Two environmental groups recently filed separate lawsuits against the EPA hoping for further action in addressing nutrient loadings in our nation's waterways. The groups cited water quality problems in our nation's waterways related to excessive algae growth and other nutrient loading issues.
One of the groups concerned with the water quality in the Gulf of Mexico, wanted numeric limitations for nitrogen and phosphorus when such standards aren't already set by each state's water quality standards. Nitrogen is a limiting nutrient in salt water bodies whereas phosphorus is a limiting nutrient in fresh water bodies. The group wants either minimum numeric criteria set or for the EPA to issue a Total Maximum Daily Load for these nutrients.
The EPA denied the group's initial petition, stating it wanted to support targeted regional and state activities and help with the development of state approaches to controlling these nutrients.
Algae Blooms in a fresh water pond
The second lawsuit, by an environmental organization based in New York, wanted action from the EPA on a petition it filed with the EPA in 2007. The petition asked for the EPA to publish revised information regarding the technology for municipal wastewater treatments plants, particularly to reflect recent improvements in nutrient removal in some processes. The publication regarding these treatment plants was last updated in 1985. The group claims updating the publications would form the basis for regulating wastewater treatment plants in the future, requiring some minimum level of nutrient removal.
If you have any questions about wastewater treatment processes or nutrient removal from wastewater, please contact Kevin Klein, P.E. at (508) 747-7900 extension 130.
Information in this blog post taken from the May 2012 issue of Civil Engineering Magazine, article entitled "Lawsuits Seek to Compel US EPA to target Nutrients more Aggressively" by Jay Landers, Pg 22-25.
We read a very interesting article recently in the April 2012 edition of Civil Engineering. The article by Jay Landers discusses a pilot study being done in San Lius Obispo's Water Reclamation facility. The study is designed to test using solar energy and photosynthetic algae to treat wastewater, and then possibly using the algae to generate biofuel. The goal is to develop an inexpensive method of treatment that will reduce nutrient levels and have a valuable byproduct (fertilizer, biofuels). This treatment process could result in a more sustainable and cost effective approach when compared with conventional manners.
As part of the project, the facility uses raceway style algae ponds. The raceway style ponds produce algae at a much higher rate than conventional ponds, and can accelerate photosythetic oxygen production and nutrient assimilation by the algal cells. Algae uses significantly les energy and lower volumes of chemicals than conventional approaches do, as it relies mainly on solar power. It is a more sustainable process, using much less energy than an activated sludge process.
One problem facing the systems is that solar energy requires a large amount of flat land, which may not always be available near a wastewater treatment plant facility.
If the pilot study is successful, the algae will be generated efficiently, and the removed without coagulants, hopefully by settling out to allow for harvesting. The harvested algae can be dewatered for use as fertilizer or biofuel production.
This pilot study is set to run through April 2013. We'll be very interested to see how the study works out. If you have questions about wastewater treatment processes or innovative approaches to wastewater treatment, please contact Kevin P. Klein, P.E. at (508) 747-7900 extension 130.
Information for this blog post taken from article entitled "Pilot Plant Used to Evaluation Algae for Wastewater Treatment and Biofuel Production" p40-41, Civil Engineering, April 2012, by Jay Landers.
High levels of nutrients and sediment have been plaguing the Chesapeake Bay for several years, leading to many problems. Some measures have been taken and efforts have been made to try to lower pollutant loadings to the Bay, but they have not been very successful and these efforts were partially cancelled by the population boom and a rapid development in the Bay. The Total Maximum Daily Load (TMDL) for the Chesapeake Bay and its tributaries was finalized by the USA EPA on December 29, 2010 and came out in April 2011 with the aim of ambitiously reducing nutrients, sediment and total suspended solids (TSS) entering the waterways. The TMDL is seen as a positive step to improve the condition of the Bay.
The reduction will be achieved in different steps:
- Point and non point sources will reduce pollutant loadings in the next several years
- Implementation measures will be instituted by 2025
- A series of intermediate deadlines to ensure continual progress in the implementation of the TMDL in the next 15 years will be imposed. The ‘’milestones’’, for example, are part of these deadlines. Jurisdictions will start the milestones in 2012.
The TMDL sets also ambitious goals for WWTPs within the Bay’s watershed. Many wonder how the TMDL can impose pollution reductions from non point sources that are not addressed by existing regulatory programs related to clean water. Aggressive efforts have already been made over the years to reduce nutrient discharges from WWTPs and it led to significant decreases in pollutant loadings from non point sources and agriculture. The TMDL requires even better results. Large WWTPs are required to decrease discharges of nitrogen by 27% and phosphorus by 26% from 2009 levels. Agriculture must cut its loadings of nitrogen by 38% and phosphorus by 31%.
HISTORY AND CONSEQUENCES
Over the years, different agreements have been reached to reduce pollutant loads and this effort provided good results. However, it has not been enough because of the presence of nutrients and sediment, water quality and water clarity have consequently decreased since the 1970s. Excessive algal growth and low concentrations of dissolved oxygens are part of the chronic problems of the Bay as well.
MAJOR CUTS EXPECTED BY THE TMDL
- Total nitrogen : a reduction of 25 % compared to the 2009 level
- Total phosphorus : 24% less than in 2009
- TSS : a decrease of 20% compared to 2009
The pollution limits are designed to ensure compliance with state water quality standards.
PROCESS TO ELABORATE THE TMDL
The six states within the Chesapeake Bay watershed: Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia, and the District of Columbia, worked together to help develop the TMDL. They prepared a Phase I Watershed Implementation Plan (WIP), which gives the outlines to each jurisdiction to meet its allocated pollutant loads. Then, each jurisdiction has until early 2012 to develop its Phase 2 WIPs. The WIPs will include additional detail about nitrogen, phosphorus, and sediment controls at the local level.
The role of EPA is to ensure pollution reductions and to ensure that the jurisdictions enforce the measures. If a plan is inadequate or the progress is insufficient, the EPA may take the appropriate contingency actions and require additional reductions pollution reductions from non point sources such as WWTP. Point sources have achieved enormous reductions of nutrients in the bay, but it would be too expensive and unproductive to rely ultimately on further reductions from WWTPs.
The TMDL is a promising step in the field of pollutants reductions. However, issues like funding, legal and legislative challenges could delay or affect its implementation.
If you have any questions about pollutants, non point sources or WWTPs, please contact John McAllister at email@example.com or at (508) 747 - 7900 x 117.
Information in this article taken from April 2011, article ‘Chesapeake Bay TMDL calls for steep cuts in nutrient, sediment loads‘’ by Jay Landers, published in WE&T.