Groundwater Health Limits For Trimethylbenzene

The Health Risk Assessment Unit at the Minnesota Department of Health has started a full review of three trimethylbenzene (TMB) isomers (1,2,3-trimethylbenzene; 1,2,4-trimethylbenzene; and 1,3,5-trimethylbenzene). TMB isomers are produced during petroleum refining and production of a component of gasoline. TMB isomers are also used in the production of solvents and are ingredients in paints, dyes, cleaning agents, and automotive fluids.

 The review will consider if the existing Health Risk Values (HRL) for the three trimethylbenzene compounds in groundwater are adequately protective. This review is particularly significant because trimethylbenzene compounds are commonly detected in soil and groundwater at petroleum release sites, such as leaking underground storage tank (LUST) sites.

 MDH previously developed water guidance for 1,2,4- and 1,3,5-trimethylbenzene. Re-evaluation of these contaminants in 2017 resulted in a recommendation for full review.



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Waters of the United States Definition Addressed By Supreme Court

On January 22, 2018, the Supreme Court unanimously decided a procedural issue determining the court in which challenges to the meaning of the term “Waters of the United States” (WOTUS) may be brought. The choice of court is significant because it affects the resources needed to litigate the merits of challenges, sets the statute of limitations for filing lawsuits and helps determine whether actions can be challenged in subsequent civil or criminal proceedings.

Immediate Impact of Waters of US Decision

The decision requires that any challenge to the current meaning of WOTUS must be brought in the federal district court rather than in the federal court of appeals and allowed pending litigation in the district courts to continue. Lifting the stay puts the Obama-era WOTUS definition back into effect and forces any future litigation to occur throughout the United States wherever there is a challenge to the WOTUS definition, unless it is able to get a stay in the pending litigation.

Why is Waters of the US Definition Important?

WOTUS is a key term impacting the scope of Clean Water Act. The EPA and Corps of Engineers issued the definition in May 2015. The rule was widely criticized, with many, such as farmers, home builders, and developers, claiming that the rule impermissibly allowed EPA to regulate private land. Others felt the rule narrowed federal jurisdiction. In the Supreme Court, the current Administration argued that any challenges to the meaning of WOTUS must be brought in a court of appeals; this argument was rejected in the court decision. Under the Clean Water Act, the uncertainty as to the scope of the WOTUS rule affects whether a Federal discharge permit (NPDES permit) is required and the scope of permits needed to discharge wastewater and storm water. It also impacts whether real estate contains federally-regulated wetlands.

Changes To Minnesota Water Based Health Risk Limits

The Minnesota Department (MDH) is proposing amendments to the Health Risk Limits (HRLs) Rules and to adopt new and updated human health-based water guidance values into rule. The chemicals proposed for amendment include herbicides and other pesticides, polyaromatic hydrocarbons (PAH) and volatile organic compounds (VOC). Below is a listing of chemicals MDH is considering in its rule revision:

Chemical Name	Previously adopted values in HRL Rule?
Acenaphthene	Yes
Acetochlor	Yes
Acetochlor ESA	Yes
Acetochlor OXA	Yes
Alachlor	Yes
Chloroform	Yes
Clothianidin	No
Cyanazine	Yes
cis-1,2-Dichloroethene	Yes
2,4-Dichlorophenoxyacetic acid (2,4-D)	Yes
Dieldrin	Yes
Dinoseb	No
S-Ethyl-N,N-dipropylthiocarbamate (EPTC)	Yes
Fluoranthene	Yes
Perfluorobutyrate (PFBA)	Yes
Perfluorooctanoic Acid (PFOA) and Salts	Yes
Perfluorooctane Sulfonate (PFOS) and Salts	Yes
Pyrene	Yes
Tetrahydrofuran	No
Thiamethoxam	No
1,1,1-Trichloroethane	Yes
Vinyl Chloride	Yes

MDH will accept written comments on the proposed rules amendments through Wednesday, February 21, 2018.

