February 2016 Newsletter

Review of FY 2015 NOAFs Involving Nature and Extent Issues  
By: Wesley E. Stimpson, LSP, Loss Prevention Committee

Note:  After this article was written, the LSPA’s Loss Prevention Committee learned that, through no fault of anyone, it had not received all the NOAFs issued by MassDEP during FY 15.  The total numbers of NOAFs cited in the second paragraph of this article are a subset of all FY 15 NOAFs involving nature and extent issues.  

The LSPA’s annual review of Notice of Audit Findings (NOAFs) is underway.  This article addresses the lessons learned from the MassDEP FY 2015 audit findings that resulted in Notices of Noncompliance (NON) involving primarily the identification of the nature and extent of the OHM (Oil and Hazardous Materials) released into the environment.

MassDEP provided the LSPA Loss Prevention Committee with 241 unique NOAFs.  Approximately 81 NOAFs contained Notices of Violation and 78 of these resulted in MassDEP issuing an NON.  The NOAFs were searched for various keywords.  Of the 78 audits containing NONs, 9 were determined to be appropriate for the key word category “Nature and Extent.”  Five NOAFs were from the Western Regional Office, three were from the Central Regional Office, one was from the Northeast Regional Office and none were received from the Southeast Regional Office.  This population included six RAOs and three Phase II/III reports.  Contaminants of concern ranged from gasoline to manufactured gas plant (MGP) wastes.

The concerns expressed by MassDEP in the NOAFs can generally be organized as follows, listed in order of frequency (Note:  some NOAFs have issues in multiple categories):

Failure to determine horizontal extent (four NOAFs)

  • Lack of data to assess risks was cited at two sites where residential settings were nearby and indoor air contamination could exist. 
  • A Phase II report was connected to a release for which a Downgradient Property Status (DPS) was filed, after the Phase II report was submitted.  The PRP was asked to expand the Phase II work to include the DPS information.  Insufficient data were provided in the upland and wetland areas of the site to support the disposal site boundary indicated in a Phase II report for an MGP site.

 Failure to determine vertical extent (three NOAFs)

  • The vertical extent of soil contamination was not determined at the site of a fuel oil release. 
  • The extent of the impact of a chlorinated volatile organic compound (CVOC) release to groundwater and the extent of nonaqueous phase liquid (NAPL) were not determined.
  • The extent of dense nonaqueous phase liquid at an MGP site was not determined.

Failure to use all data (three NOAFs)

  • An elevated concentration of lead in a soil sample was removed from the data set without justification as to why it might be attributed to a lab error.  The PRP was informed that either the sample should be included in the determination of the exposure point concentration or more sampling should be undertaken to determine representativeness. 
  • Downgradient groundwater quality data were not included within the limits of the disposal site for a gasoline release without any justification for the exclusion. 
  • An RAO removed arsenic and chromium from the evaluation of risk indicating that although it could have come from recent manufacturing activities there was no information to confirm its use.  The RAO therefore attributed the elevated concentrations of arsenic to local geologic conditions.  However, the disposal site had a history of once being used as a leather tannery in the late 1880s, where arsenic was often used in the tanning process.  The RAO did not acknowledge this or justify why the arsenic was not from this source.

Insufficient data to access vapor pathway (three NOAFs)

  • A single set of indoor air data obtained for an unoccupied, unheated space included in a Phase II and III evaluation was determined to be inadequate to evaluate risk from CVOCs. 
  • The potential for an indoor air impact at a multi-family residence at a PCE disposal site boundary was not evaluated even though the available soil gas data indicated an impact was possible. 
  • Despite the history of odor complaints at a condominium building adjacent to an RAO filed for a fuel oil release, no characterization of potential indoor air impacts was undertaken.  The PRP was told to withdraw the RAO.

Failure to identify OHM source (two NOAFs)

  • A former loading dock was determined to be the source of CVOCs in groundwater; however, the dock was cross-gradient to groundwater flow and the PRP was informed that additional up-gradient characterization was needed. 
  • The PRP for an MGP site was informed that additional characterization was needed to determine if underground piping and buried holder and facility foundations might contain waste materials that could be sources of future NAPL releases and soil and groundwater contamination.

Insufficient temporal data (two NOAFs)

  • One data set was determined to be insufficient to determine seasonal trends at a fuel oil release site. 
  • MassDEP concluded that one sampling event was insufficient to provide groundwater and indoor air data to evaluate the impacts from a CVOC release.

Failure to evaluate preferred pathway (two NOAFs)

  • A storm drain present at the site of a fuel oil release was not evaluated as a possible preferred pathway for contamination movement. 
  • Underground piping at an MGP site was not evaluated as a possible preferred pathway.

Failure to test for suspect OHM (one NOAF)

·     A property formerly used as to manufacture plastic toys had evidence of sloppy housekeeping practices, with plastic process wastes found in the floor drainage system.  The PRP was informed that the investigation should have included either soil or groundwater testing for phthalates, a common component of plastics, or technical justification as to why phthalate testing was not necessary. 

Insufficient data set (one NOAF)

·       The PRP for a former MGP site was told that due to the highly variable subsurface conditions at the site, the distribution and frequency of the available data in the submitted Phase II was inadequate and substantially more characterization work was needed.

Included in the NOAFs were two sites where MassDEP referenced Interim Final Guidance as its basis for concluding that more characterization work was needed.  At one site, because the concentration of PCE in a soil gas sample collected in a public way near a multi-family dwelling exceeded the residential sub-slab screening concentration contained in the current VI Guidance [Based on the dates of the submittals and audits, this guidance is assumed to be MassDEP’s 2011 Interim Final Vapor Intrusion Guidance” WSC#-11-435], MassDEP stated that additional assessment of the dwelling was necessary and required the PRP to withdraw the RAO.  In the second case, the PRP was informed that additional Phase II and III work was needed because the indoor air data set used in the evaluation was obtained only once and at a time of the year that did not adhere to the current VI Guidance.

The review of findings from this set of NOAFs reinforces the messages often communicated by the Loss Prevention Committee:

  • Look at your Conceptual Site Model and your data set and evaluate whether it supports your conclusions regarding the source of the contamination. 
  • Put the disposal site boundary on a map and make sure there are sufficient data to describe the boundary. 
  • Confirm that the data set demonstrates stable or decreasing contaminant concentrations. 
  • Look at all of the possible receptors and make sure you have the data needed to evaluate whether there is a significant risk at these locations. 
  • Be aware of the various guidance documents available for your specific contamination situation. 
  • If you are deviating from the recommendations provided in the Final or Interim Final guidance, provide your technical justification clearly and concisely.