Distribution of Selected Volatile Organic Compounds Determined with Water-to-Vapor Diffusion Samplers at the Interface Between Ground Water and Surface Water, Centredale Manor Site, North Providence, Rhode Island, September 1999

Open-File Report 00-276

By Peter E. Church, Forest P. Lyford, and Scott Clifford

ABSTRACT

Volatile organic compounds are present in soils and ground water at the Centredale Manor Superfund Site in North Providence, Rhode Island. In September 1999, water-to-vapor diffusion samplers were placed in the bottom sediments of waterways adjacent to the site to identify possible contaminated ground-water discharge areas. The approximate12-acre site is a narrow stretch of land between the eastern bank of the Woonasquatucket River, downstream from the U.S. Route 44 bridge and a former mill raceway. The samplers were placed along a 2,250-foot reach of the Woonasquatucket River, in the former mill raceway several hundred feet to the east and parallel to the river, and in a cross channel between the river and former mill raceway.

Volatile organic compounds were detected in 84 of the 104 water-to-vapor diffusion samplers retrieved. Trichloroethylene and tetrachloro-ethylene were the principal volatile organic compounds detected. The highest vapor concentrations measured for these two chemicals were from diffusion samplers located along an approximate 100-foot reach of the Woonasquatucket River about 500 feet downstream of the bridge; here trichloroethylene and tetrachloroethylene vapor concentrations ranged from about 2,000 to 180,000 and 1,600 to 1,400,000 parts per billion by volume, respectively. Upstream and downstream from this reach and along the former mill raceway, trichloroethylene and tetrachloroethylene vapor concentrations from the diffusion samples were generally less than 100 parts per billion by volume. Along the lower reaches of the river and mill raceway, however, and in the cross channel, vapor concentrations of trichloroethylene exceeded 100 parts per billion by volume and tetrachloroethylene exceeded 1,000 parts per billion by volume in several diffusion samples. Although diffusion sample vapor concentrations are higher than water concentrations in surface waters and in ground water, and they should only be interpreted qualitatively as relative values, these values provide important information as to potential discharge areas of contaminants. 

TABLE OF CONTENTS

Abstract

Introduction

Use of Vapor Diffusion Samplers for Monitoring of Volatile Organic Compounds 

Volatile Organic Compounds Detected in Vapor Diffusion Samples 

References

PLATE

1. Map showing location of study area, data collection sites, and total concentrations of volatile

organic compounds from vapor diffusion samplers, and graphs of trichloroethylene and

tetrachloroethylene concentrations at collection sites, Centredale Manor Site,

North Providence, Rhode Island, September 1999

FIGURES

1. Graph showing gage height of Woonasquatucket River, U.S. Route 44 bridge,

North Providence, Rhode Island, September 1999

TABLES

1. Minimum reporting limits for target volatile organic compounds, Centredale Manor,

North Providence, Rhode Island, September 1999

2. Concentrations of volatile organic compounds in vapor diffusion samplers at Centredale Manor,

North Providence, Rhode Island, September 1999