Benzo[a]pyrene, BaP Water Health Risk Review

The Minnesota Department of Health-Health Risk Assessment Unit has started a full review of benzo[a]pyrene or BaP. BaP is a chemical formed from combustion, and is one of a larger class of chemicals known as polycyclic aromatic hydrocarbons (PAHs). Sources of BaP can include industrial processes, cigarette smoke, grilled or broiled foods, wood fires, motor vehicle emission, and many other activities that involve combustion of organic material. BaP is classified as carcinogenic to humans by the U.S. Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC). Minnesota Department of Health previously developed water guidance for BaP in 2012 and the current review will update that guidance if deemed necessary.

Revisions To Narrative Water Quality Standards Proposed By EPD

The Georgia Environmental Protection Division has proposed revisions to existing rules in the Rules for Water Quality Control at 391-3-6-.03(5)(b) and (c). These proposed changes are intended to clarify certain narrative water quality standards that could apply to all Waters of the State.

The current rules state, in relevant part:
 (b) All waters shall be free from oil, scum and floating debris associated with municipal or domestic sewage, industrial waste or other discharges in amounts sufficient to be unsightly or to interfere with legitimate water uses.
(c) All waters shall be free from material related to municipal, industrial or other discharges which produce turbidity, color, odor or other objectionable conditions which interfere with legitimate water uses.

The proposed revisions would modify these sections (as noted in red) as follows:
 (b) All waters shall be free from oil, scum and floating debris associated with municipal or domestic sewage, industrial waste or other discharges in amounts sufficient to be unsightly or to unreasonably interfere with the designated use of the water body.
(c) All waters shall be free from material related to municipal, industrial or other discharges which produce turbidity, color, odor or other objectionable conditions which unreasonably interfere with the designated use of the water body.

 Comments on the proposed revision are due by January 31, 2018.

  Click here for other regulatory updates for Georgia.

Ohio Proposes Changes To Permit To Install Rule

Ohio EPA has proposed rule changes in Ohio Administrative Code (OAC) Chapter 3745-42. Chapter 3745-42 covers the requirements for wastewater permits to install (PTIs).The rules are being amended as part of the five-year rule review requirements in Ohio Revised Code section 106.


The Agency has reviewed these rules and has identified necessary changes. New exemptions are being considered, with qualifiers, for:
•building sewers, sanitary sewer replacement projects, in situ sanitary sewer repairs,
•repair or replacement of a treatment works component, media or equipment, modifications within existing treatment works infrastructure,
•disposal systems designed to be a best management practice under a storm water National Pollutant Discharge Elimination System (NPDES) permit,
•treatment works pilot study, •installation of on line monitoring or process control equipment, •installation of odor control equipment,
•remodel or replacement of buildings or laboratories located at a treatment works, and
•filtration systems, ion exchange systems and oil skimmers on process tanks that serve manufacturing equipment.


Click here to review examples of Caltha projects related to permitting. Click here for examples of project Caltha has conducted for clients located in Ohio.

Minnesota Issues Update To Drinking Water Guidance For Glyphosate

The Minnesota Department of Health (MDH) has issued its final health-based guidance on glyphosate. Glyphosate is a widely used herbicide that controls broadleaf weeds, grasses, and aquatic plants. Glyphosate is sold under several different trade names, including products sold for home use. It is applied in agriculture, forestry, lawn care, and gardening.


The Minnesota Department of Agriculture (MDA) regularly monitors groundwater and surface water for glyphosate. It is frequently detected at low levels in both urban and rural surface waters. In 2016, the highest level detected in surface water was 42.8 micrograms per liter (μg/L. MDA’s groundwater monitoring efforts have not yet detected glyphosate in groundwater. Since 1993, glyphosate has only been detected four times in Minnesota public drinking water systems, at levels that range from 1.1 to 39 μg/L


Glyphosate has been under review by MDH. Based on available information, MDH developed a guidance value of 500 ppb for glyphosate in drinking water. Glyphosate is a primary drinking water contaminant of the federal Safe Drinking Water Act and has a Maximum Contaminant Level (MCL) and Maximum Contaminant Level Goal (MCLG) of 700 ppb.