Statement_of_Work_(draft)_1.pdf

STATEMENT OF WORK (draft)

I. GENERAL INFORMATION

A. Introduction (general description of services).

Selenium is a naturally occurring element that can be mobilized by farming irrigation practices, leading to high concentrations in drainage waters. Selenium toxicity has significant impacts on the hatching of eggs and development of early life stages in oviparous animals, and reproductive consequences of maternal transfer are the among the most direct and sensitive predictors of the effects of Se (Heinz 1996; Janz and others, 2010). Factors controlling selenium uptake at the base of the food web as well as assimilation efficiency and retention in consumers, are both species-and environment-specific. Furthermore, as the Salton Sea recedes, agricultural drain water flow onto the exposed lakebed creating playa wetlands that are unmanaged for Selenium risk to wildlife. In their synthesis of selenium research and monitoring at the Salton Sea, Rosen et al.

(2023), identified several data gaps that prevent us from fully identifying Se hazards to fish and wildlife. In particular, lack of information on water source and resulting Selenium load, habitat-specific biogeochemistry, Se bioavailability and transfer up trophic levels, and species habitat use precludes ecosystem-scale modeling (e.g. Presser and Luoma 2010, Rosen et al., 2023).

USGS Western Ecological Research Center is conducting research to address these uncertainties working with existing research partners in a phased approach. Initial pilot samples (water, sediment, and vegetation) have been processed for total Selenium within wetlands that were occupied by the endangered Yuma rail (Rallus longirostris yumanensis). These wetlands were sustained by different water sources such as agricultural drains that are expected to have higher Selenium loads and the Colorado River which has low Selenium concentrations.

Here we propose to analyze our pilot samples for total Selenium to help assess Selenium risk to Yuma rails. Sample types include: particulate organic matter on filters, detritus, algae, cattail, invertebrates and fish tissues. We request using the same external laboratory that we have used for the pilot Selenium concentrations for data consistency. We anticipate seeking additional funds for future project phases which would include analyses of other trace elements that could impair Yuma rail health and reproduction; however, these funds have not yet been obtained.

II. WORK REQUIREMENTS

A. Technical Requirements.

All samples will be collected using standard protocols. Sample types include: particulate organic matter on filters, detritus, algae, vegetation invertebrates and fish tissues. Samples will be packed in dry ice and shipped following appropriate Chain-of-Custody procedures that documents the location and possession of the samples at all times, and identify the laboratory analyses requested for each sample.

Vendor will need to follow standard method testing procedures or other procedures provided by the Environmental Protection Agency (EPA) and US Fish and Wildlife guidelines for at least a 0.5 micrograms/liter detection limit for Selenium in biological tissues and sediment.

In addition, the laboratory must provide the following services:

Sample QA/QC should include (a method blank, spiked blank, certified reference material, duplicate sample, and spiked sample for each group of 20 or fewer samples

Dry and grind dried sediment samples for analysis when applicable.

Percent moisture for each biological tissue sample

Deliverables:

Results must be delivered to Point of Contact electronically as a .csv or excel file within 90 days of sample submission, or at a later date agreed upon by the USGS POC.

Data will be reviewed by the USGS POC within 60 days of receipt of the data. Remaining sample material may be used by a separate laboratory for isotope analyses. Please notify the USGS POC of any remaining sample material. Remaining sample material may be disposed of only after USG POC confirms they are not needed for other analyses and after data review shows no further analyses are needed.

Other The contractor must have the appropriate laboratory space, equipment, and personnel, and expertise to complete and deliver the laboratory analyses. No Government Property will be furnished or provided for this agreement.