# EPA Objectives for Siloxane 

# Environmental Monitoring

December 6, 2012 Cathy Fehrenbacher

# EPA Objectives for Siloxane Environmental

Monitoring (communicated in writing December 20, 2010 and September 19, 2011, in informal pre

- ECA process meetings, and during ECA process)
D 4 / D 5 Environmental Monitoring The monitoring program is intended to develop a better understanding of the sources of and pathways to the environmental concentrations of D 4 /D 5 in environmental media and biota associated with industrial releases from manufacturing, processing, formulation (MPF) and high

volume industrial or commercial end users of D 4 /D 5 . The program also intends to include the full product life cycle from manufacturing through processing, formulation, high volume industrial or commercial end use and disposal as described in the bullets below. The proposed essential elements of the monitoring program include: Representative Municipal & On

- site Industrial Wastewater Treatment Plant ( WWTP) Monitoring

– Influent concentrations and flowrates

– Effluent concentrations and flowrates

– Biosolids and their potential migration from land application to water bodies

– Site selection should encompass a representative range of on

- site handling and treatment practices , for wastes, discharge waters, nearby population centers, and low and high flow.

– Sampling of locations should include points upstream and downstream (progressively distant from point of discharge)

– Examination of surface water , suspended solids, bottom sediments, air, biosolids and benthic and aquatic organisms• Monitoring program should include the full product life cycle from manufacturing

through processing, formulation, end use, and disposal

• Representative watersheds and industrial manufacturing, processing and formulating sites

• A representative number of sites would be selected based on information obtained from the development of Conceptual Site Models which characterize sources and releases for all manufacture, processor, formulator facilities

• The treatment configurations of WWTP must be considered (activated sludge vs lagoon etc.)

• The population of area that is connected to the facility must be a consideration in the selection of sites for both municipal WWTP sites and MPF sites. Geologic, geographic, and climatic parameters must also be considered.

• Characteristics of the receiving water body must also be considered.

• Care also needs to be taken in selecting which POTW will be chosen for a given metropolitan area as a large municipality may have facilities of varying sizes. 

# EPA Objectives

- Monitoring Site Selection

## • Biota monitoring must support the evaluation of bioaccumulation and biomagnification in biota including at 

## least 3 replicate samples of specific species per site, with fish species selected to represent at least two trophic levels/levels of aquatic food web (low and high), and 

## additional benthic species, and environmental occurrence sampling. 

# EPA Objectives

- Biota Monitoring

# EPA Objectives

- Existing Monitoring

Data

• EPA will consider existing monitoring data collected at sites inside and 

### outside the US provided they are shown to have similar and representative site characteristics. These characteristics include: watershed; air

- shed; facility production and releases of D4/D5; run

- on and run

- off potential ; waste generation, handling and disposal for on



### site waste water treatment facilities; on

- site waste disposal units such as waste piles, dumps, ponds, pits, landfills, ditches or land applied sludge areas; site climate, hydrology, geology, soil type; receiving stream morphology, sediments, flow rate, nutrient load, water chemistry, 

### aquatic biota on and around the chosen manufacturing facilities.

• Submission of existing monitoring data is encouraged to further enhance the understanding of the behavior of D4/D5 in the environment although the EPA will have a high bar for substitution of foreign data for 

### monitoring at US sites based on representativeness.

# Modifications to EPA Siloxane 

# Monitoring Objectives During ECA

Negotiation

• Intended to focus the monitoring for risk assessment purposes

– Fewer MPF monitoring sites

– Fewer POTW monitoring sites



# – Deletion of air monitoring

– Deletion of downstream monitoring

– Biota monitoring has been limited to industrial sites