Question: What California county is Carondelet High School in?

Context paragraphs:
The Academy of Our Lady of Peace: Academy of Our Lady of Peace (locally called "OLP"), is a Catholic high school for young women started by the Sisters of St. Joseph of Carondelet (CSJ).  Located in the Roman Catholic Diocese of San Diego, OLP's mission statement is as follows: "Founded and rooted in the Gospel values of the Catholic church and the charism of the Sisters of St. Joseph of Carondelet, the Academy of Our Lady of Peace empowers young women in an innovative learning environment that honors the individual while fostering community, and develops faith-filled leaders dedicated to the "love of God and the dear neighbor without distinction."  Though the school itself is Catholic, the student body represents a diverse body of religious, racial and social backgrounds, and serves the communities of San Diego County and Tijuana, Mexico.  Its local partner, or 'brother school', is Saint Augustine High School for young men, commonly called "Saints".

Sierra League (Nevada): The Sierra League is one of two leagues in the Northern Nevada 4A Region for high school athletics.  The 4A level is the large school classification, which has schools with enrollments of 1,200 and higher.  The other division is the High Desert League.  The Sierra League consists of seven schools in Nevada and one in California: Carson High School, Churchill County High School, Damonte Ranch High School, Douglas High School, Galena High School, Manogue High School, and Wooster High School.

Anaheim High School: Anaheim High School is a public, four-year high school in the city of Anaheim, California, United States.  Anaheim High School was first established in 1898, which makes it the oldest of nine comprehensive high schools in the Anaheim Union High School District.  It is the third oldest high school in Orange County, behind Santa Ana High School (1889) and Fullerton Union High School (1893) The traditional rivals of Anaheim High School's Colonists are Western High School's Pioneers.

Concord, California: Concord ( ) is the largest city in Contra Costa County, California.  At the 2010 census, the city had a population of 122,067 making it the 8th largest city in the San Francisco Bay Area.  Founded in 1869 as the community of Todos Santos by Salvio Pacheco, the name was changed to Concord within months.  The city is a major regional suburban East Bay center within the San Francisco Bay Area, and is 29 mi east of San Francisco.

St. Joseph High School (Lakewood, California): Saint Joseph High School is a private Catholic all-girls high school located in Lakewood, California.  It is located in the Roman Catholic Archdiocese of Los Angeles and sponsored by the Sisters of St. Joseph of Carondelet.  Its brother school is St. John Bosco High School

Natalie Romeo: Natalie Romeo (pronounced ROW-MEE-Oh) was born on March 11, 1996, in Walnut Creek, California.  Natalie is an American basketball player at the University of Washington.  She completed her high school education at Carondelet High School, an all girls' school located in Concord, California.

Carondelet High School: Carondelet High School is an all-girls private Catholic high school in Concord, California, United States.  Carondelet High School was founded in 1965 by the Sisters of Saint Joseph.  The school enrolls about 800 students.  It shares some resources with the all-boys De La Salle High School, which is across a side-street that separates them.  De La Salle High School was founded by the Christian Brothers.  Students in their junior and senior years are able to take classes at the other school for four of the school's six class periods, and also as lowerclassmen for language and art.  The school is located within the Diocese of Oakland.

Bishop Montgomery High School: Bishop Montgomery High School (commonly referred to as "BMHS" or simply "Bishop" by students) is a Catholic high school serving twenty-five parishes in the Roman Catholic Archdiocese of Los Angeles.  BMHS was founded in 1957, and staffed by the Sisters of St. Joseph of Carondelet, Conventual Franciscans, and lay faculty.  The 24 acre campus is located in Torrance, California, in southwest Los Angeles County, one mile (1.6 km) from the Pacific Ocean and the Del Amo Mall.  The coeducational student body is approximately 1,200 students in grades 9 through 12, making BMHS the sixth largest private high school in Los Angeles County.  The faculty is headed by Principal Rosemary Libbon.

Acalanes Union High School District: Acalanes Union High School District is a public high school district in southwest/central Contra Costa County in California.  It currently has four schools: Acalanes High School in Lafayette, Campolindo High School in Moraga, Las Lomas High School in Walnut Creek, and Miramonte High School in Orinda.  A fifth campus, Del Valle High School located in Walnut Creek was closed at the end of the 1978-1979 school year and remaining students were transferred to Acalanes, Campolindo, and Las Lomas High Schools.  The district's alternative school, Del Oro High School, opened on the former site of Del Valle High School, closed following the 2009-2010 school year, although the district still operates adult education courses out of that campus.  John Nickerson has served as the district's Superintendent since May, 2011.

Northern Humboldt Union High School District: Northern Humboldt Union High School District is a public school district in Humboldt County, California, United States.  The Northern Humboldt Union High School District operates two four-year high schools, Arcata High School and McKinleyville High School; two small continuation high schools, Pacific Coast High and Tsurai High; one charter school, Six Rivers Charter High School; one community day school, NH Community Day School; and one mental health high school program, Riverbend Education Program.  The school district spans across two of the major cities in Humboldt County.  The superintendent Roger McDonald was appointed on May 29th, 2017.

Supporting paragraphs: Carondelet High School Concord, California
Answer: Contra Costa County