Tidewater Pipeline Gasoline Spill

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Two thermos Oxidation units and piping.
Taken by: Gary Lee, Ecology 
Date: 08/29/00

Summary Information

Date of Incident:  
Friday, July 21, 2000, 5:40 pm

Location:  
Along the fence line of the Chevron Pipeline Facility in Pasco, (refer to provided general location map)

Product/Quantity:  
Estimate (as of 8/02/00) - a minimum of 8,000 gallons of gasoline  

Cause:  
Hole in transfer pipeline between the  Tidewater and Chevron facility. The reason for the hole is still under investigation.
 

Photographs

Maps/Drawings

News Articles

  

Summary Information 

This spill was due to a leak from a 6 inch pipeline owned by Tidewater. The pipeline is used to carry gasoline from Chevron over to Tidewater. Tidewater discovered a significant discrepancy between the amount of gasoline sent by Chevron and the amount received for the last several transfers. The Tidewater operators decided to conduct a stand up test (charged the gasoline in the line to 172 psi and looked to see if it would hold the pressure) to identify if there may be any problems in the pipeline. The test was conducted five times due to the lack of proper testing procedures. On the 5th test a Tidewater person who was over at the Chevron end of the pipeline smelled the strong odor of gasoline and found the wet spot in the sand. Tidewater exposed the section of the and discovered a hole (1/4" to 3/8" approx.) in the pipeline. Ecology is still in the process of investigating the cause of the incident.

 

Update  9-06-00 p.m.

  • Tidewater has provided information confirming that the site is stable.

  • Water samples from down gradient wells 9 and 10 remain clean and the recovery system will prevent further migration. 

  • The long term cleanup will continue under the guidelines in The Model Toxics Control Act, Cleanup Regulation, Chapter 173-340 WAC.

 

Update  8-29-00 p.m.

  • Second 500cfm Thermal Oxidation Unit is up and running They are now pumping free product from 5 wells. 

  • 3 of the 5 wells are also being used for vapor extraction. 

  • They will be expanding their recovery operation by adding one more pump with vapor extraction capability to another one of the existing wells. 

  • Today Tidewater sampled the outlying wells. Tidewater is optimistic that they will be able to demonstrate containment (confirm that the gasoline has stopped migrating toward the Snake River) by the end of the week. 

  • Once the spilled gasoline has been contained, the site will be turned over to Ecology's Toxics Cleanup Program for long term remediation oversight.

Update  8-11-00 noon

Currently 12 wells have been drilled at the site (well # 12 is being completed today).

Four of the wells (# 7, 8, 9 and 10) continue to show no visible gasoline in field testing. The analysis of two lab samples from these "clean" wells will be back Monday and two more will be back on Wednesday to tell us whether any gasoline constituents are in the water. If they are clean, we will be out of the emergency phase of this event.

The 11th and 12th wells were both drilled UP-gradient of the release site. Field testing of number 11 (150-feet upgradient) shows it is clean so far. But number 12 is much closer and is likely to have some gasoline.

Four pumps have been or are being plumbed today as part of an automatic pumping system. The gasoline and water will be stored in a 20,000 gallon storage tank that is already on-site. We expect to see a 50/50 mix of water and gasoline, gradually turning to mostely water.

Next week we will be able to operate the vapor extraction system.

Update 8-8-00 4:00pm

Efforts to characterize the extent of the contaminate plume continues. As of August 8th a total of 7 monitoring wells have been installed at the site. Free product is being pumped and removed from the ground water. A soil vapor extraction system is operating.

 

Update 8-4-00 4:00pm
Four monitoring wells have been installed. Efforts continue to characterize the contamination. A pneumatic pump is being used to remove gasoline from the ground water. The investigation into the cause and volume spilled is still under way.

 

Update 8-4-00 10:00am
Water sampling at Well #2 - located 50 feet down gradient from the release site (south of the release site) shows 1 ft 6 in of gasoline floating on the ground water.

They are in the process of punching well # 3. This well will be located 50 feet west of the initial point of release. ( Well #1)

Update 8-3-00 4:30pm

A 85 foot deep well was drilled, ground water was hit at 82 feet. Gasoline was found floating on the ground water. Further site characterization is under way, including the drilling of a well down-gradient from the spill site to see if the gasoline has migrated.