Remediation News June
1999 (Vol 11 N0 1) Article
Revisions to the Soil Cleanup Criteria
By: Barry Frasco,
Hazardous Site Science Element
Soil Cleanup Criteria (SCC) were first published in the
April 1993 issue of the Site Remediation News (Volume 5,
Number 1). The SCC were revised in April 1994 (Site Remediation
News, Volume 6, Number 1) and a revised lead criterion was
added in 1995 (Site Remediation News, Volume 7, Number 1).
These criteria have been provided to the regulated community
as an interim guide in assessing contaminated/potentially
contaminated sites pending Department promulgation of soil
remediation/cleanup standards. The Department’s Site Remediation
Program is currently in the process of developing soil remediation
standards in accordance with the Brownfield and Contaminated
Site Remediation Act, N.J.S.A. 58:10B-12. The Department
anticipates that a Draft Rule Framework will be prepared
for Interested Party Review and Comment by the fall of 1999.
As such, the Department has determined not to make large-scale
revisions to the SCC prior to the Interested Party Review.
However, the Department, based on the reasons noted below,
is making four (4) revisions to the SCC, which are effective
immediately. These revisions are:
Addition of soil cleanup criteria for trivalent
and hexavalent chromium – Soil cleanup criteria
for trivalent and hexavalent chromium were announced
by the Department in September 1998. While these criteria
have been in existence for over six months and are available
on the Site Remediation Program Web Site (www.nj.gov/dep/srp/regs/guidance.htm),
they had not been incorporated into the main SCC document.
Increase in the xylene soil Impact to Ground Water
criterion – The change in the Department’s Drinking
Water Standard for xylene from 44 ug/l to 1000 ug/l
resulted in a change of the soil impact to ground water
to 67 mg/kg. While the Site Remediation Program has
routinely allowed the use of the 67 mg/kg value, it
has been via the Alternate Cleanup Standard (ACS) process.
The Department recognizes that the use of the ASC process
to allow for the use of the new xylene impact to ground
water criterion is an unnecessary administrative activity.
As such, the new xylene impact to ground water criterion
was been incorporated into the SCC document. However,
it should be noted that the Department’s current policy
to use a 10 mg/kg soil xylene concentration as a trigger
for the collection of a ground water sample for BTEX
compounds has not changed.
Increase in the Residential Direct Contact SCC for
cadmium – Using the USEPA equation for ingestion
of noncarcinogenic contaminants, USEPA default parameter
inputs and USEPA IRIS toxicity data, a residential direct
contact soil concentration for cadmium of 39 mg/kg is
derived. The Department has routinely allowed this approach
for the development of an ACS for cadmium. As such,
the Department has determined that the use of the ACS
process to develop the 39 mg/kg soil criterion is an
unnecessary administrative activity. Therefore, the
SCC document has been revised to include the new residential
direct contact value for cadmium. However, it should
be noted that the new residential direct contact soil
criterion may not be protective of ground water and
an evaluation of site specific chemical and physical
parameters is required to determine if there is any
potential/actual impact to ground water. Because of
this potential impact to ground water and that there
have been no ACS requests for the Non-Residential land
use scenario, the Non-Residential Direct Contact Soil
Criterion for cadmium will remain at 100 mg/kg.
- Increase in the residential and Non-Residential
Direct Contact SCC for beryllium – The Brownfield
and Contaminated Site Remediation Act, N.J.S.A. 58:10B-12g(4),
states “Remediation shall not be required beyond the regional
natural background levels for any particular contaminant.”
The Site Remediation Program has reviewed numerous soil
background determination submissions for beryllium where
the natural background soil concentration was between
1mg/kg and 2mg/kg. Examination of background sample data
from Fields, et al (1993) reveals that the 95th percentile
value of the distribution of beryllium data is 2 mg/kg.
The Department believes that this value is a reasonable
determination of natural soil background for beryllium
in New Jersey. This conclusion was also made in the Technical
Basis and Background document (1992) that accompanied
the 1992 proposed, but never adopted, soil cleanup standard
regulations, N.J.A.C. 7:26D. In an effort to reduce the
number of background soil determination submissions (which
have been routinely approved), the SCC for beryllium has
been changed to 2 mg/kg to reflect a general background
level for the State of New Jersey.
As noted in the past, notwithstanding where the soil cleanup
criteria are based on human health impacts, the Department
shall still consider environmental impacts when establishing
site specific cleanup criteria. This along with other site-specific
factors including background conditions may result in site
specific cleanup criteria which differ from the criteria
listed in the SCC document. Therefore, the SCC list shall
not be assumed to represent approval by the Department of
any remedial action or to represent the Department’’ opinion
that a site requires remediation.
Included is the newly
revised Soil Cleanup Criteria document. This revised
document is also available for review and downloading on
the Site Remediation Program Web Site, www.nj.gov/dep/srp/regs/scc.
Fields, T., T. McNevin, R. Harkov and J. Hunter. 1993.
A summary of selected soil constituents and contaminants
at background locations in New Jersey. N.J. Department of
Environmental Protection Publication.
NJDEP. 1992. Technical Basis and Background for Cleanup
Standards for Contaminated Sites, N.J.A.C. 7:26D. USEPA
1996. Soil Screening Guidance: User’s Guide. EPA/540/R-96/018.
USEPA 1998. The Integrated Risk Information System (IRIS).