MULTI INCREMENT Sampling Approach to PCB

MULTI

® INCREMENT

Sampling Approach to PCB Release Response Assessment † Fehér,

† Chong,

‡ Shacat,

Domonkos Robert Joseph †Environmental Science International Inc., 304 Uluniu St. Suite 304, Kailua, HI 96734, USA ‡ Grace Pacific LLC, 949 Kamokila Blvd, Suite 100, Kapolei, HI 96707, USA MULTI INCREMENT® is a registered trademark of EnviroStat, Inc.

1. Introduction

3. Site Assessment

During demolition activities associated with the shutdown of the Grace Pacific Lower Makakilo Aggregate Processing Facility on O‘ahu, Hawai‘i, PCB contaminated oil was released from up to three capacitors. The objectives of ESI’s release response and remedial actions were to

4. The Stats Initial Removal 20 cubic yards. Disposal Cost:

Motor Control Center

Initial Assessment

(1) Assess/delineate the extent of PCB contamination

Crushed Capacitor

Dexsil CHLOR-N-OIL < 50 ppm

(2) Remediate/manage/dispose of PCB waste. The investigation was designed to comply with Toxic Substances Control Act [TSCA] regulations, USEPA Region 9 policy (discrete sampling), as well as Hawai‘i Department of Health [HDOH] - Hazard Evaluation and Emergency Response Office MULTI INCREMENT® sampling [MIS] guidance.(a)

2. MULTI INCREMENT ® Sampling Methodology Designate Decision Units

PCB Spill

> 50ppm

The Spill Area – after Removal of Gross Contamination

Graded Site

TSCA

MIS

Discrete samples in 31 locations within the spill area were designated according to TSCA referenced guidance(d) using a hexagonal sample grid. The initial spill area was designated based on visual evidence of contamination and reports from site workers. Soil samples were collected into 4oz glass jars and sent to a laboratory for Aroclor analysis by EPA Method 8082. Removal was based on discrete sample results in line with the current EPA Region IX interpretation of TSCA.

All boundary concentrations < 0.30 mg/kg

Rapid field screening of PCBs by EnzymeLinked Immunosorbent Assay [ELISA] was conducted to delineate decision unit [DU] boundaries. This approach eliminates concerns of diluting(e) the initial spill with soil that is not impacted. The field screening indicated that the size of the spill area could be reduced by about 20%. The four boundary DUs (with 100 increments each) were sampled and analyzed to make sure the readjusted boundaries were clean.

The average concentrations for the 31 initial discrete samples was 30 mg/kg ( MS

3 𝐶𝑑 𝐹𝐹 2 = 𝑀𝑆

c - mineralogical factor I - liberation factor f - shape factor g - granulometric factor d - maximum particle size ML - mass of the lot (g) MS - mass of the sample (g)

Goal: Keep Field Sampling Error on the Order of Laboratory Error Keep Total Error Below DQOs

D. Confirmation Sampling

The sampling approach using MIS can follow multiple designs. Without the need to follow the EPA Region 9 interpretation of TSCA, iterations of field screening and laboratory analysis of MIS samples or a pure MIS approach may be considered. Splitting certain sites into 4-8 or more decision units may be reasonable to minimize disposal cost and to comply with the TSCA anti-dilution clause.(e) For this project field screening together with a oneDU confirmation sampling approach was chosen for the relatively small spill area.

O U T

Done when TSCA: < 1.0 mg/kg < 10 mg/kg + cover for all samples Hawai‘i Department of Health: < 1.1 mg/kg for each DU

B. Confirmation Sampling

TSCA (40 CFR §761.61)

MIS (HDOH TGM)

Number and location of discrete samples are designated according to Field Manual for Grid Sampling of PCB Spill Sites to Verify Cleanup(d), a 1986 publication that utilizes a hexagonal sample grid. The number of samples depends on the size of the contaminated area. The design assumes uniform distribution of contamination. A single point sample result is assumed to represent the concentration of PCBs in the soil around it. Both assumptions are wrong, especially for PCB contaminated sites.(f)

Based on sampling theory and study data on heterogeneity for specific spill types. Designed to eliminate errors associated with mass reduction during sampling and laboratory processing. Number of individual increments within a Decision Unit is dependent on heterogeneity profile. Normally 30 to 100 increments are collected. The mass required for analysis is mainly dependent on particle size distribution in the soil sample.

Note that TSCA does not prohibit the use of MIS for PCB spill cleanup! Current EPA policy, however, rejects the use of MIS for TSCA sites. A Memorandum of Understanding [MOU] that outlines a technical and regulatory pathway for the incorporation of MIS methodology under TSCA is currently being pursued between HDOH and EPA Region 9. References:

C. Removal

For training courses on MULTI INCREMENT® Sampling contact Charles Ramsey of ENVIROSTAT (http://www.envirostat.org). (a) State of Hawai‘i Department of Health. 2015. Technical Guidance Manual for the Implementation of the Hawai‘i State Contingency Plan. (http://www.hawaiidoh.org) (b) USEPA. 2002. RCRA Waste Sampling Draft Technical Guidance. EPA/530/D-02/002. (c) Gy, P. 1998. Sampling for analytical purposes. John Wiley & Sons. (d) USEPA. 1986. Field Manual for Grid Sampling of PCB Spill Sites to Verify Cleanup. EPA-560/5-86-017. (e) TSCA 40 CFR 761.1(b)(5). (f) State of Hawai‘i Department of Health. 2015. SmallScale Variability of Discrete Soil Sample Data, Field Investigation of Discrete Sample Variability.

Acknowledgments:

The authors would like to thank Marvin Heskett for his assistance with PCB field analyses, ALS Global in Kelso, WA, for MIS processing and laboratory analyses, and all ESI and Grace Pacific staff involved in the field activities.