Section 742.225 Demonstration of Compliance with Soil and Groundwater Remediation Objectives

Section 742

Section 742.225

Demonstration of Compliance with Soil and Groundwater Remediation Objectives

Compliance with soil and

groundwater remediation objectives is achieved if each sample result does not

exceed that respective remediation objective unless a person elects to proceed

under subsections (c), (d) and (e).

a)         Compliance with groundwater remediation objectives developed

under Subparts D through F and H through I shall be demonstrated by comparing

the contaminant concentrations of discrete samples at each sample point to the

applicable groundwater remediation objective.   Sample points shall be

determined by the program under which remediation is performed.

b)         Unless the person elects to composite samples or average

sampling results as provided in subsections (c) and (d), compliance with soil

remediation objectives developed under Subparts D through G and I shall be

demonstrated by comparing the contaminant concentrations of discrete samples to

the applicable soil remediation objective.

1)         Except as provided in subsections (c) and (d), compositing of

samples is not allowed.

2)         Except as provided in subsections (c) and (d), averaging of

sample results is not allowed.

3)         Notwithstanding subsections (c) and (d), compositing of

samples and averaging of sample results is not allowed for the construction

worker population.

4)         The number of sampling points required to demonstrate

compliance is determined by the requirements applicable to the program under

which remediation is performed

ons (c) and (d), averaging of

sample results is not allowed.

3)         Notwithstanding subsections (c) and (d), compositing of

samples and averaging of sample results is not allowed for the construction

worker population.

4)         The number of sampling points required to demonstrate

compliance is determined by the requirements applicable to the program under

which remediation is performed.

c)         If a person chooses to composite soil samples or average soil

sample results to demonstrate compliance relative to the soil component of the

groundwater ingestion exposure route, the following requirements apply:

1)         A minimum of two sampling locations for every 0.5 acre of

contaminated area is required, with discrete samples at each sample location

obtained at every two feet of depth, beginning at six inches below the ground

surface for surface contamination and at the upper limit of contamination for

subsurface contamination and continuing through the zone of contamination.

Alternatively, a sampling method may be approved by the Agency based on an

appropriately designed site-specific evaluation.  Samples obtained at or below

the water table shall not be used in compositing or averaging.

2)         For contaminants of concern other than volatile chemicals:

A)        Discrete samples from the same boring may be composited; or

B)        Discrete sample results from the same boring may be averaged.

3)         For volatile chemicals:

A)        Compositing of samples is not allowed.

B)        Discrete sample results from the same boring may be averaged.

4)         Composite samples may not be averaged.  An arithmetic average

may be calculated for discrete samples collected at every two feet of depth

through the zone of contamination as specified in subsection (c)(1)

e boring may be averaged.

3)         For volatile chemicals:

A)        Compositing of samples is not allowed.

B)        Discrete sample results from the same boring may be averaged.

4)         Composite samples may not be averaged.  An arithmetic average

may be calculated for discrete samples collected at every two feet of depth

through the zone of contamination as specified in subsection (c)(1).

d)         If a person chooses to composite soil samples or average soil

sample results to demonstrate compliance relative to the outdoor inhalation

exposure route or ingestion exposure route, the following requirements apply:

1)         A person shall submit a sampling plan for Agency approval,

based upon a site-specific evaluation;

2)         For volatile chemicals, compositing of samples is not allowed;

3)         All samples shall be collected within the contaminated area;

4)         Composite samples may not be averaged.  Procedures specified

in "Calculating Upper Confidence Limits for Exposure Point Concentrations

at Hazardous Waste Sites", USEPA Office of Emergency and Remedial

Response, OSWER 9285.6-10 (December 2002), as incorporated by reference in

Section 742.210, or an alternative procedure approved by the Agency, shall be

used to determine sample averages.

e)         When averaging under this Section, if no more than 15% of

sample results are reported as "non-detect", "no contamination",

"below detection limits", or similar terms, such results shall be

included in the averaging calculations as one-half the reported analytical

detection limit for the contaminant.  However, when performing a test for

normal or lognormal distribution for the purpose of calculating a 95% Upper

Confidence Limit of the mean for a contaminant, a person may substitute for

each non-detect value a randomly generated value between, but not including,

zero and the reported analytical detection limit

lations as one-half the reported analytical

detection limit for the contaminant.  However, when performing a test for

normal or lognormal distribution for the purpose of calculating a 95% Upper

Confidence Limit of the mean for a contaminant, a person may substitute for

each non-detect value a randomly generated value between, but not including,

zero and the reported analytical detection limit.  If more than 15% of sample

results are "non-detect", procedures specified in "Guidance for

Data Quality Assessment, Practical Methods for Data Analysis, EPA QA/G-9, QA00

Update", EPA/600/R-96/084 (July 2000), as incorporated by reference in

Section 742.210, or an alternative procedure approved by the Agency shall be

used to address the non-detect values, or another statistically valid procedure

approved by the Agency may be used to determine an average.

f)         All soil samples collected after August 15, 2001 shall be reported

on a dry weight basis for the purpose of demonstrating compliance, with the

exception of the TCLP and SPLP and the property pH.