This report will enable the Minnesota Pollution Control Agency (MPCA) to provide recommendations to the Corps of Engineers regarding a search of the available regulatory, historical, and geological sources of information. The findings, conclusions, and engineering considerations contained within this report will form the foundation for optimizing future field investigation strategies for determining the existence of environmental hazards. This report summarizes the environmental investigation findings based on historical, geological, and regulatory agency records for Stages 3 and 4 of the Chaska Flood Control Project. The investigation was conducted to minimize the possibility that unexpected hazardous, toxic, or otherwise regulated materials and/or contaminants will be encountered during construction phases of the Chaska Flood Control Project. This study will enable the project designers to anticipate requirements for special handling of materials and groundwater during construction and to make alignment changes to minimize the need for special handling. The proposed flood control project is located in east central Minnesota, on the southern and eastern edges of the City of Chaska, in Carver County. Chaska is located approximately thirty miles southwest of St. Paul. Stage 3 of the flood control project consists primarily of a diversion channel which will protect Chaska from flooding in East Creek during a 5,500 cfs flow event. The diversion originates near Highway 17 and Engler Boulevard with a 3400 foot twin levee riprapped lined channel which merges into a 1,300 foot grass lined channel. Stage 4 of the flood control project consists of 2,800 feet of new levee and an elaborate system of relief wells and interceptor pipes on the landward side of the levee, as well as the use of wick drains and a staged construction of the levee to consolidate and strengthen the foundation soils under the new levee prism.

This Phase II Investigation Work Plan discusses the field work and laboratory testing required to determine the extent of contaminated materials to be encountered during the construction of Stage 4 of the Chaska Flood Control Project. This work plan was developed in response to indications of potentially contaminated soils and groundwater (petroleum products, petroleum product and solvent odors, and dump/debris fill) encountered in several geotechnical soil borings advanced for geotechnical design purposes along the proposed levee and channel alignments. These borings were advanced for physical property testing rather than for contaminant analysis since contaminated materials and/or groundwater were not anticipated on these stages of the project. In addition, potential contamination sources were identified during a Phase I Environmental Site Assessment for these stages of the project. According to the Minnesota Pollution Control Agency (MPCA) document "Update on Property Transfer Cleanup Assistance", a Phase II Investigation Work Plan is required to determine if the potential sources of contamination identified during the Phase I Investigation are actually causing a release or threatened release of hazardous substances to the soil and groundwater at the project site. This work plan contains background information on the site; the scope of work for Task 1, Work Plan and Health/Safety Plan, Task 2, Field Investigation Work, and Task 3, Phase II Investigation Report. The report also describes the methodology that should be followed in conducting soil borings, hand auger borings, soil classification, soil sampling and chemical analysis, decontamination, soil headspace analysis, and chain of custody.

This is a print on demand edition of a hard to find publication. Report of a survey conducted by the EPA and its state and tribal partners of the nation's lakes, ponds and reservoirs. This National Lakes Assessment is designed to provide statistically valid regional and national estimates of the condition of lakes. It uses a probability-based sampling design to represent the condition of all lakes in similar regions sharing similar ecological characteristics. Consistent sampling and analytical procedures ensure that the results can be compared across the country. The National Lakes Assessment helps build state and tribal capacity for monitoring and assessment and promotes collaboration across jurisdictional boundaries in the assessment of water quality. Charts and tables.

In September 1989, dogs and sheep died at Rutland Water following the ingestion of a scum of toxic blue-green algae. The NRA therefore undertook the first major national appraisal of blue-green algae throughout England and Wales. Their report describes the results of the 1989 survey and looks at how events were managed. Recommendations are made for future management, monitoring, research and development. It also reviews blue-green algal toxins, the factors which affect blue-green algal bloom production and approaches to controlling algal populations.