|Grundy County, Illinois|
Grundy County Courthouse
Location in the U.S. state of Illinois
Illinois's location in the U.S.
|Founded||February 17, 1841|
|Named for||Felix Grundy|
|• Total||430 sq mi (1,114 km2)|
|• Land||418 sq mi (1,083 km2)|
|• Water||12 sq mi (31 km2), 2.9%|
|• ( 2010)||50,063|
|• Density||120/sq mi (50/km2)|
|Time zone||Central: UTC−6/ −5|
Illinois's state fossil, the unique and bizarre Tully Monster, was first found in Mazon Creek. Grundy County Speedway is located in Morris. Grundy County is also home to Dresden Generating Station—the first privately financed nuclear power plant built in the United States—and the Morris Operation—the only de facto high-level radioactive waste storage site in the United States.
Grundy County was established on February 17, 1841. It was formed out of LaSalle County and named after U.S. Attorney General Felix Grundy (1777-1840).  The county was well known for its coal mines  and attracted miners from Pennsylvania and other regions to work its deposits. The Diamond Mine Disaster occurred in Grundy County. The disaster took the lives of 68 men and boys who were trapped underground when water broke through into the mine after days of heavy rain and the pumps could not keep up with the rising water. 22 bodies were eventually recovered, the remaining 44 were left in the mine and the mine was sealed. Today a marker stands where they felt the majority of the bodies probably ended up. 
|Climate chart ( explanation)|
In recent years, average temperatures in the county seat of Morris have ranged from a low of 13 °F (−11 °C) in January to a high of 85 °F (29 °C) in July, although a record low of −24 °F (−31 °C) was recorded in January 1985 and a record high of 103 °F (39 °C) was recorded in June 1988. Average monthly precipitation ranged from 1.59 inches (40 mm) in February to 4.16 inches (106 mm) in June. 
|U.S. Decennial Census
1790-1960  1900-1990 
1990-2000  2010-2013 
As of the 2010 United States Census, there were 50,063 people, 18,546 households, and 13,431 families residing in the county.  The population density was 119.8 inhabitants per square mile (46.3/km2). There were 19,996 housing units at an average density of 47.8 per square mile (18.5/km2).  The racial makeup of the county was 93.7% white, 1.2% black or African American, 0.7% Asian, 0.2% American Indian, 2.7% from other races, and 1.5% from two or more races. Those of Hispanic or Latino origin made up 8.2% of the population.  In terms of ancestry, 28.3% were German, 23.0% were Irish, 12.7% were Italian, 9.4% were Polish, 8.6% were English, 7.1% were Norwegian, and 3.0% were American. 
Of the 18,546 households, 38.6% had children under the age of 18 living with them, 57.8% were married couples living together, 9.7% had a female householder with no husband present, 27.6% were non-families, and 22.5% of all households were made up of individuals. The average household size was 2.69 and the average family size was 3.16. The median age was 36.1 years. 
The median income for a household in the county was $64,297 and the median income for a family was $75,000. Males had a median income of $58,491 versus $36,592 for females. The per capita income for the county was $27,895. About 5.2% of families and 6.9% of the population were below the poverty line, including 8.0% of those under age 18 and 6.5% of those age 65 or over. 
Grundy County is divided into seventeen townships:
As part of Yankee rural Northern Illinois, Grundy County has generally been powerfully Republican, although it did support Progressive Theodore Roosevelt in 1912 when the Republican Party was mortally divided. Only one Democratic presidential candidate has ever won an absolute majority of Grundy County’s vote – Franklin D. Roosevelt in 1932 – although in recent times the county has trended a little more Democratic and both Bill Clinton in 1996 and Barack Obama in 2008 won pluralities. However, in 2016 with economic concerns in the “ Rust Belt”, Donald Trump did better than any Republican in this traditional GOP county since 1984, when Ronald Reagan came within 3,819 votes of clean-sweeping all fifty states.
In September 2017, Governor Bruce Rauner said he would sign a controversial abortion funding expansion measure, House Bill 40, into law. Critics said that the law will increase the number of abortions from the reported 64 in Grundy County in 2015. Illinois Right to Life estimated that the new law will lead to 12,000 additional abortions each year in Illinois at a cost of more than $21 million. The estimate was based on Medicaid figures from the late 1970s, which was the last time Illinois had unrestricted Medicaid funded abortions. 
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- "Critics say HB 40 likely to increase number of abortions over 64 on record for Grundy County in 2015". Grundy Reporter. 2017-09-28. Retrieved 2018-04-09.
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