors:

This request has been submitted given the concern of excess engine wear due to repeated startups and shutdowns.

The CPUC Air Quality Specialist and Environmental Monitors on Segments 3 and 5 have been consulted to confirm the facts stated in Variance Request 61.

Mitigation Measure A-7 is based on a recommendation by the South Coast Air Quality Management District (SCAQMD) for reducing construction emissions (Table 11-3, Chapter 11, SCAQMD CEQA Air Quality Handbook).

Currently, when trucks arrive at the site, they sometime must wait in a queue, typically 2 trucks long, while another truck is loaded/unloaded. While waiting in the queue, the driver must shut off the engine in order to comply with the 2-minute idling restriction. When the queue moves forward, the driver must start the engine, move forward in the queue, and again shut off the engine. This queuing cycle typically repeats itself two times. Table 1 presents the emissions associated with this queuing cycle.

Table 2 presents the total continuous idling time that could occur without exceeding the total emissions presented in Table 1. The ultimate purpose of this mitigation, developed by SCAQMD, was to reduce the total emissions associated with construction activities in an Air Basin that is designated as Non-Attainment of air quality standards for all pollutants except sulfur dioxide. In order to achieve the ultimate goal of this mitigation, we agree to modify the requirement for idling. Based on the data in Table 2, we concluded that by increasing the idling restriction from two to ten minutes, no net increased air quality impact would occur.

Table 1 - Emissions Resulting from Queuing

Emissions	Emission Rates		Emissions during Queuing³		^{Total Emissions}
	^Idling1	^{Hot Start2}	^Idling	^{Hot Start}
^NOx	^{0.22 g/min}	^{1.00 g/start}	^{0.88 g}	^{2.00 g}	^{2.88 g}
^CO	^{0.67 g/min}	^{4.11 g/start}	^{2.68 g}	^{8.22 g}	^{10.90 g}
^ROC	^{0.27 g/min}	^{0.80 g/start}	^{1.08 g}	^{1.60 g}	^{2.68 g}

^{1. AP-42, Volume II, Table 1.7.3}
^{2. SCAQMD CEQA Manual, Table A9-5-K-4, CY 1997.}
^{3. Assuming two 2-minute idling periods and two hot starts.}

^{Table 2 - Idling Minutes}

^Emissions	^{Total Emissions}	^Idling ^{Emission Rate1}	^{Minutes of Continuous Idling}²
^NOx	^{2.88 g}	^{0.22 g/min}	^{13.1 min}
^CO	^{10.90 g}	^{0.67 g/min}	^{16.3 min}
^ROC	^{2.68 g}	^{0.27 g/min}	^{9.9 min}

^{1. AP-42, Volume II, Table 1.7.3}
^{2. Assuming no net increase air quality impact.}

^{The following measures shall be
implemented:}

^{- An idling restriction for project
trucks of 10 minutes shall be implemented and enforced.}

^{- All applicable mitigation measures
for the project shall be implemented at the subject
locations.}

^{- Implementation of this variance in
accordance with the provisions noted above shall be verified
on a random basis by a CPUC/ANF Environmental Monitor.}

Sincerely,

Andrew Barnsdale
Project Manager

cc: R. Borden, ANF
H. Rastegar, Aspen

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