[Code of Federal Regulations]
[Title 40, Volume 28]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR761.130]

[Page 670-671]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 761--POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, 
DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS--Table of Contents
 
                   Subpart G--PCB Spill Cleanup Policy
 
Sec. 761.130  Sampling requirements.

    Postcleanup sampling is required to verify the level of cleanup 
under Sec. 761.125(c) (2) through (4). The responsible party may use any 
statistically valid, reproducible, sampling scheme (either random 
samples or grid samples) provided that the requirements of paragraphs 
(a) and (b) of this section are satisfied.
    (a) The sampling area is the greater of (1) an area equal to the 
area cleaned plus an additional 1-foot boundary, or (2) an area 20 
percent larger than the original area of contamination.
    (b) The sampling scheme must ensure 95 percent confidence against 
false positives.
    (c) The number of samples must be sufficient to ensure that areas of 
contamination of a radius of 2 feet or more within the sampling area 
will be detected, except that the minimum number of samples is 3 and the 
maximum number of samples is 40.
    (d) The sampling scheme must include calculation for expected 
variability due to analytical error.
    (e) EPA recommends the use of a sampling scheme developed by the 
Midwest Research Institute (MRI) for use in EPA enforcement inspections: 
``Verification of PCB Spill Cleanup by Sampling and Analysis.'' Guidance 
for the use of this sampling scheme is available in the MRI report 
``Field Manual for Grid Sampling of PCB Spill Sites to Verify Cleanup.'' 
Both the MRI

[[Page 671]]

sampling scheme and the guidance document are available from the 
Director, Environmental Assistance Division (7408), Office of Pollution 
Prevention and Toxics, U.S. Environmental Protection Agency, Room E-
543B, 1200 Pennsylvania Ave., NW., Washington, DC 20460, Telephone: 
(202) 554-1404, TDD: (202) 544-0551. The major advantage of this 
sampling scheme is that it is designed to characterize the degree of 
contamination within the entire sampling area with a high degree of 
confidence while using fewer samples than any other grid or random 
sampling scheme. This sampling scheme also allows some sites to be 
characterized on the basis of composite samples.
    (f) EPA may, at its discretion, take samples from any spill site. If 
EPA's sampling indicates that the remaining concentration level exceeds 
the required level, EPA will require further cleanup. For this purpose, 
the numerical level of cleanup required for spills cleaned in accordance 
with Sec. 761.125(b) is deemed to be the equivalent of numerical cleanup 
requirements required for cleanups under Sec. 761.125(c) (2) through 
(4). Using its best engineering judgment, EPA may sample a statistically 
valid random or grid sampling technique, or both. When using engineering 
judgment or random ``grab'' samples, EPA will take into account that 
there are limits on the power of a grab sample to dispute statistically 
based sampling of the type required of the responsible party. EPA 
headquarters will provide guidance to the EPA regions on the degree of 
certainty associated with various grab sample results.

[52 FR 10705, Apr. 2, 1987, as amended at 60 FR 34465, July 3, 1995]