UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

Region 1 

December 2, 2013 

Michael Kuhns 

Director 

5 Post Office Square, Suite 100 

Boston, MA 02109-3912 

Bureau of Land and Water Quality 

Department of Environmental Protect'ion 

17 State House Station 

Augusta, Maine 04333-0017 

Dear Mr. Kuhns: 

I would like to take this opportunity to highlight for you EPA's recent publication of fmal 

ammonia and recreational water quality criteria recommendations, and urge you to 

consider adoption of these criteria into your water quality standards. These recently 

published criteria documents reflect once again the Agency's commitment to improving 

and updating the science bolstering protection of our Nation's water resources. As you 

know, EPA's water quality standards regulations at 40 CFR 13l.ll(a)(l) require states to 

adopt protective criteria that are based on sound scientific rationale. The publication of 

EPA recommendations under Clean Water Act section 304(a) provides an excellent 

opportunity for you and your stakeholders to review existing water quality criteria and 

determine whether those existing criteria are still, in fact, protective and based on sound 

scientific rationale. I encourage you to consider adoption of these or equivalently · 

protective criteria, and to use your triennial public hearings (required by 40 CFR 

131.20(a)) to provide a venue for public feedback on the need to adopt new or modify 

existing WQS to reflect the latest science. 

EPA's CW A section 304(a) criteria recommendations provide scientific 

recommendations to states and authorized tribes in developing new or revised water 

quality standards. States and authorized tribes have the discretion to adopt EPA's criteria 

recommendations; EPA's recommendations modified to reflect site-specific conditions; 

or criteria based on other scientifically defensible methods. 

EPA last issued final ambient water quality criteria recommendations for recreational 

waters in 1986 and for ammonia in 1999. The new water quaRity criteria reflect the 

significant research that has taken place between then and now on these pollutants and 

the levels that are protective of designated uses. 

Recreational Water Quality Criteria 

The recreational water quality criteria were developed based on a review of historic 

studies and more recent scientific information including the National Epidemiological 

and Environmental Assessment of Recreational water studies at U.S. beaches in 2003, 
2004, 2005, 2007, and 2009. Those studies enrolled 54,250 participants, encompassed 

nine locations, and collected and analyzed numerous samples from a combination of 

fresh, marine, tropical, and temperate waters. The resulting criteria have numerous 

improvements over the 1986 criteria: 

• The criteria consist of both a geometric mean and statistical threshold value. 

• The criteria now comprise a magnitude, duration, and frequency. 

• States may choose from two different sets of recommended criteria values to 

protect primary contact recreation waters. 

• The criteria recommendations for fresh and marine waters are based on the same 

illness rate. 

• The criteria no longer refer to different use intensities. . 

• States may take advantage of newly-developed rapid tes~ (qPCR) methods in 

adopting WQS. 

• States may now use Beach Action Values in their beach notification programs. 

As you know, as a BEACH Act state, Maine has specific requirements regarding 

recreational water criteria. Section 303(i)(l)(B) of the Clean Water Act (as amended bY. 

the BEACH Act of 2000) directs each state with coastal recreational waters to adopt and 

submit to EPA new or revised water quality standards for those waters for all pathogens 

and pathogen indicators to which the new or revised water quality criteria are applicable. 

The deadline for state adoption and submittal to EPA of revised WQS is three years from 

EPA publication of new recommendations. Since EPA published fmal recreational water 

quality criteria recommendations in December 2012, states should complete this action 

by December 2015. EPA's 2012 recommendations apply to all waters designated for 

primary contact recreation. 

You can find more information on the 2012 recreational water quality criteria on EPA's 

website, at http://water.epa.gov/scitecb!swguidance/standards/criteria/health/recreation/. 

Ammonia Criteria 

In updating the 1999 ammonia criteria, EPA conducted an extensive literature review that 

incorporates new toxicity data from 69 studies, including new data on freshwater mussels 

and gill-bearing snails, which are both sensitive to ammonia toxicity. In particular, the 

freshwater mussels are more sensitive to ammonia than the organisms included in the 

1999 criteria dataset. You can fmd more information on the 2013 ammonia water quality 

criteria on EPA's website, at 

http://water.epa.gov/scitech/swguidance/standards/criteria!aqlife/arnmonia/. 

Because both these newly published criteria rely on the latest research and science, I 

encourage you, when re-examining your water quality standards during the next triennial 

review, to consider adoption of these criteria into your water quality standards. If, after 

you review your existing water quality standards, you conclude that updates to your 

ammonia and recreational water quality standards are not necessary to protect the 

designated uses, I urge you to submit, in your triennial review, your rationale for not 

making a change. 

I hope these new criteria provide you with the information you need to move forward as 

you consider changes to your water quality standards in the near future. I appreciate your 

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commitment to protecting water quality, and look forward to continuing to work 

collaboratively towards our mutual goals. Ifyou should have any additional questions, 

please feel free to contact me or Ellen Weitzler for more information. 

Sincerely, 

(h/v--

Ken Moraff, Director 

Office of Ecosystem Protection 

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